Introduction to

Photography

Author
Abhijit Ray

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Introduction to Photography

Table of Contents
PREFACE.............................................................................................................4

INTRODUCTION ..................................................................................................5
Myths about SLR cameras................................................................................................................. 5
Advantages of SLR cameras over compact cameras ....................................................................... 5
Why should one buy a SLR camera?.............................................................................................. 5
Don’t rush to the store!!! ................................................................................................................... 6
Types of camera................................................................................................................................ 7

SLR Internals ......................................................................................................................................... 8

Basic concepts......................................................................................................................................... 9
Shutter speed .................................................................................................................................. 10
Shutter speed range ..................................................................................................................... 10
Understanding shutter movement................................................................................................. 10
Aperture ......................................................................................................................................... 12
Aperture range ............................................................................................................................ 12
Understanding f values................................................................................................................ 13
Angle of view ................................................................................................................................. 13
Lens Types and effects .................................................................................................................... 14
Film types....................................................................................................................................... 16
Exposure......................................................................................................................................... 17
Combination table ....................................................................................................................... 17
Metering......................................................................................................................................... 18
Exposure Compensation .............................................................................................................. 19
Exposure bracketing.................................................................................................................... 20
Using Flash..................................................................................................................................... 22
Flash techniques.......................................................................................................................... 23
Photo composition .......................................................................................................................... 24
The rule of thirds......................................................................................................................... 24
Using imaginary lines.................................................................................................................. 25
Moving objects in the picture ...................................................................................................... 26
Placing horizon in the photo ........................................................................................................ 26

Digital Photography.............................................................................................................................. 28
CCD ............................................................................................................................................... 29
Pixel count...................................................................................................................................... 29
Resolution ...................................................................................................................................... 30

Sensor size and angle of view................................................................................................................ 30

What to look at while buying a SLR .................................................................................................... 32

Cost.................................................................................................................................................... 32
Body .................................................................................................................................................. 32
Modes ................................................................................................................................................ 32
Metering modes.................................................................................................................................. 32
Flash modes........................................................................................................................................ 33
Miscellanous modes............................................................................................................................ 33

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Introduction to Photography

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Introduction to Photography

Preface
The objective of this book is to introduce the basic aspects of photography to absolute
beginners. Normally everybody goes to buy a camera and then some of them think of
understanding what the camera can do and why the camera does what it does. I have tried to
explain the various aspects of the SLR camera. This document is aimed at informing you about
photography while helping you to decide on your very own photgraphy gear and your journey to
better photographs.
I have added some photos from the web to illustrate all the concepts. These images are
copyright free. I have also drawn some pictures to explain with examples Even though pictures
could not be provided for everything, I have tried to describe every point in a bit of detail. I hope
you can relate the contents in this document with your camera and your photographs. The details
given in this document are sufficient to start a novice off. The document will provide the
foundation of your knowledge, which you can farther later on.
All the best on your new and exciting journey .

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Introduction to Photography

Introduction
To buy a camera we first need to understand a camera. Only then can we make the right
decision. I have had various people coming to me and asking for my advice before buying a
camera. In most cases I have seen that their idea of buying a camera is to go for the most
expensive camera their pocket permits. Yes, this is true. We have to stay within our financial
limits but that does not mean that buying the most expensive possible camera within our limit is
the best choice. We have to know why we are buying the camera, how we are going to use it, for
what. For example, most of us buy a camera to take travel photographs, on social occasions.
This means a relatively cheap camera with 2 inexpensive lenses will suffice. Again there are
people who buy a camera to take good photographs. They require a different camera and
different lenses.
The aim of this document is to give an insight into the various aspects of a camera so
that all of you can make the best possible decision yourselves and after buying the camera you
shall also understand the various features of it.

Myths about SLR cameras

Those who have come to me asking about the benefits of a SLR always ask me keeping
in mind that I ll be giving them the advantages of a SLR over a compact camera. Everyone has
the idea that a compact camera is cheap and very handy, easy to use, aim and shoot whereas an
SLR is complicated and difficult and you have to know a lot about photography to use it, but
that is not completely true.

Advantages of SLR cameras over compact cameras

SLR Camera Compact camera
There is only one lens so whatever you see These cameras have 2 lenses, one for viewing
through the lens is the whole object which is and one for the film. So for close objects you
going to be captured on the film do not get whatever you see, on film
With these cameras you have option of adding With these cameras you have no option of
a lot of accessories that will help and/or adding any accessories. You can only use
enhance your photographic options. Eg, add a whatever is on the camera.
better flash gun, or different lenses, or filters
These cameras are sturdy. Thus their weight is These cameras have flimsy bodies and so they
more. are lightweight. These have to be handled very
carefully.
Can take photographs in all conditions, These cameras can take photographs in fixed
lowlight, extremely bright, rain, haze, cold, hot conditions only. Nowadays, compact cameras
etc. provided the right accessories are present. are more advanced but still they do not come
close to the flexibility of SLR cameras.

Why should one buy a SLR camera?

OK, this question still lingers in your mind. Compact cameras are so easy to carry around
but SLR cameras are heavy, there is a considerable amount of time needed to learn about the
cameras, you have to waste a lot of film to take a considerable good photograph. Right?
WRONG!!!!! Amazingly enough, today the SLR cameras can be used just like a compact

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Introduction to Photography

camera, i.e. like a point and shoot camera but with better image quality and still have all the
flexibilities and advantages that a compact camera has. The main problem with compact cameras
is that it decides what you can do and not the other way round.
But what about cost? SLR cameras cost way too much. Compact cameras are less
expensive and very affordable. TRUE. Let s look at a live example. The lowest price of a SLR
camera in 2001 was 180 and a somewhat ok compact camera was about 100. But judging the
benefits of both I would say it is better to go for the SLR as buying a camera is a one-time
investment. So if our pocket permits it is better to spend a little better and get something which
will be a pleasure throughout our lifetime rather than save some money now and moan about
losing some shots.
So have we decided on a SLR yet? Yes? Ok, now let s see how to go about choosing the
right camera that suits not only our budget but also our passion for photography. First let us see
how many types of cameras exist on this planet.

Don t rush to the store!!!

Have you gone through some photography magazines? Could you understand all those
figures about photos? Do you understand when a particular picture is referred to as Taken at 60
and f/5.6 ? If your answer is no. read on .
Let us understand a few points about photography so that you can understand the jargon
the salesmen at the store say and once you ve bought your own machine you ll be able to shoot
confidently from day one.

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Types of camera
There are various kinds of camera.

TLR ( Twin Lens Reflex) SLR (Single Lens Reflex)

Rangefinder Compact

TLR cameras and Rangefinders are nearly extinct nowadays. So I will not go into the
details of those kinds of camera. Here I shall stick to SLRs only and sometimes I shall pick up
references from compact cameras, as these are very popular now.

OK, SLR stands for Single Lens Reflex. Why Single and what Reflex? Yeah, I know
you re thinking about that already. I ll come to that a little later. These are generally 135 film
cameras (those cameras which almost everybody has). There are other SLR cameras that use
120 films. .

Note: 120 or 135 are just a number for denoting different sizes of films

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SLR Internals
Let s look at the cross section of a SLR camera. Below, the path of a light ray is shown.
This is the condition when we look
through the lens for viewing only and not
while the photograph is being taken.
When the photograph is taken then the
mirror goes up and meets the bottom of Pentaprism
the pentaprism and light ray falls directly Eye
onto the film thus creating the image. At

Shutter plane
this point of time the photographer is
unable to view the subject because the
light rays no longer reach the eye of the Path of a light ray
photographer. Once the photograph is

Film plane
taken the mirror comes back to its
original position. Thus the camera is
called a reflex camera and since the
camera has one lens the name becomes
Single Lens Reflex. Another thing Mirror
happens when the photograph is taken. Lens
There is a shutter in front of the film
plane. The shutter opens and the light falls on the film, creating a latent image on the film. This
image formed is called latent because until the image cannot be seen until the film is developed.

What is a latent image?

A latent image is the image formed on the film once light falls on it. It is
called latent because the image is not viewable until it is developed in a lab.

The following images illustrate the SLR functionality with different pictures.

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Basic concepts

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Shutter speed

Question. What is shutter speed? OK, imagine you are in a completely dark and closed
room. There is a window that can be opened only for a moment. To see the outside world this
window has to be opened. Once this window is opened the view is seen for a moment. So even if
there is a car moving at top speed outside the car will seem to be static as this window opens just
for a moment. This is exactly what shutter speed is.
The SLR is the dark and closed room and the window is the shutter. The shutter
in a camera opens and closes according to the speed which the photographer sets. Once the
shutter opens, light falls on the film and the latent image is formed. Now the shutter can remain
open for say 1/60th of 1 sec or 1/125th of 1 sec. This is called shutter speed. If the duration is
1/60th of 1 sec then it is referred to as 60. So shutter speed is the reciprocal of the duration of the
open shutter.
This is not so important to you as a photographer. What is important to you is the
implication of the whole thing and all the things that it affects. Any camera produced in the
world will have a range of shutter speed like this,

Shutter speed range

1000
Decreasing shutter 500
speed implying increase 125 Shutter speed with
in light falling on the film, 60 duration less than 1 sec
i.e. shutter speed of 60 30
allows double the light 15
allowed by shutter 8
speed of 125 and half 4
2 Shutter speed with
the light allowed by 30
1 duration more than 1 sec
2
4
Shutter speed increases or decreases a factor of 2. It means that changing the speed
from 30 to 60 means higher speed. It also means that the duration increases from 1/30 sec to
1/60 sec. Similarly changing the speed from 30 to 15 means lower speed, change from 1/30 sec
to 1/15 sec, which means higher duration. In terms of photography we refer to as higher or lower
speed and not duration. This change of one step higher or lower is also called changing one stop
(higher/lower) in photography jargon.
We see that one stop change increases or decreases the shutter speed by a
factor of 2 and so the light that enters the camera is also halved or doubled. In the previous
example changing shutter speed from 30 to 60 increases speed by 2 and so light falling on the
film is halved. On the other hand change from 30 to 15 allows double the amount of light to enter.
So this shows how the amount of light can be manipulated just by changing the shutter
speed. Thus light can be changed 4 times by a change of 2 stops ( 2 X 2 ), 8 times by 3 stops ( 2
X 2 X 2 ) and so on.

Understanding shutter movement

The shutter is made up of 2 shutter curtains, one in
front of the other. If we open the back of the camera
Before taking the then this is what we ll see. Suppose now, we ll open
shot. (both shutters the back of our camera(which does not have any film
together)
loaded) and fire a test shot. Then we ll only get to see
Fig. A one shutter curtain, i.e. the one that faces the film
(Shutter1) and not the one that faces the lens

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(Shutter2). Fig A shows this very condition. Here we

are assuming the names of the shutter curtains for our
Shutter 1 understanding.
Once the shutter is pressed Shutter1 starts moving up
Shutter 2 but Shutter2 remains static (fig. B). Only after a certain
amount of time does Shutter2 start moving up. So a
Fig. B thin slit is formed between the shutter curtains. This slit
of light allows light on to the film and thus the latent
image is formed on the film. It is as if light from the
scene is sprayed all over the film. After the photograph
is taken Shutter2 comes in front of the film.
Light slit On autofocus cameras, the film is then wound and the
next frame comes into position and Shutter1 and 2 go
back to their original position. On manual cameras this
Fig. C is done manually when the film-winding lever moves
the film to the next frame.

Why have this kind of mechanism?

Shot complete. (Again This mechanism is very useful because with just
both shutters one curtain it would have been impossible to have fast
together but in shutter speeds.
reverse order) We know that in SLR s the shutter guards the
film from light when we see through the lens.
Fig. D Suppose the camera had only one shutter then
the shutter has to open first and then close the frame.
Now if we take a photograph at shutter speed 500 then the shutter had to move twice.
That means the shutter had to move at a speed of 1/1000th of a second. This would mean more
wear and tear of the curtain gears. With the 2-curtain mechanism there would be no need for that
kind of movement. The speed of the curtain would be the set shutter speed.
When we use a lower shutter speed, Shutter2 starts after Shutter1 has moved up for
quite some time and for a higher shutter speed it is just the opposite. Hence for a higher shutter
speed the slit is smaller in width and vice versa for slower shutter speed.
If we start from the top shutter speed and keep on coming down, there will be
one value for which Shutter2 will start after Shutter1 has moved up, leaving the frame completely
open. This shutter speed is called the Flash Synchronisation Speed

Flash synchronization speed

This is the maximum shutter speed that should be used
during flash photography. This is different for different cameras. It
is generally 60/90/125. If a camera has synch speed of 90 then
photos with the flash should be taken with a shutter speed of 90 or
less than that. On some advanced autofocus cameras combined
with dedicated flashguns, there is no flash synchronization speed.
This will be discussed in detail when we discuss flash photography.

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Aperture

Now this is not directly related to your camera. Actually, this is a feature of the lens. Just
like shutter speed, aperture also has a range of values. A typical range of values looks like

Aperture range
45
32 Only on specialised lenses
Decrease in f value or 22
increase in aperture 16
implying increase in light Available on all types of
11
falling on the film, i.e.
lenses, zoom or fixed focal
8
aperture 5.6 or f/5.6 5.6
length lenses
allows half the light 4
allowed by aperture 4 or 2.8
2 Available only on Normal lenses, very
f/4
1.8 expensive/ specialised zoom lenses and
1.4 fixed focal length lenses
1.2
1
Aperture is denoted as f. An aperture of 5.6 is denoted as f/5.6. Aperture is in plain
English is a hole. In photographic terms it does go to mean just that but it is simplified to an extent
so that it can be related to light. So from common sense we get that a larger aperture means
more light coming in. But it seems paradoxical here as a higher value allows less light (see chart
above). What does this mean and how does this come about?
Let s see what the aperture looks like. When you take the lens off the camera or you open the
camera back you ll see something like this

The outer shell of the lens (the

plastic/metal part). This is the part
which holds the lens elements in place

The back of the lens (glass)

We shall look at the lens back because that s where the aperture comes into play.
From the picture in the left we can see how the aperture
is made. There is a group of curved blades (in the picture
the blades are shown as straight edged) which rotate to
create the required aperture set by rotating the aperture
ring on the lens or from the camera. The aperture rings
are generally found on manual focus lenses. In autofocus
cameras the aperture is controlled from the camera itself
although it is a feature of the lens. All lenses have a
minimum and a maximum aperture. The minimum
aperture determines the maximum amount of light that
can enter the camera. Sometimes the aperture is also
Aperture made by denoted as 1:4 or 1:5.6 instead of just f/4 or f/5.6. Why is
the blades that? It is because the aperture is also a ratio of the
ambient light with the light entering the camera. Thus an
Aperture blades aperture of 4 or f/4 also means that only 1/4 of the
th

ambient light is falling on the film.

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Understanding f values
Each aperture setting, say f/8 is called One Stop in photographic terms (just like shutter
speed). What we have to know is that a change of aperture from one stop to another stop, i.e.
change in one stop, will reduce/increase the light by a factor of 2. Hence a change from f/5.6 to
f/4 will give u double the light whereas changing from f/5.6 to f/8 will giev you half the light at f/5.6.
Here we are assuming that shutter speed is kept constant throughout.
Let us look at why we have such odd values to represent the aperture values. Why do we
have f/16, f/11? For understanding this we shall take a few pages out of our school math s book.
At maximum aperture the aperture blades do not guard any part of the lens. Then the area of the
2
lens is, π r , considering that the radius of the aperture is . Now the aperture is changed by 1
stop. So the light will be halved. For letting in half the light that was entering previously the area of
2
the aperture will be halved. If the radius is now R, then the area will be π R . So we know that,
π × r2 2 r
= ⇒ = 2 = 1.41 Hence we see that the ratio of the radii is of the order of
π ×R 2
1 R
1.41. So with a reducing aperture the radius decreases by 1.41 times. The f-number is the
number of times the radius has decreased (number of f-stops on the lens) multiplied with the
minimum aperture and 2 . So if the minimum aperture of a lens is 2.8 and the number of f-stops
is 6 then the aperture range is 2.8, 4, 5.6, 8, 11, 16.

Angle of view
In photography, angle of view describes the angular extent of a given scene that is imaged by
a camera. It parallels, and may be used interchangeably with, the more general visual term field
of view.

The angle of view of a camera is a function of three parameters:

• The dimensions of the film format or image sensor;

• The focal length of the photographic lens projecting the image; and
• The kind and degree of distortion of the lens.

The angle of view for a 50mm lens with 35mm film has an angle of view of ~ 43°

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Lens Types and effects

Lens is the most important part of the camera. The lens decides what parameters are needed
for the exposure and hence all aspects of the photograph.

Lenses are often referred to by terms that express their angle of view:

Ultra wide-angle lenses, also known as fisheye lenses, cover up to 180° (or even wider in
special cases)
• Wide-angle lenses generally cover between 100° and 60°
• Normal, or Standard lenses generally cover between 50° and 25°
• Telephoto lenses generally cover between 15° and 10°
• Super Telephoto lenses generally cover between 8° through less than 1°

Zoom lenses are a special types of lenses wherein the focal length, and hence angle of view,
of the lens can be altered mechanically without removing the lens from the camera.

Longer lenses magnify the subject more, apparently compressing distance and (when
focused on the foreground) blurring the background because of their shallower depth of field.
Wider lenses tend to magnify distance between objects while allowing greater depth of field.

Another result of using a wide angle lens is a greater apparent perspective distortion when
the camera is not aligned perpendicularly to the subject: parallel lines converge at the same rate
as with a normal lens, but converge more due to
the wider total field. For example, buildings appear
to be falling backwards much more severely when
the camera is pointed upward from ground level
than they would if photographed with a normal lens
at the same distance from the subject, because
more of the subject building is visible in the wide-
angle shot.

Because different lenses generally require a

different camera subject distance to preserve the
size of a subject, changing the angle of view can
indirectly distort perspective, changing the apparent
relative size of the subject and foreground.

What is a Normal Lens?

A normal lens is a lens which has an angle of view equal to the angle of
vision of the human eye. For cameras which use 135 film the normal
lens is 50mm. This value depends on the film that is used by a camera.
Why? Because the formula is,
2 2
Focal length of a normal lens = √ (length of film + breadth of film )
Since the viewable area on film (negative size) is 24 X 36 mm, the
length becomes 43.5mm. This is taken to be 50mm. Actually a range of
focal length is taken for normal lens. 45-55mm lenses are taken to be
normal. Any focal length below 35mm is wide angle and above 80mm is
telephoto. Any lens which has variable focal length is called a zoom lens.
A COMMON MISCONCEPTION PEOPLE HAVE IS THAT ZOOM LENSES ARE
TELEPHOTO LENSES AS THESE LENSES ARE IN THE TELEPHOTO RANGE.
ZOOM LENSES NEED NOT BE TELEPHOTO LENSES. There can be wide-
angle zoom lenses, e.g. 19mm 35mm.

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Below: An example of how lens choice affects angle of view. The photos below were taken by a
35 mm camera at a constant distance from the subject. Notice how the angle of view changes
with change in focal length of the lens and depth of field (see page 18) decreases with increase in
focal length.

Figure i - 28 mm lens Figure ii - 50 mm lens

Figure iii - 70 mm lens Figure iv - 210 mm lens

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Film types

Film consists of a thin Silver Bromide coating on a strong base of gelatin (colourless).
The gelatine has no function other than holding the silver bromide coating. Silver bromide is
sensitive to light. So when light falls on the film the compound breaks into silver and bromine. The
silver is deposited on the film base and the bromine is released as gas. Thus the latent image is
formed. A picture consists of light and dark parts of varying intensity. The parts where bright light
falls cause rigorous reaction on the frame and so more silver is deposited and those parts of the
frame, which do not receive any light, does not deposit any silver. So you see that the whole
reaction depends on the intensity of light. So parts where reaction takes place also can also have
some unreacted silver bromide left. Once the film is developed in a lab the unreacted silver
bromide is washed off and only the silver remains on the film base. Thus the negative is made.
This is the scenario for Black&White film. For Colour
Silver bromide coating film there are 3 layers of silver deposit. One layer for
Film base receiving the colour red, one for blue and one for
green. Any colour is a combination of these 3 colours.
So cyan light will deposit silver in both blue and yellow
because it is a combination of both these colours.
Blue layer
Green layer What is a frame?
A frame is a picture on the roll of film.
Red layer When we refer to each picture on a negative we
are actually referring to each frame on the
Film base
negative.

So the first category of film is whether it is Black&White (B&W) or Colour. There is a

subcategory within this. That is the film speed. Film speed is denoted as ASA, ISO and DIN.
ASA → American Standards Association ISO → International Standard organization
DIN is some German standard, but the full form is unknown to me. This is now obsolete. ASA and
ISO have the same values.
Film speed ranges from ISO(or ASA) 25 to ISO 6000. Generally we get ISO 100, 200 and
400 in the shops. What do these values convey? ISO/ASA values give you an idea about how
sensitive the film is to light. Higher the value, more sensitive is the film. The sensitivity of the
films is relative. No absolute value is ever used. For example, an ISO 200 film is twice as
sensitive as a ISO 100 film and half as sensitive to light as ISO 400 film. That means if we use a
film with high ISO value, it would require less amount of light. What it means to a photographer is
that he can use a higher shutter speed and/or lower aperture (higher f value) than what he would
have used if he had used a lower ISO film. This is shown in the chart below, Combination table
So it seems that using a film with higher ISO value is always better as it allows us to use
a larger range of shutter speed and aperture in general light. True, but it also has a disadvantage.
Faster films (films with high ISO values) tend to have larger grain, especially in B&W films. What
is grain? If you look closely at pictures on old newspapers then you ll see that the pictures are
actually created by groups of dots. These are generally not visible except in large sized prints
(photos) and the film used was fast, i.e., ISO 400 or more.
Note: There are other categories also. B&W films can be panchromatic or
orthochromatic. Colour films can be compensated for daylight or for tugnsten
light. The films that we normally use are daylight compensated.

So you must think carefully before selecting your film. Think of where you are going to shoot.
Think of the light condition at your shooting area, if you have a tripod or not, if you are going to
make large prints, if you actually want grains on your shots or not (sometimes photographers
prefer grains on their prints for special effects).

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Exposure

Each photograph is taken by a combination of shutter speed and aperture. Film speed is
constant for a particular film. So once that film is loaded the speed is set automatically by
autofocus SLRs (though it can be changed manually) and set manually for manual SLRs.
Aperture and shutter speed has to be set together to get a photograph. One cannot go
without the other. The combination of shutter speed and aperture allow a certain amount of light
which is always constant for that combination. This is called exposure. Suppose we use f/5.6 at
60. This will allow the same amount of light for every camera, lens or anything that you change.
Now suppose that a particular photograph was taken with f/5.6 and 60 then we could achieve the
same result by changing shutter speed to 30 (this allows double the light than 60, Refer to Shutter
speed range) and f/8 (this allows half the light than f/5.6, Refer to Aperture range). Thus the same
amount of light is allowed as in the previous case.
So, if a photo was taken at f5.6 and shutter speed of 60 with ISO 200 film, then it can be
taken at f/8, shutter speed 60 with ISO 400 film. This is the most important aspect of
photography. Check the table below to see how all the parameters can be interchanged to
give you the same photo.
Row 1 shows the original configuration.
Row 2 to 5 shows how the same photo
Combination table
can be taken by varying shutter speed
Serial Shutter Aperture ISO and aperture for ISO 200. Row 6,7 is
speed the configuration for the same picture
1 60 5.6 200 using ISO 100 film (once shutter speed
2 30 8 200 is changed and once aperture). The
3 125 4 200 same thing is shown in Row 8,9 with
4 500 2.8 200 ISO 400 film.
5 15 11 200 From the chart we can conclude that if
6 60 4 100
aperture is increased by n stops then
7 30 5.6 100
shutter speed has to decreased by n
8 125 5.6 400
stops to get the original picture and
9 60 8 400
vice versa.
Here we get a clear picture about the relationship between shutter speed and aperture for
a fixed film speed. Film speed is never changed because it is constant for a particular film. The
values are given in the chart for giving you an idea of what the shutter speed and aperture will be
for different film speed. We should choose the film that we need accordingly.
Why should we vary shutter speed and aperture once we have a particular
combination? The camera makes a suggestion about the shutter speed and the aperture, refer
to Metering chapter. This value might have to be changed for our needs. For instance For
capturing a fast moving object we need a high shutter speed and a low aperture. Once we get the
suggestion from the camera then we ll know just how much to change. For example when the
camera suggests f/11 at 250 on a bright day. If we need to capture the photo of a fast moving car
we need a shutter speed of 500, say. Then we ll change the setting to f/8 at 500. We refer to the
suggestion made and we see that the required shutter speed is one stop more and hence the
required aperture would be 1 stop less.

Never change the film speed when the film is loaded. Only set the
speed when the film is loaded if the camera does not set the film speed
automatically. Cameras set this automatically by the DX coding on the
film canister when the film is placed inside.
If the film speed is changed then you will get consistent underexposed or
overexposed pictures depending upon the change.

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Metering

Every camera has an inbuilt meter to measure light and accurately decide which
combination of shutter speed and aperture is to be used in any condition. The autofocus cameras
make their decision based on the mode set by the photographers. Almost all autofocus cameras
have 4 modes P, S, A, M.
P Program mode
The modes are explained in detail later in the book.
S Shutter priority mode
Refer to Modes
A Aperture priority mode
M Manual mode
Manual cameras have no modes built in. When we look through the camera and half
press the shutter, we get all kinds of information (depending on the camera), like shutter speed
and aperture. The camera based on its light meter gives these values. When you press the
shutter release button the camera will take the photograph with the shutter speed and aperture
displayed in the viewfinder. Since we get the values when we look through the camera, this kind
of metering is called TTL metering. TTL stands for Through The Lens. There is another kind of
metering called Off Camera metering. This is done by specialized meters, which are bought
separately. We shall not deal with those in this book. Instead we shall look closely at TTL
metering which is found all cameras.
TTL metering is of 3 types.
Centre weighted
• Centre weighted metering area
When you look through the viewfinder you will see
something like in fig. A. It means that the meter will give
30% weightage to the area within the larger circle and
70% weightage to the area of the rectangle outside the
large circle. This 30-70 ratio is not fixed and varies from
camera to camera. It can be 25-75, 35-65 or even 40-60.
This kind of metering is found even in the old cameras.
This metering is useful for general photographs where Fig. A
the subject is in the centre or the subject is covering a
large part of the frame.

• Spotmetering
Spot metering is not used in general photography. It is
used only in special conditions. When Spot Metering is
being used, the small inner circle in the viewfinder is the
only sensitive part. The camera gives 95% weightage to Spot metering zone
this area and only 5% weightage to the rest of the view
finder. It is very useful in conditions where there is a very
large variation of light throughout the frame whereas the
subject maybe quite small or a part of the subject has to
be correctly exposed. In such a case spot metering is
used. Through the view finder the small circle has to be
Fig. B
placed on the subject or the part of the subject, which
has to be correctly exposed, and then the shutter should
be half clicked to activate the meter.
Spot meter is less sensitive to light than centre weighted meter. There maybe cases
where spot meter is unable to give you a exposure due to bad light but centre weighted
meter can.
All cameras do not have a spot meter. Medium range to upper range cameras have this
kind of metering.

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Important note: Film as well as digital camera CCD cannot take too much
variation in light. If a scene has a large variation of light, from very dark to
very light, films cannot record every part of the scene perfectly exposed.
For instance, a scene where bright daylight and shadow will not show both
light and shade properly illuminated. Either shadow has to be properly
illuminated with the lighted parts very bright or the lighted parts properly
illuminated and shadow parts quite dark. It has to be decided by the
photographer and the meter has to be focused on that part of the scene for
the correct exposure.

• Evaluative metering
This kind of metering is present only in autofocus
cameras. The frame is divided into multiple regions Metering zones
which vary from camera to camera. The camera gives a
weightage to each zone and calculates the shutter
speed and aperture accordingly. Different manufacturers
name this light meter in various ways. Nikon uses 3D
Matrix metering, CANON uses Evaluative metering,
Minolta uses Honeycomb pattern metering. All these are
customized forms of evaluative metering. Fig. C
The only difference with the previous meters is that you will not be able to see the
different zones through your viewfinder as in the case of spot meter or centre-weighted
meter. This meter is good for almost all kinds of scenes.

Exposure Compensation
Although the TTL meters are very advanced, they fail in certain conditions, in conditions
where there is too much light and where there is very little light. In both cases, cases the meters
fail to give proper exposure.
What do you do in such cases? Yeah, we all depend on the meter to give us the
correct exposure but if it fails then we ll end up with very bad photo(s). First of all, how do we
know if the meter is failing? OK, here s how. Check if the subject is backlit, i.e. if the light source
is behind the subject. Now light source does not necessarily mean that the light is directly behind
the subject. If we want to take somebody s photo in the shade with the sky as the background,
the sky becomes brighter than your subject. Hence he/she is backlit. So in this case the camera
will look at the whole scene and decide that there is a lot of light around and so it will be fooled
into suggesting a lower exposure. The result? In the photo you will have a beautiful sky and a
very dark, almost unrecognizable, person. Since there was so much light the camera was fooled
into underexposing the subject, as the subject does not cover a very large area of the frame.
Now how do you avoid this? First aim your camera at the sky and take its exposure
reading. Then come close to your subject so that only he/she covers your frame. Take that
exposure. Suppose, the exposure of the sky is f/11 at 500 and your subject is f/5.6 at 125. You
see there is huge variation of 4 stops.
One way is to set your camera to use only the subjects exposure, by manually changing
in manual mode or by using the camera s feature of exposure lock (this feature may not be
present in all cameras. It primarily locks the exposure taken at a particular point and does not
change even if the scene changes). Another way to do this is to compensate exposure. In such a
case (where the difference is 4 stops) compensate for +2 stops. This way you will get a much
better picture of your subject. Setting the camera to compensate is specific for a camera, so it is
better to go through the camera manual.
± n stops of compensation is also referred to as ± n EV. EV → Exposure Value

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Similarly, in a dark condition where most of the frame is is dark and you have a well
lighted but relatively small subject, compensate by a negative value as the camera will tend to
overexpose the photo.

Exposure bracketing
As in the previous example I had explained how the camera can be fooled and how you
decide to compensate for exposure. Now there is a very simple catch to it. Supposing that the
photo that you are going to take is of great value to you. It might happen that the picture that you
are going to take is a once in a lifetime chance photo. In such a case what do we normally do?
We take the same photo with +1EV, -1 EV and at normal exposure. That means taking 3 photos,
one with 1 stop overexposure, one with 1 stop underexposure and one with the exposure
suggested by the camera. So what happens is that if the camera had originally suggested an
exposure that may be say, -1 EV of the perfect photograph, you will be capturing it by covering a
wide range of exposure. This is called exposure bracketing.
Or if you want to be very particular, you can take 5 photographs, ± 2 stops. In some
cameras this is an inbuilt feature. In those cameras only the EV has to be set and fired away. In
cameras, which do not have this feature, the photographer has to manually change the exposure.
If you are going to do this manually then changing shutter speed and/or aperture can vary the
exposure. You have to decide on that.

Change shutter speed or aperture?

Like we said before we can either change shutter speed and/or aperture. Now how do
we decide which one to change? Here are a few guidelines to help you out.

• Depth of field (DOF)

This something which could have been explained with just 2 photographs. Well, since I
have to tell you everything in black and white, here goes. When you focus on an object through
the lens, you are basically moving the lens up and down so that the image of the subject falls
onto the film. So what you are doing while focusing, is that the lens moves a particular distance
according to the distance of the subject from the camera.
In turn, the subject is focused on the film plane. Now what happens is that when the
photo is taken, then some amount if distance in front of the subject as wells as some distance
behind the subject is focused. Camera
In the figure Y is the distance of between the Distance of
camera and the first object in focus and Z is the distance subject from
of the last object in focus. The difference of Z and Y is camera
the Depth of field (DOF). ∴Depth of field = Z Y Subject
DOF depends on the distance of the subject Y
from the camera, the aperture and the focal length of the Z
lens. For a larger a DOF we go for a smaller aperture.
DOF decreases with decrease in subject distance from
the camera and decreases with increase in focal length. Depth of field
For taking photographs of scenery we take shots at low aperture (f/11 or f/16) so that we
get a very large DOF. For taking shots of scenery, the object is at infinity (with respect to the
lens). For every lens there is a maximum distance upto which it needs focusing. After that point
everything will be focused but the lens only needs to be set at infinity. Eg. A lens focuses upto a
distance of 10m. For any subject beyond 10m the lens will be set at infinity.
DOF is inversely proportional to focal length of a lens. That means a lens with higher
focal length will have a smaller DOF than a lens with a smaller DOF. Eg. DOF for 50mm lens is
greater than DOF with 105mm lens when the same photograph is taken at the same aperture.
That is why landscapes are taken with wide angle lens whereas portraits are taken with a a
telephoto lens.

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Note: Using a very big aperture very close to the subject can give such a
small depth of field that the subject s nose is focused whereas the ears are
out of focus. This is sometimes wanted and sometimes not. When in doubt,
use exposure bracketing or use DOF preview button if the camera has one.

While taking portrait photos we want a lower DOF so that disturbing elements behind the
subject is off focus. At such a time we use the maximum aperture of the lens. That gives us the
minimum DOF.

Examples of depth of field

Picture shot with f/32. The background is sharp and crisp. Picture shot with f/5.6. The background is blurred.

• Capturing a moving object

There are times when you want to photograph a moving car, a flying bird, or for that
matter any moving object. The light conditions maybe good and so the camera might suggest a
shutter speed of 250 at f/16. But this might not be enough for the subject. So you change it to
1000 at f/8. This is a case when the shutter speed needs to be changed.
For a moving object the shutter speed
has to be changed depending upon the relative Object
speed of the object. For a moving object which
needs a shutter speed of 250 at a distance of
say, 10m from the subject, will need a much
higher shutter speed when the distance between A
the camera and the object is less than 10m. This
is because the relative speed increases with B
decrease in distance.
Suppose we have an object moving along the arrow. We have 2 cameras, A and B,
placed. Since A is closer to the line of movement of the object, the relative speed of the object will
be more than B. Hence camera B will need a higher shutter speed than A.

• Minimum handheld shutter speed

The minimum shutter speed for handheld photography is 60. If the camera gives a
shutter speed of less than 60 then try changing the exposure so that the minimum shutter speed
is at least 60. If you cannot then you should use a tripod.
This value of 60 is used because it is seen that most photographers can hold the camera
steady at 60 and above. Below 60 there can be very minimal shake while the photograph is being
taken. This may not show up on a small postcard size photograph, but will show up in a slightly
bigger photo, 5 X 7 and bigger.
As you have more and more experience and expertise, you will be able to take
photographs with lesser shutter speed like, 30, 15 or even 8. But that will only come after quite a
bit of expertise.

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Using Flash

Flash is a device that is used for providing light in those conditions where the ambient
light is inadequate. A lot of autofocus SLR s come with built in flashes. No manula cameras have
built in flashes. But all cameras have a provision to attach an external flash on the camera. The
point where the flash is connected on the camera is called a hot shoe.
Flashlight is equivalent to sunlight. No no. I don t mean that at night you should have
photos, which look like those were shot during daytime. What I mean is that the colour of light
emited by a flash is the same as sunlight. On the colour temperature chart ( this chart lists the
temperature for all kinds of light) the light for sunlight is 6600 K (Kelvin). Flashlight has the same
colour temperature. That is why when flash is used during the day, the light from the flash and
sunlight mix very well. Hence using a flash during the day is a very good way of lighting the
shadow areas.
How do we rate a Flashgun? A flashgun is rated by the value of GUIDE NUMBER
(GN). It tells us how powerful a flashgun is. Guide number (GN) = Aperture X distance of subject.
We know that the intensity of light decreases with increase in subject distance from the camera.
So as the aperture is increased it allows more and more light on to the film. So now we know that
when the distance increases then the aperture also has to increase. GN also has to be defined
whether the value is in feet or in metres. For example, GN of a flash is expressed like this, 24 in
metres at ISO 100. The equivalent GN of the flash in feet will be 78.74 in feet at ISO 100, as 1 m
= 3.28 feet.
Now suppose we are using a flash which has a guide number of 14 in metres at ISO 100.
Now the distance of the subject from the camera is 2 m. At this distance, the aperture will be
GN/distance, i.e. 14/2 = 7. We generally do not have a setting of f/7 as aperture. So, the next
closest value will be f/8. So the aperture will be set to this. The film speed is also important. If the
film in use is ISO 200, then the aperture will be halved. Here half the aperture means 7 X 2 = f/14.
So the closest shutter speed will be f/16. Hence this aperture should be used. Thus we see that
for more sensitive film the aperture reduces and so the depth of field increases.
Flashlight is visible upto the distance permissible by the largest aperture on the
lens. If the lens has f/4 as the largest aperture and the GN of the lens is 24 in metres at ISO 100
then, if you re using ISO 100 film, then the maximum distance that the flashgun will cover is 24/4
= 6m. If you re using ISO 200 film then the distance will be doubled. That is, 12m. So at ISO 200,
the maximum distance that will be visible on film is 12m. I have seen people using flash for taking
photographs of objects very far off, nearly 100m with tiny flashguns. This will never work because
the flash does have enough power to illuminate something that far off.

Note: Never set the shutter speed above the flash synchronization speed
when using a flash.

In autofocus cameras, the shutter speed is normally set by the camera itself and so it
never goes below the flash synchronisation speed. But, if you are using a manual SLR or an
autofocus camera in Shutter priority mode or in Manual mode then the shutter speed depends
upon you. As discussed in the Shutter speed, we have seen that there is a maximum shutter
speed for which the frame is completely open. Now what happens in flash photography is that the
flash is light source that is triggered once the shutter release button is pressed. The flash emits
light for only 1/16000th of a second. Now the shutter speed is . This light source can fire at
anytime starting from 0 to 1/x seconds. So what we need is an open window to absorb all the light
on the film. If the shutter speed is more than the synch speed then the frame is never completely
open and so the shutter curtain will block the light coming on to the film. There are times when
the photographer had forgotten to set the shutter speed on or below the synch speed and have
got a picture that is half lighted.

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Flash techniques
There are quite a few techniques with flashguns. I do not intend to go through all of them
but I will discuss one or two basic techniques here.

• Fill flash
A very basic mistake or thought that people have about flashguns is that they think
flashguns can be used only when it is dark. It is not so. Flash can and should be used in broad
daylight. Yes, on a very sunny afternoon, if you take photographs of people then you shall get
ugly shadows on the eyes and nose of the subject. This can be avoided by using the flash. On
autofocus cameras, the exposure is set automatically so that the flash light as well as the sunlight
mixes together as both sunlight and flash light have the same light temperature.

• Bounce flash
Sometimes, while shooting indoors with a flash we do not prefer the flashgun to fire
directly at the subject. Instead, if the flash head is tilted upwardsand fired (provided there is a
ceiling and the flash has a tiltable head) then the light is reflected from the ceiling on to the
subject. The advantage in this case is that the surrounding area of the subject is also equally
lighted and it gives a smooth effect. Remember to overexpose the photo by 1.5 stops at least, as
the ceiling will absorb a lot of light and the light has to travel up towards the ceiling and then down
to the subject. Also check that the ceiling is white coloured. If the ceiling is of a different colour,
the subject will be illuminated by that light of the colour of the ceiling

• Slow Flash synch

This is a technique that is used mainly to get the ambient effect alongwith the flash effect.
Suppose, in the evening, a man is standing in a park and behind him there are beautifully
illuminated buildings. Normally, the man will be well lighted but his surroundings will be absolutely
dark or faintly visible. This is because the background is far off and so the flashlight will not reach
the buildings. To get the subject as well as the background what we should do is take the
photograph with the flash and also reduce the shutter speed. First take the reading of the
background with the aperture set to what it should be after calculating from the subject distance
and the GN. With that aperture and shutter speed take the photograph of the subject. Slow and
night photography is a big field. This was just an introduction into this aspect of photography.

There is a group of flashguns called dedicated flashguns. These flashguns can give a
properly lighted photo with any shutter speed. Actually dedicated flashguns can work with certain
cameras. For instance CANON manufactures dedicated flashguns only for CANON cameras,
Nikon, Minolta and a whole lot of other manufacturers do the same for their products. What
happens with these flashguns is that once the shutter release button is pressed the flash starts
firing for sometime. So there is no need of setting the shutter speed to the synch speed or below.
These flashguns have other features like flash autozoom. Actually these flashguns communicate
with the camera and so when the lens zooms the flash head also zooms.
Flashes also have an angle of light spread. Just like lenses have a viewable angle,
flashes have a similar angle. So while zooming the flash head manually remember that the angle
of light is equal or more than the lens angle of view. For all flashguns with zooming heads there is
a scale on the head, which shows the angle of light equated to the lens focal length. This value is
given in mm, i.e. equivalent to the lens focal length. Set this value equal to the focal length of the
lens in use. Suppose if the flash head is set to 35mm and the focal length of the lens is 28mm
then the edges of the photo will appear dark.

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Photo composition

Composition is the key to a good photograph as is exposure. Exposure determines how

well the photo is illuminated (what has been highlighted and what has been kept in the dark) and
composition determines how the image is defined within the boundaries of the photograph. There
are some simple guidelines but these are not hard and fast rules. Following these guidelines will
help you take most of the pictures but do remember that some highly acclaimed pictures have
violated these as well. In summary, it is suggested that one follows these thumb rules before one
starts to ignore them.
Most people take a picture by placing the subject of the photo right in the centre of the
photograph. This may suffice in some cases but the photo can be made more aesthetic if certain
aspects can be kept in mind while taking the picture.

The rule of thirds

This is a very common guide for better photographs and it is used in most photographs.
The rule of thirds says that if you divide the picture area by 3, horizontally and vertically, then
the intersection points within the picture area are the strongest
areas in the picture and the subject should be placed there.
Now, you would have 4 such points in the photograph where
you should place your subjects.
The image on the right shows the shows the divisions
horizontally and vertically. It also shows the 4 intersection
points.
You might have 1 subject in a picture. In that case out
of the 4 intersection points where are you going to place the
subject? There are other factors which you need to consider
before you click the shutter. You will get the answer to this question shortly.

Take a look at the following pictures.

Notice how the seagull has been placed in the

picture. It would have been a dull picture if the seagull
was placed in the centre. The shadow and tracks of
the seagull would have been missed.

Another example. The lighthouse is placed on

the top right intersection of the rule of thirds. The
hillside, the V shape, adds to the picture.

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Using imaginary lines

Using imaginary lines can make very powerful statements in a photo. Anything within the
picture representing a line has an effect of drawing the eyes of the viewer into the photograph or
out of the photograph. It is up to the photographer to decide how he/she wants the viewer to feel
while looking at the photo.
Select a camera angle where the natural lines of the scene lead the viewers' eyes into
the picture and toward your main center of interest. You can find such a line in a road, a fence,
even a shadow. Diagonal lines are dynamic; curved lines are flowing and graceful. You can
often find the right line by moving around and choosing an appropriate angle.

Note: Diagonal/Curved lines within a picture are more pleasing to the eye than
direct lines coming into the photo from the middle of a frame.

The picture shows the use of rule of thirds as well as

lines.

It is best to give a feeling of the path of the subject as

well.

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Moving objects in the picture

Moving objects in the picture should normally be placed with space in front of the object,
i.e. where the subject can move into. This gives the viewer a feeling of space instead it would
give the viewer a claustrophobic feeling. Take a look at the examples to decide for yourself.

The jogger hardly gets any room to jog in the The jogger has plenty of room in front of her
first picture. and this picture

Placing horizon in the photo

Placing the horizon away from the centre can give a better effect than placing it in the
centre. Following the rule of thirds, if the horizon is placed on either the top or the bottom
horizontal lines, gives a good effect.

The boat and the horizon are The boat and horizon are The boat and horizon are
placed in the middle. This placed in the upper third placed in the lower third
gives a static feeling segment. segment
Among the 3 pictures the last photo looks the best as it gives more space to the boat and
the sky.

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As it is a good practice to place horizontals off centre, it is also best to place verticals off
centre. The following picture demonstrates that.
As you can see that the photo on
the left shows the pylon in the centre and it
focuses completely on the pylon and gives
no other details. Whereas the photo on the
right shows the pylon very well, even
though it is moved out of the centre, it also
shows more detail. The photo shows
diagonal lines which are more pleasing and
the composition gives more space to the
subject, resulting in a better photo.

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Digital Photography

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Digital photography today has taken over the world. 35 mm photography is now a dying
art. This does not mean that the concepts of photography have changed. The concepts that we
have discussed before remains the same. The most important change is that the films used in
35mm cameras have been replaced by memory cards. Unlike photographic films digital memory
cards can be used over and over again.
I have listed the differences between film cameras and digital cameras here

Film camera Digital camera

Capture medium Orthochromatic or panchromatic CCD or CMOS chips
films used
Capture format Film format (120, 135, 5 X 4, 10 pixel count, digital file type (RAW,
X 8) TIFF, JPEG)
Processing Film converted processed to Image is captured on memory card,
negative and then negative is from which images can be printed
processed to produce prints

CCD
CCD stands for Charge Coupled Devices. It is a chip which converts light into electricity.
This chip is used to draw the image from the light which falls on to it. Digital color cameras
generally use a Bayer mask over the CCD. Each square of four pixels has one filtered red, one
blue, and two green (the human eye is more sensitive to green than either red or blue). The result
of this is that luminance information is collected at every pixel, but the color resolution is lower
than the luminance resolution.

Better color separation can be reached by three-CCD devices (3CCD) and a dichroic
beam splitter prism that splits the image into red, green and blue components. Each of the three
CCDs is arranged to respond to a particular color. Some semi-professional digital video
camcorders (and most professionals) use this technique. Another advantage of 3CCD over a
Bayer mask device is higher quantum efficiency (and therefore higher light sensitivity for a given
aperture size). This is because in a 3CCD device most of the light entering the aperture is
captured by a sensor, while a Bayer mask absorbs a high proportion (about 2/3) of the light falling
on each CCD pixel.

Since a very-high-resolution CCD chip is very expensive as of 2005, a 3CCD high-

resolution still camera would be beyond the price range even of many professional
photographers. There are some high-end still cameras that use a rotating color filter to achieve
both color-fidelity and high-resolution. These multi-shot cameras are rare and can only
photograph objects that are not moving.

Pixel count
A digital photograph or digital image is made up of a number of dots placed horizontally
and vertically in a matrix across the entire frame. These dots are technically called pixels. The
number of pixels n for a given maximum resolution (w horizontal pixels by h vertical pixels) can be
found using the formula: n = wh. This yields e. g. 1.92 megapixels (= 1,920,000 pixels) for an
image of 1600 x 1200. The majority of compact (not SLR) digital cameras have a 4:3 aspect ratio,
i.e. width/height = 4/3.

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Resolution
Resolution provides an indication of the amount of detail that is captured, but, like the
other metrics, resolution is just another factor out of many in determining the quality of an image.
Furthermore, different methods of creating an image make it impossible to compare the
resolutions of cameras simply based on the number of pixels produced by the image sensor.
Another factor to be taken into consideration is that the relative increase in detail resulting
from an increase in resolution has to be judged based on the square roots of the resolutions. For
example, increasing resolution from 8 megapixels to 10 megapixels does not give an increase in
perceived detail of 25% as one might expect. Instead, compare the square root of 10 (3.16) with
the square root of 8 (2.83), and you can determine that the increase in perceived resolution is
only 12%, which is fairly difficult to see.

Sensor size and angle of view

Cameras with digital sensors that are smaller than the typical 35mm film size will have a
smaller field or angle of view when used with a lens of the same focal length. This is because
angle of view is a function of both focal length and the sensor or film size used.
If a sensor smaller than the full-frame 35mm film format is used, such as the use of APS-
C-sized digital sensors in DSLRs, then the field of view is cropped by the sensor to smaller than
the 35mm full-frame format's field of view. This narrowing of the field of view is often described in
terms of a focal length multliplier or crop factor, a factor by which a longer focal length lens would
be needed to get the same field of view on a full-frame camera.
If the digital sensor has approximately the same resolution (effective pixels per unit area)
as the 35mm film surface (24 x 36 mm), then the result is similar to taking the image from the film
camera and cutting it down (cropping) to the size of the sensor. For an APS-C size sensor, this
would be a reduction to approximately the center 50% of the image. The cheaper, non-SLR
models of digital cameras typically use much smaller sensor sizes and the reduction would be
greater.
If the digital sensor has a higher or lower density of pixels per unit area than the film
equivalent, then the amount of information captured will differ correspondingly. While resolution
can be estimated in pixels per unit area, the comparison is complex since most types of digital
sensor record only a single colour at each pixel location, and different types of film will have
different effective resolutions. There are various trade-offs involved, since larger sensors are
more expensive to manufacture and require larger lenses, while sensors with higher numbers of
pixels per unit area are likely to suffer higher noise levels.
For these reasons, it is possible to obtain cheap digital cameras with sensor sizes much
smaller than 35mm film, but with high pixel counts, that can still produce high-resolution images.
Such cameras are usually supplied with lenses that would be classed as extremely wide angle on

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a 35mm camera, and which can also be smaller size and less expensive, since there is a smaller
sensor to illuminate. For example, a camera with a 1/1.8" sensor has a 5.0x field of view crop,
and so a hypothetical 5-50mm zoom lens will produce images that look similar (again the
differences mentioned above are important) to those produced by a 35mm film camera with a 25
250mm lens, while being much more compact than such a lens for a 35mm camera since the
imaging circle is much smaller.

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What to look at while buying a SLR

Cost
Obviously. We need to look at how much we are willing to spend to get the features we
would need. A word of caution here. Sometimes we tend to buy the best we can depending on
how deep our pockets are. We consider how many features the camera has. Maybe we should
evaluate whether we need all the features that the most expensive camera has or the one which
is a little less expensive will do.
Remember, you will always get better results by going for a less expensive camera
mody and good lens instead of an expensive body and an ordinary lens.

Body
This is a very important because this is what you are going to hold in your hand. It has to
be comfortable in your palm. Check for the weight of the camera. It should not be too heavy for
you. Although heavy cameras are good as they have extra protection for the interior of the
camera, it should not be too much for you. You will see that all Nikon cameras are heavier than
their counterparts. Be it, Canon, Minolta and several others. This is because Nikon cameras
generally have a metal covering underneath the polymer cover. Check with the dealer about the
camera body or on the Internet or on leaflets about the camera.
Depending on your usage decide on the camera. If you would like to use your camera
like a pro then you would want to go for a camera with a sturdy body, which can take a few
knocks, be somewhat dust resistant.

Modes
Almost every autofocus SLR manufactured today comes with the 4 standard modes,
PSAM. Program mode (P) setting gives total control to the camera. The camera decides on the
exposure based on the certain program selected by the photographer, light conditions and the
library of similar photographs in its memory. Program mode can be of various types, Portrait,
Landscape, Macro, Night, High speed. All these program modes are for preset conditions. For
instance in Portrait mode the camera will use the largest aperture for getting the minimum depth
of field. In Landscape mode the camera will select an optimum aperture for getting maximum
depth of field. The mode descriptions are given in the camera manual.
Shutter priority mode (S) will allow the photographer to choose a shutter speed and once
the shutter speed is chosen the camera will decide on the aperture to be used.
Aperture priority mode (A) is similar to the shutter priority mode. Only difference being
that the aperture is set by the photographer while the shutter speed is decided by the camera.
Manual mode (M) gives full control to the photographer. With this setting the
photographer sets the aperture and shutter speed manually. The camera tells the photographer
whether the particular combination of aperture and shutter speed is under or over exposed. The
camera is fully overridden by the photographer in this case.

Metering modes
In all autofocus SLR cameras we find Centre weighted and Matrix metering (or its
equivalent). Only on medium to high-end cameras will we find Spot metering. This is not
absolutely necessary. Although it is definitely a bonus and at times it does help a lot. Spot
metering is used about 5-10% photographs.

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Introduction to Photography

Flash modes
Flash modes are available only from medium range SLR s. Those cameras can alter the
flash output power, allow slow flash synch, rear curtain synch. These modes are quite important
while shooting with the built in flash. Dedicated flashes have these features built in and can be
controlled from the camera settings, but these features cannot be used by all 3rd party
manufactured flash.
These features are also a bonus and not absolutely necessary. These features will be
used about 40-50% in flash photography.

Miscellanous modes
These modes are found in medium to high-end cameras. All these features are quite
helpful though.
• Depth of field preview.
This button allows the photographer to view the depth of field at the aperture set.
Normally when we look through the camera, the lens is kept at maximum aperture. This
is done to allow the maximum amount of light through the lens for the best possible view.
So if the maximum aperture of the lens is f/4 and the aperture set for the photograph is
f/8 then the depth of field can be checked by using the DOF button. What happens then,
is that the aperture is actually set to that aperture and so the DOF can be seen.

• Multiple exposure mode

This feature allows the photographer to take more than one shot on a single frame.

I hope this document has given you an insight into photography and it
has instilled enough interest in you to take your knowledge further. I might
have missed something in the document or there might be something you
would like me to clarify. I would be very happy to receive your feedback,
comments and/or queries at abhijit673@gmail.com .

You can also comment on abhijit673 @

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