Photography concepts Giáo trình photography basic Arena Multimedia

Photography concepts Giáo trình photography basic Arena Multimedia Photography concepts Giáo trình photography basic Arena Multimedia Photography concepts Giáo trình photography basic Arena Multimedia Photography concepts Giáo trình photography basic Arena Multimedia Photography concepts Giáo trình photography basic Arena Multimedia

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Photography Concepts © 2020 Aptech Limited

All rights reserved

No part of this book may be reproduced or copied in any form or by any means — graphic, electronic, or mechanical, including photocopying, recording, taping, or storing in information retrieval system or sent or transferred without the prior written permission of copyright owner Aptech Limited

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Preface

This module teaches the students basics of digital photography It introduces them to the different types of camera and its controls Lighting plays an important role in photography and hence the students would be briefed on the same along with composition techniques to enhance their skills

The ARENA Design team has designed this course keeping in mind that motivation coupled with relevant training and methodology can bring out the best The team will be glad to receive your feedback, suggestions, and recommendations for improvement of the book

Please feel free to send your feedback to the ARENA Design team at the Head Office, Mumbai

ARENA Design Team

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Table of Contents

Session 01: Basics of Digital Photography What is digital photography?

Uses of Digital Photography History

Digital over analog photography Career in digital photography Types of digital cameras Lenses Tackling flaring and ghosting Precautions Camera Controls Capturing images Continuous Photography Image formats Photography in Full Auto Mode Image sensor Summary Exercise Session 02: Lighting Direction of Light Direct and indirect light Frontal lighting Sidelighting Backlighting Changing the lights and conditions Dawn to dusk

Silhouettes and their impact Season related changes Low light photography Drama in light

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Session 1

Basics of Digital Photography

Learning Outcomes

In this session, you will learn to: > Define digital photography

> Describe various types of cameras > State various image formats

1.1 What is Digital Photography?

Digital photography is a photography technique in which the camera uses electronic photo detectors to capture the image instead of a traditional photographic film Optical lenses are used to focus the image on the photo detectors The image captured by these photo detectors is stored as a digital file, which can be further processed in the computer using photo-editing software

Until the invention of this technology, photographs were taken by exposing light onto the photosensitive photographic film, which were then processed in chemical solutions to develop the images No wet- bath is involved in digital photography, just a connecting data cable and a color printer gets the job done

Digital cameras capture images that are in a universally recognizable digital format that makes them easier to manage, display, and share You can insert digital photographs into PowerPoint presentations or word processing documents, print them on any material using a printer, exchange them via e-mail, and integrate them into video making software to be played on the Television, post them on a social media or any Website where anyone in the world can view them

1.2 Uses of Digital Photography

Digital photography is used wherever we have to deal with modern day images such as: ¢ Digital standalone cameras

e Digital cameras in mobile phones, tablets, and laptops e Digital scanners and printers

e Emails

e Power point presentations e Web publishing

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1.3 History

Digital photography started in astronomy when the first spacecraft image of Mars was taken in 1965 It used a video camera tube and a digitizer to produce a digital image First attempt for building a digital camera was done in 1975 using solid-state Charge-coupled Device (CCD) image sensor chips This camera weighted around 3.6 Kgs; it recorded the captured images to a cassette tape with a resolution of 0.01 megapixels It captured its first image in December 1975 in 23 seconds Although, it was a prototype and was not intended for mass production

Fuji's DS-1P was the first true digital camera, which stored the recorded digital images to a 16 MB internal memory card using a battery to maintain the data in the memory card However, this camera never made out of Japan

Dycam Model 1 made in 1991 was the first commercially available digital camera It used Charge- coupled Devices (CCD) as image sensor, stored images in digital format, and can connect to a computer for downloading captured images

COLLABORATIVE LEARNING

GROUPS

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1.4 Digital over Film Photography

The digital photography has replaced the film-based photography in less than a decade due to the following reasons: > Digital photography saves money, as you do not have to buy the photo films and pay for their development

Saves time as there is no need to take trips to the photography studio for developing and the development process itself takes much more time as compared to digital printing

Images can be previewed in the digital camera itself

Modern digital cameras can even record audio and video along with images

Modern digital cameras comes with built-in features such as image cropping, red-eye reduction, and enhance color and contrast

The images can be printed on the pages of a bound book, such as those send in the bookstores Digital images follow universal encoding mechanisms (jpg, png, and gif), so the pictures clicked by a digital camera can be instantly shared to any computer in the world-using Internet or can have them posted on the social media Websites

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1.5 Career in Digital Photography

Today, we live in a digital world and digital photography has become the essence of digital representation The demands for photography have also been increased, as photos are the best way to create and store memories However, apart from just creating memories, digital photography is being used in the following fields, which will earn you a good amount of money

» Brand endorsement photo-shoots: This is the biggest market for professional photographers These photo-shoots include photographing models (male and female) for representing the brand, photographing the actual product under different lighting and surrounding conditions, and photographing the celebrities who are the brand ambassadors

> Personal portfolio: This is particularly important for the people who are in modelling and acting fields

> Social events: These include all marriage related photo-shoots (pre-wedding, in-wedding and post- wedding) photo-shoots, birthday parties, social gatherings, receptions, and the list goes on » Wildlife photography: It is a very big field and includes clicking photos of animals and their life in

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1.6 Types of Digital Cameras

Digital cameras come in different sizes and configurations, from pocket sized to larger professional cameras Following are some of the common types for digital cameras:

» Point and shoot: These are pocket-sized cameras and have fewer controls and features than bigger cameras These cameras capture very good quality images and due to its size, many are likely to have it Point and shoot cameras are used in mobile phones, but the problem with them is that they cannot match the quality of dedicated cameras Refer to Figure 1.1 T»Š«-SS« SOJOOO DIGITAL em Poe

Figure 1.1: Point and Shoot Camera

> Fixed lens cameras: These cameras have a high quality fixed zoom lens and shares many exposure and focus control features of the SLR cameras Refer to Figure 1.2

Figure 1.2: Fixed Lens Camera

» Digital Single-lens Reflex (DSLR) cameras: DSLR cameras are the most popular amongst professionals Refer to Figure 1.3 These are full-feature cameras and are expensive They have the following advantages over other camera types:

e You can change the camera lens

e They have quick focus and click images with less noise

e You have the feature to scene through the lens to adjust the fine details of the image e There is a wide variety of accessories to choose from, including lens, external flashes,

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Figure 1.3: DSLR

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1.7 Lenses

1.7.1 Characteristics of SLR camera

The Single-lens Reflex (SLR) camera's construction allows it to use a wide variety of interchangeable lenses for obtaining optimal photography One of the distinguishing characteristic of SLR camera is the viewfinder system As the image that reaches the focal plane can be viewed using the viewfinder, the image which is to be captured can be checked in prior

A mirror in front of the lens is used to deflect the light rays, which pass through in upward direction to be shown on a focusing screen The deflected image is then correctly oriented and projected by using a pentaprism before it is seen through the eyepiece Upon pressing the shutter button, the mirror rises up exposing the film to the image sensor The mirror then returns to its original position once the shutter is closed

This system enables the photographer to accurately frame the images without being affected by parallax phenomenon, which has different light paths for the viewfinder and shooting lens

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1.7.2 Different Focal Lengths for Different Images

The impression of a photograph can be varied largely by using a variety of lenses for serving different purposes The differences in the lens focal length substantially changes the angle of view (range), depth of field, and perspective of the subject to be photographed

The angle of view is called as the angle of range and it is generally shown as the angle of the diagonal direction Normally, the image taken by the lens is circular and is called as an image circle The actual photographed image is taken from the center of the image circle Refer to Figure 1.4

In case of a camera having a 35mm lens, the angle of view (diagonal) is generally of 180° using a 15mm fisheye lens, 46° for 50mm lens, 24° for 100mm lens, 12° for 200mm, and 4° for 600mm telephoto lens It means, the longer the focal length, the narrower is the angle of view Photo 4 Figure 1.5: Lens Focal Length © Canon Inc 2003

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1.7.3 Depth of Field

The depth of field is the range of the focus in front and behind of the subject The depth of field is substantially influenced by the change in focal length, position in focus, aperture setting, distance of photographing, and the distance between the subject to be photographed and background Smaller aperture results in deeper depth of field and larger aperture results in shallower depth of field

Refer to Figure 1.6 Here you will notice that under the same shooting conditions, the depth of the field becomes wider with decrease in aperture The focal range is a ratio of approx 1:2 It means the range is shallower in the front and deeper behind the actual focusing distance (0000000 wwww Preece ke Ũ ay 2v ^ a E- ke Aaa2222244

Figure 1.6: Depth of Field (© Canon Inc 2003)

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1.7.4 Perspective matters

Effective use of perspective for creating dynamic wide-angle photos and effects with telephoto lens allows it to produce expressive photographs with good impact The perspective visual effect determines how close or far the background appears from the subject The shorter the focal length of the lens, the more perspective effect is expressed and the less compressed the photograph looks, on the other hand, the longer the lens's focal length, the less this effect is expressed and the photograph looks more compressed

16mm 24mm

Figure 1.7: Wide-angle Lenses (® Canon lnc 2003)

Figure 1.7 illustrates a series of images photographed by changing the shooting distance, while keeping the subject of the same size makes this effect apparently visible It is quite easy to look how the perspective is greatly changed depending on the lens focal length

After comparing the 16mm and 200mm photographs in Figure 1.7 using wide-angle lens, it appears as if the background is stretching out behind the subject On the contrary, using a telephoto lens, there appears to be very little distance between the subject and background, which gives the photograph a compressed appearance

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1.8 Tackling Flaring and Ghosting

1.8.1 Reflective Characteristics of Image Sensors

The reflective characteristics of image sensors uses in digital camera differs from those used in film cameras Image sensors in film cameras possess a higher amount of reflectivity known as mirror reflection, which creates flaring and ghosting effect inside the lens when light from a bright source enters the lens and reflects back to the image sensor Refer to Figure 1.8 (a)

1.8.2 Use of Meniscus Lens

If you ever go for a racing event, you will notice that both the stadium and the racing cars are brightly lit The sources of light are lighting in the stands and the headlights of the cars This provides multiple sources of bright light Ordinary telephoto lenses consist of protective glass in front of the lens If the glass is flat, any light, which enters the lens from the bright light source, will be reflected from the image sensor and back inside of the protective element, which causes spot-shaped ghosting To prevent such situations, meniscus lenses are used as the protective glass on large aperture telephoto lenses These are spherical lenses having the same curvature on both sides of the lens, so the light reflected off the image sensor forms an image in front of the image sensor and then is dispersed By such, the light, which is dispersed, does not hit the reflective elements of sensor preventing ghosting while getting high level of contrast at the same time Refer to Figure 1.8 (b) and Figure 1.8 (c)

Figure 1.8 (a): With Meniscus Lens Figure 1.8 (b): Without Meniscus Lens Spherical protoctve glass (meniacus lea)

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1.9 Precautions

Digital camera is a sensitive gadget and some precautions need to be taken in order to prevent any unwanted disturbances in the images taken

1.9.1 Don’t Depend on Computer

The computer is used as a post-processing tool to adjust the image's sharpness, contrast, brightness, and other factors However, you need to avoid becoming over-dependent on your computer because a drop in the image quality accompanies most of the image processing For taking good photographs, it is very important to set proper exposure, focus settings, and prevent the camera from shaking It will be safe if you only rely on the computer for the final touch-ups

Often, it is difficult to achieve better results than the original photograph by editing the image on the computer, especially with JPEG formats, as these are the processed images developed by the camera's image processing software You can use the RAW format to process the image on the computer using software packages such as adobe lightroom, adobe Photoshop, coral draw, and so on Using this process, you can manipulate the image without having a drop in the image quality, even if the same image is processed over-and-over again However, no amount of post-processing can fix a picture that was taken at wrong exposure, aperture, out of focus, or if the camera shook while taking the picture

1.9.2 Prevention from Dust

Changing the lens on windy and dusty places can cause dirt to enter and settle into the camera through the lens mount The dust on the image sensor may appear as black smudges or specks on the image In order to avoid this, you need to do the following:

e Change the lens as quickly as possible where there is no wind e Always attach the body and lens cap when not in use

e Change the lenses with the camera mount faced down e Check for dust getting inside the body and lens cap

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1.10 Camera Controls

You can change the settings of your camera, by using menu commands or using a combination of button and dials on the camera, Menu commands require you to go in the main menu which makes them slower to use and difficult to use in bright light when you cannot read the monitor screen You are also required to learn them or the menu sequence required for a specific control Buttons and dials are faster as they are physically present on the camera body You can get familiar with them to use without even having to look over them, but initially these functions are harder to remember

Most of the modern day cameras use a combination of both approaches by putting the most frequently used functions on the dials and less frequently used on the menus A recent addition to the button/dial system is a dial with four points Pressing any point or rotating the dial (in some cases), moves the menu highlight up, down, sideways, or enables you to control images in playback mode There is a Jjoystick-like lever in the middle of these four buttons which acts as a enter key to complete the command The LCD monitors on high-end cameras are opting for touch screen, which makes the menu selection, image playback, Zoom, and management easier

However, many cameras share the same functionality, their buttons and dials vary from camera to camera Here are some of the controls that are common to all cameras

> Zoom lever: These buttons enables you to zoom through the lens However, on SLR camera you zoom using the ring on the lens

w Shutter button: It locks the focus and exposure when pressed halfway down, and shoots the picture when pressed fully

» Continuous / self-timer button: It sets the camera to shoot sequence of images or turns ON or OFF the self-timer

» Mode dial: Allows you to select various modes of shooting such as programmed or automatic » ON/OFF button: This button or lever turns the camera ON or OFF

» Flash button: Selects the desired flash modes

» Menu button: Displays or hides the menu controls on the monitor

» Print/Share Button: Allows you to download or print the images when connected to a computer or printer

» Delete button: It deletes the selected image in playback mode

Though the mentioned controls are mostly common to all of the cameras, you still need to go through the camera manual to get to know about their specific controls

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1.11 Capturing Images

The famous photographs are those, which capture that decisive movement when seemingly unrelated actions intersect at a single point to make an optimal photograph For this, the photographer always needs to be ready and his camera too Most of the today's digital cameras have automatic focus and exposure systems that free you from the worry of controls However, these cameras have other sets of problems that makes those decisive moments hard to capture Many of these have been eliminated on the expensive cameras

The most important hurdle that has many photographers distraction is the delay between pressing of the shutter button and the camera actually clicking the picture This and some other types of delays built into digital cameras have an effect on your ability to capture fleeting expressions or respond to fast actions while taking pictures

> Start-up time: It is how long it takes you to click a photo after turning ON the camera

» Shutter-lag time: It is the delay between pressing the shutter button and the camera actually capturing the image This delay occurs as the camera takes time to clear the image sensor, set the exposure and focus the image before firing the flash, set white balance for correction in color, and then take the picture The top of the line cameras almost have no lag

» Processing delay: It occurs as a picture is processed in the camera and stored in the memory This delay becomes more evident when using noise reduction This delay has been substantially reduced by the use of buffer memory Images are temporarily stored in the buffer because the storage and retrieval-using buffer is faster enough

» Flash recycle delay: It occurs after taking a series of photos using flash In such case, you have to wait until the flash recycles

v Viewfinder blackout: While taking a picture using a DSLR, its mirror goes up so the light can fall upon the image sensor While it is up, you cannot see through the viewfinder

In order to decrease most of the delays associated with capturing action shots, compose the image and press the shutter key halfway down to lock the focus and exposure You can continue to hold it down until the anticipated actions completes and then press it rest of the time to take the picture, though this drains the batteries faster The camera shoots immediately as the exposure and focus have already been calculated in advance

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1.12 Continuous Photography

In most of the situations, normally you take one photo at a time However, for some situations, you can also capture sequence of photos in a mode known as continuous mode In this mode, you just need to press the shutter button and the images are captured one after another until you release the button The number of images captured in a single burst is usually dependent on the camera's buffer With smaller cameras, where there is less or no buffer, the camera may use a smaller image size as it reduces the processing and storage time

Once a sequence is captured, you can choose the best image from the sequence or use all of them to create an animation clip, or join a series of sequences together into a short movie clip

1.13 Image Formats

Choosing the appropriate image file format is one of the most important workflow related decisions All cameras allow you to use the JPEG file format by default, but they may also let you use higher quality RAW format Many of the modern cameras support different formats such as TIFF, DNG, and PNG » JPEG: It is the default format used by all the cameras This format most often lets you specify both,

the image size and compression When you capture an image in this format, the processor chip in the camera manipulates it based on the specified settings and then compresses it to reduce its size Once the changes to the image are done, they cannot be undone Some of the original data in the image is lost for good

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» Digital Negative (DNG) format: Most of the camera companies have developed various and frequently changing RAW file formats In addition, the manufacturers keep secret about their specifications so that there are always RAW files your computer software cannot read This lag in time and inconvenience to users can lead to the doorstep of the camera companies One possible solution for this problem is the Digital Negative (DNG) introduced by adobe technologies This format is publicly defined and openly shared for RAW files is an attempt for ensuring that you will be able to access your RAW files in future In case your camera does not capture RAW images in DNG format, then you can convert them to DNG using adobe Lightroom or Photoshop This format is supported by all adobe products related to photo editing, some of the software companies, and a number of camera manufacturing companies

>» Tagged Image File Format (TIFF): It is often used to exchange files between applications and computers This format is supported by almost all image editing, paint, and page layout applications These files tend to be larger than both RAW and JPEG images and can be saved either by using 8 bits or 16 bits per color

1.13.1 Choosing Between Formats

When making a choice between JPEG and RAW formats, you need to consider some things about each format As it’s very hard for you to add pixels and retain image quality, or remove the compression effects, so it is usually the best option to use the largest available JPEG size with least available compression In future, if you have to reduce the either, then it can be done later by using a photo- editing software If the image is shot at a lower quality then you cannot improve it much or get a large, sharp print The only problem associated with this approach is that the higher quality images have larger file sizes,

RAW images are always captured at the largest possible file sizes and the compression system used in this is lossless Images in this format previously used to require an extra processing step, but since, the re-designing of latest programs such as adobe Lightroom and Aperture after the introduction of RAW format, the camera can handle these formats as they can handle JPEGs Using RAW format comes with some advantages:

» RAW lets you decide on most of the camera settings after the picture is taken, not before For example, when you capture a JPEG image, under fluorescent lighting, the camera adjusts the image in order to remove the yellow-green tint Any changes done later are on top of this initial change On the other hand, if you use capture the image in RAW format, then the camera just captures the image as it is and you have to decide on what white balance settings to use later on You can also create different versions of the same image, each with having its own white balance » RAW images can be processed on a later date when new and improved applications come to the

market

» You can generate duplicate or alternate versions of the same RAW image Admittedly, there are also some drawbacks to using RAW images:

» RAW files are quite large

» You may have to wait longer between consecutive shots because the buffer memory fills more quickly and the camera is busy in processing of the last image you shot, and moving the image from the buffer to the memory card

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1.14 Photography in Full Auto Mode

All the digital cameras have an automatic mode that sets focus and exposure for you With the camera set in this mode, the only thing you have to do is to frame the image and hard-press the shutter button This mode is ideal in many of the situations, as you have to focus on the subject and not on the camera Here are some things to do when using camera in auto mode on almost any digital camera:

» Getting the camera ready: You have to turn the camera ON and set it to auto mode To save the batteries, you can possibly turn OFF the monitor screen and compose your image using the viewfinder When using for first time, make sure you have entered the memory card and set the date and time The date and time helps you to organize, locate, and identify images later

» Check settings: Itis important to check the camera settings at the beginning of a session You have to notice how many pictures you can take at the current camera settings and the status of the battery You also have to learn what any icons mean as it is not unusual to change a setting, then forget you have done so Some of these settings remains changed even though you switch OFF the camera and turn it ON again and affect all the subsequent pictures

» Holding the camera: When taking pictures, you have to hold the camera in your right hand while supporting the lens with the left hand Be sure you do not block the sensors, flash, or lens

v Framing the image: Use the monitor screen, or viewfinder to compose the scene you wish to capture

Figure 1.9: Auto Focus Area

As illustrated in Figure 1.9, some digital cameras have more than one focus areas and the one being used is lit up or blinks on pressing the shutter button halfway down (see top arrow) When the focus locks, an indicator lit up (see bottom arrow) and the camera may beep

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Auto-exposure: The job of the exposure system is to measure the light reflecting from various parts of the scene and then uses these readings to evaluate and set the best possible exposure This happens at the same time when you press the shutter key halfway down to lock the focus Auto-flash: In dim light conditions, the auto exposure system will usually fire the camera's in-built flash to illuminate the scene In case the flash is going to fire, the flash device pops up or the flash light glows on pressing the shutter key halfway down

Auto White Balance (AWB): As the color characteristics in a photo is affected by the color of the light source illuminating the scene, the camera automatically adjusts the white balance in order to make white objects in the scene look white in the photo

Taking the picture: The shutter key has two associated stages, when you press it halfway down, the camera locks the exposure and focus and the camera beeps or an indicator starts lighting (If the indicator blinks then the camera is having trouble focusing) After focusing, press the shutter button all the way down to click the picture

Image review: Many of the cameras briefly display the image immediately after it has been captured This lets you to decide if the image is good enough or it needs to be reshot

GROUPS

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1.15 Image Sensor

Digital cameras, though of modern technology have their roots going back for almost 200 years With the very first camera, all have been black boxes having a lens to focus on the image, an aperture to determine how bright the light is, and a shutter to determine how long the light enters The difference between traditional film and digital cameras is how they capture the image Digital cameras use a solid- state device called as an image sensor In some digital cameras, the image sensor used is a Charge- coupled Device (CCD), while in others they use a Complementary Metal-oxide Semiconductor (CMOS) sensor Both types of sensors can give very good results They are millions of photosensitive diodes on the surface of these silicon chips, each of which captures a single pixel of the desired photograph While taking a picture, the camera's shutter opens for a brief period and then each pixel on this chip records the brightness of the light that falls on it by accumulating its photons The more light that falls on the pixel, the more photons it records The pixels capturing light from picture highlight will have many photons On the other hand, those pixels capturing light from shadow areas will have fewer

When the shutter closes to end the exposure, the photons from each of the pixel are counted and converted into a digital number This series is then used to reconstruct the image by setting the color and brightness of the matching pixels on the screen or the printed page

1.15.1 Image Size

While capturing an image, the number of pixels used to it (referred as pixel count or resolution) has an important effect on how large it can be printed or displayed on the screen At any given image size, more number of pixels adds detail and sharpen the image edges Numbers matters, so the best possible approach is to shoot using the largest available image size You always have the option to make an image smaller using photo-editing software, but you never stretch it while retaining its original quality Refer to Figure 1.10

@-oC Figure 1.10: Image Size

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Figure 1.11: Pixelization

Another advantage of large images is seen while editing Not only can you crop these images more, changes to the aspects such as color balance, saturation, hue, brightness, and contrast are more effective on larger images there is more image data available to work with When these adjustments are done, you can reduce the image file to the required size

However, the cost rises as the image sensor size increases Although larger sensors can provide you with sharper and better enlargements, more number of pixels also means larger image files Not only the larger files occupies more storage space, the take longer to get transferred, process, edit, and are often too large to e-mail or post on a Website Medium image sizes such as 800 x 600 are perfect for email attachments, Web publishing, small prints in your own presentations and documents For such uses, the higher resolution of images just increases the file sizes without significantly improving the image quality

1.15.2 Sensor size and aspect ratios

The image sensor used in a camera has two related and important physical characteristics — its size and aspect ratio

* Sensor Size: Image sensors comes in a wide variety of sizes with the smallest size sensors used in point and shoot cameras, and the largest in professional cameras (SLRs) Often, consumer SLRs use sensors having the size as same as the frame of an Advanced Photo System (APS) film Professional SLR cameras occasionally have sensors of the same size as the frame of 35mm film — known as full-frame sensors (Even larger sensors are used for large format cameras)

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Refer to Table 1.1 for commonly used sensor sizes:

Size Width (mm) Height (mm) Used in

1⁄4 3.2 2.4 Point & Shoot Cameras 1⁄3 4.8 3.6 Point & Shoot Cameras 1/2 8 6.4 Point & Shoot Cameras 2/3 11 8.8 Point & Shoot Cameras A 16 12.8 Point & Shoot Cameras APS-C 22.2 14.8 Consumer SLRs Full frame 36 24 Professional SLRs

« Aspect Ratio: The ratio of the sensor's width to height is called as aspect ratio Image sensors come in a variety of aspect ratios A square has a ratio of 1:1 (width = height) and that of a 35mm film is of 1:5:1 (1 ¥% times wider than its height) Most of the image sensors fall within these extreme sizes A sensor's aspect ratio is important because it determines the shape and proportions of the photographs you take In case an image have different aspect ratio than the device it's printed or displayed on, it has to be resized or cropped to fit in The option left with you is to crop a part of the image, put in waste the part of the paper, or display area To have a better perspective, try printing a square image on a rectangular sheet of a paper so that either the entire image is printed or the entire paper is filled Refer to Table 1.2 for aspect ratio for various mediums of display

Table 1.1: Sensor Size Image Width x Height Aspect Ratio 35mm film 36x24 1.50 Computer display 1024 x 768 1.33 Canon 5D 4368 x 2912 1.50 Canon S3 IS 2816 x 2112 1.33 Photo paper 4x6 1.50 Printing paper 85x11 1.29 HDTV 16x9 1.80

For calculating the aspect ratio of any camera, divide the largest number in its resolution by the smallest number Suppose, if a sensor has a resolution of about 4368 x 2912, and then divide the former by later So, the aspect ratio in this case is 1.5, it's the same as a 35mm film but is different from an 8.5 x 11 sheet of paper

Table 1.2: Aspect Ratio

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1.16 Summary In this session, Basics of Digital Photography, you learned that: > v v v v

Digital cameras capture images that are in a universally recognizable digital format that makes them easier to manage, display, and share

Fuji's DS-1P was the first true digital camera, which stored the recorded digital images to a 16 MB internal memory card using a battery to maintain the data in the memory card

Digital cameras come in different sizes and configurations, from pocket sized to larger professional cameras

Video cameras are primarily used for recording long and continuous videos

The Single-lens Reflex (SLR) camera's construction allows it to use a wide variety of interchangeable lenses for obtaining optimal photography

The angle of view is called as the angle of range, and it is generally shown as the angle of the diagonal direction

Effective use of perspective for creating dynamic wide-angle photos and effects with telephoto lens allows it to produce expressive photographs with good impact

The reflective characteristic of image sensors uses in digital camera differs from those used in film cameras

The computer is used as a post-processing tool to adjust the image's sharpness, contrast, brightness and other factors

Arecent addition to the button/dial system is a dial with four points

Once a sequence is captured, you can choose the best image from the sequence or use all of them to create an animation clip, or join a series of sequences together into a short movie clip When making a choice between JPEG and RAW formats, you need to consider some things about each format

Some digital cameras have more than one focus areas and the one being used gets lit up or blinks on pressing the shutter button halfway down

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Session 2

Lighting

Learning Outcomes

In this session, you will learn to: » Describe various types of lighting > State the impact of silhouettes

> Explain effect of seasonal changes on lighting

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2.1 Direction of Light

The type of light illuminating your subject has a profound effect on the feel and success of the photograph In digital photography, it is not the amount of light that really matters Long shutter is used during low light conditions when light rays reach the camera's sensor Actually, the quality of lighting transforms an ordinary shot into a great picture

There are several factors that contribute to the quality of lighting, but the easiest way is to change the direction of light source relative to the subject This determines where actually the shadows fall and which parts of the subject are actually lit

For simplicity purposes, photographers generally talk about three broad categories of lighting directions Frontal lighting — in this, the light can be in front of the subject, backlighting — light can be behind the subject, or side lighting — the light can be to the side of the subject Each type of lighting has its own effect on the light

> Frontal lighting: The sun coming from behind the photographer evenly lights the building in Figure 2.1 This sort of lighting is better for accentuating color, as seen in the red color of brickwork and blue color of the sky

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Backlighting: In Figure 2.2, most of the scene is illuminated indirectly by the backlighting However, the narrow beam of light coming from the arch brings that part of the scene alive, revealing the texture of the archway

Figure 2.2: Backlighting

The light falling on the subject can come from any angle As many of the pictures are taken during daylight, so the angle it comes from can vary by 360 degrees around the subject, and through 180 degrees arc depending on the sun's height In the photography studio, the subject can also be lit from below or any other angle

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v

Additionally in outdoor photography, it is important to realize that although shadow areas are not lit directly, they are also not in complete darkness Even in shade, the subjects are lit indirectly by the rays reflected by the sun

Mixed directions: The ramp in Figure 2.3 is lit by natural sunlight coming from the side and back Most of ramp is in semi-shadow areas and lit only by soft and reflected light However, most of it is bathed in strong direct sunlight

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» Side lighting: Direct side lighting from any source typically creates both strong highlights and shadows In Figure 2.4, you can see some parts of the red chili in detail, whereas some of its parts are in total darkness

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2.2 Direct and Indirect Light

Though, light travels in straight lines, its path from the source to the subject is not always in straight line Light can be diffused by clouds, fog, dust, or reflected by surfaces, which causes it to scatter and soften its effect The degree to which this light is softened in such ways can be significant in the final image Diffuse and indirect light gives and even illumination with less distinct shadows The bold and strong characteristics associated by side lighting, are subtler, for example, when the light is diffused due to cloud cover, then they would be on a clear sunny day This kind of soft lighting is suitable for some subject, but others look better with a less diffused, more direct illumination The degree of such illumination is variable offering almost infinite number of permutations

2.2.1 Squinting and Direct Sunlight

The type of light you use usually does not change the subject, but the way it appears in the photograph With portraits, however, this is not the case Direct and bright sunlight will tend people to squint, as shown in Figure 2.5a In addition, unwanted shadows appear in the eye sockets and under the nose Due to these reasons, it is best to use diffuse lighting for portraits whenever possible If necessary, make the person stand in the area of shadow to produces a more natural expression, as shown in Figure 2.5b In case of deep shadows, you can alter the image characteristics during post-processing

on your computer

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2.3 Frontal Lighting

One of the safest ways to take a successful photograph is with the sun behind you This is because majority of shadows are thrown out of the view, behind the subject, and the surfaces are evenly lit This lighting maximizes visible detail in the scene and when it is direct, it provides the strongest color saturation

However, the main drawback of frontal lighting is lack of shadows, which means it cannot provide strong clues to form and texture It is lit from straight on; the buildings can look such as 2-D cutouts Therefore, itis better to use frontal lighting when the sun is over your shoulder, rather than behind you This change in the lighting angle provides you with sufficient shading to add some feeling of form and depth Unlike backlighting and sidelighting, frontal lighting creates a scene having a contrast range that can be easily managed by digital camera That is, the automatic exposure systems work well, without the need for manual overrides

> Facing the sun: With the late afternoon sun behind the photographer, its light provided great richness in the color of this portrait of an oil derrick (Refer to Figure 2.6) However, although, its shape is distinct, its form is not well defined

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2.4 Sidelighting

Photography with the light to the side of the camera adds drama in the scene, perhaps a complex pattern of light and shade Some of the areas are well lit, and even shows good color saturation, while others are in shadow, hiding both details and color These boundaries between the dark and light are especially good at revealing the 3-D form of a subject

Depending on the surface texture, this direction of lighting can also be excellent for revealing the surface texture The real difficulty of that the shadows often end up obscuring important details In addition, with the more complex forms, the more difficult it becomes to use the sidelighting successfully Even for simple, and more identifiable objects, sidelighting works best when it is tempered, for example, when its softened by clouds, to make the contrast between light and dark less intense

In photography studios, sidelighting is not just diffused, but it is used in combination with reflectors that precisely manage the contrast across the subject

> Contour Accentuation: Sidelighting coming from an off-camera flash shows the details of the sculpture (Refer to Figure 2.7), while a reflector to the left controls the shadows

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» Rounds and curves: Simple contours and forms dwell good with sidelighting In Figure 2.8, it has been used to emphasize the solidity of the round tomb and beautifully carved arches of the palace