While you won’t find it printed on any calendar, 2009 marks a quiet anniversary for the program that you, and many other graphic designers, probably use the most. It was 20 years ago in February that Adobe shipped version 1.0 of Photoshop – still its most popular (and lucrative) application, and possibly the only bit of software to have spawned its own verb form.

But the true origins of Photoshop go back even further. The program whose splash screen now displays 41 names was originally the product of just two brothers, Thomas and John Knoll, as fascinated by technology as they were by art. It was a trait they’d inherited from their father, a photography buff with his own personal darkroom in the basement and a penchant for early home computers.

Thus Thomas dabbled with photography, learning about colour correction and contrast in the darkroom, while John happily tinkered with his dad’s Apple II computer. When their dad – clearly an early adopter – bought one of the first Macs on the market in 1984, both were bowled over by its capabilities. Yet ironically it was its frustrating inadequacies that would eventually lead to the multi-million dollar application sitting on nearly everyone’s hard drive today.

In the beginning
By 1987, John Knoll was working at Industrial Light and Magic – Lucas film’s nascent special effects division, founded for Star Wars – while Thomas was studying for his Ph.D. on image processing at the University of Michigan. Having just bought a brand-new Apple Mac Plus to help out with his thesis, he was dismayed to find it couldn’t display greyscale images on the monochrome monitor. So, in true hacker style, he set about writing his own code to do the job.

Unsurprisingly, John was also working on image processing at ILM, and during a holiday visit he became very impressed with Thomas’s progress. Thus the pair began to collaborate on a larger, more cohesive application, which they dubbed – excitingly – Display.

It wasn’t long before John had bought a new colour Macintosh II and persuaded Thomas to rewrite Display to work in colour. Indeed, the more John saw of Display, the more features he began to ask for: gamma correction, loading and saving other file formats, and so on.

Although this work distracted Thomas from his thesis, he was quite happy to oblige. He also developed an innovative method of selecting and affecting only certain parts of the image, as well as a set of image-processing routines – which would later become plug-ins. A feature for adjusting tones (Levels) also emerged, along with controls for balance, hue and saturation. These were the defining features of Photoshop, but at the time, it was almost unthinkable to see them anywhere outside of specialist processing software in a lab – or at ILM.

By 1988, Display had become ImagePro and was sufficiently advanced that John thought they might have a chance at selling it as a commercial application. Thomas was reluctant: he still hadn’t finished his thesis, and creating a full-blown app would take a lot of work. But once John had checked out the competition, of which there was very little, they realised ImagePro was way ahead of anything currently available.

From ImagePro to Photoshop
Thus the search began for investors. It didn’t help that Thomas kept changing the name of the software, only to find a name was already in use elsewhere. No one is quite sure where the name ‘Photoshop’ originally came from, but legend has it that it was suggested by a potential publisher during a demo, and just stuck. Incidentally, splash screens from very early versions show the name as ‘Photoshop’ – which seems far more in line with today’s craze for Extraneous Capitalisation.

Remarkably in retrospect, most software companies turned their corporate noses up at Photoshop, or were already developing similar applications of their own. Only Adobe was prepared to take it on, but a suitable deal wasn’t forthcoming. Eventually, though, a scanner manufacturer called Barneyscan decided to bundle it with its scanners, and a small number of copies went out under the name Barneyscan XP.

Fortunately for the future of digital imaging, this wasn’t a long-term deal, and John soon returned to Adobe to drum up more interest. There he met Russell Brown, then Art Director, who was highly impressed with the program and persuaded the company to take it on. Whether through naivety on Adobe’s part or canniness on the brothers’, Photoshop was not sold wholesale but only licensed and distributed, with royalties still going to the Knolls.

It wasn’t as if this deal meant the Knoll brothers could sit back and relax; if anything, they now had to work even harder on getting Photoshop ready for an official, 1.0 version release. Thomas continued developing all the main application code, while John contributed plug-ins separately, to the dismay of some of the Adobe staff who viewed these as little more than gimmicks.

Curiously, this attitude still remains among some purists, who claim that most Photoshop plug-ins are somehow ‘cheating’ and not be touched under any circumstances, while others swear by their flexibility and power when used properly.

As in the program’s formative days, there were always new features to be added, and somehow Thomas had to make time to code them. With the encouragement of John, Russell Brown – soon to become Photoshop’s biggest evangelist – and other creatives at Adobe, the application slowly took shape. It was finally launched in February 1990.

Digital imaging for everyone
This first release was certainly a success, despite the usual slew of bugs. Like the Apple of today, Adobe’s key marketing decision was to present Photoshop as a mass-market, fairly simple tool for anyone to use – rather than most graphics software of the time, which was aimed at specialists.

With Photoshop, you could be achieving the same things on your home desktop Mac that were previously only possible with thousands of dollars of advanced equipment… at least, that was the implicit promise. There was also the matter of pricing. Letraset’s ColorStudio, which had launched shortly before, cost $1,995; Photoshop was less than $1,000.

With development of version 2.0 now underway, Adobe began to expand the coding staff. Mark Hamburg was taken on to add Bézier paths, while other new features included the Pen tool, Duotones, import and rasterisation of Illustrator files, plus, crucially, support for CMYK colour. This was another canny move on Adobe’s part, as it opened up the Photoshop market to print professionals for the first time. The program’s first Product Manager, Steven Guttman, started giving code names to beta versions, a practice which survives to this day. ‘Fast Eddy’ – version 2 – was launched the following year.

Until now Photoshop was still a Mac-only application, but its success warranted a version for the burgeoning Windows graphics market. Porting it was not a trivial task: a whole new team, headed by Bryan Lamkin, was brought in for the PC. Oddly, although there were other significant new features such as 16-bit file support, this iteration was shipped as version 2.5.

Like that difficult third album which can make or break a band, version 3 had to really deliver if it was to corner the market. Fortunately, the team had a whopper of an ace up their sleeve: layers.

By general consensus, the addition of layers has been the single most important aspect of Photoshop development, and probably the feature which finally persuaded many artists to try it. Yet the concept of layers wasn’t unique to Photoshop. HSC – later to become Meta Creations – was concurrently developing Live Picture, an image-editing app including just such a facility. While an excellent program in its own right, Live Picture was vastly overpriced on its launch, leaving Photoshop 3.0 for both Mac and Windows to clean up.

Nothing in later versions quite matched the layers feature for its impact, but there have nonetheless been significant changes. Version 5 introduced colour management and the History palette, with its extra ‘nonlinear history’ behaviour, which certainly opened up whole new creative possibilities. A major update, version 5.5, bundled Adobe’s package ImageReady in an entirely new iteration, giving Photoshop excellent Web-specific features. Layer styles and improved text handling popped up in version 6, and the Healing brush in version 7.

Today and tomorrow
Surprisingly given the age and market leading position of the application, Adobe continues to come up with new features for Photoshop. With Photoshop now part of the rebranded and remarketed Creative Suite 2, Adobe appears to be currently emphasising interoperability through the likes of Bridge.

And the future? Unsurprisingly, Adobe isn’t telling. Photoshop is the jewel in its crown and its development is closely guarded. But there have been hints. Bryan Lamkin, now Senior Vice President of Digital Imaging and Digital Video, speculated earlier this year on a true 64-bit version of the application, and perhaps support for Apple’s CoreImage technology, which would bring enormous speed improvements. Rumours that Illustrator will merge with Photoshop have also abounded for years.

Whatever happens, it’s likely that Thomas Knoll will be involved in some way. Although not directly concerned with Photoshop these days, he still keeps his hand in, recently developing the Adobe Camera Raw plug-in and posting occasionally to the Adobe forums.

His brother still works at ILM too: appropriately enough, he was Visual Effects Supervisor on all three of the new Star Wars films. Without the original Star Wars, there would have been no Photoshop; and with no Photoshop, your job, this magazine and the entire graphics design industry would be very different from how they are today.

Content reproduced from a magazine.

Hari Kumar Balasundaram

After a brief hiatus, The Almanac is back with basics in metering again. This time though we take a peek into the world of digital cameras & DSLR’s & their inbuilt modes for metering the correct exposure for every picture shot.

So what happens when you look through the viewfinder and decide to take a picture, many cameras require you to first press the shutter button halfway down. This allows the camera to properly focus. To capture the shot, typically requires the shutter button to be fully pressed.

Between the time you first press the shutter halfway and the camera takes the shot, your digital camera's brain does the following...

1. Determines what the subject of your shot is
2. Focuses the lens
3. Figures out how much light there is for your subject
4. Calculates the correct combination of shutter speed (how long the shutter will remain open) and F-stop (size of the aperture) to properly expose your photograph

But the most impressive thing is that your camera accomplishes all of these feats in a fraction of a second. In terms of photographic basics, when your camera "meters" the scene, it is calculating the correct shutter speed and F-stop, based on the light at your subject.

The three most common metering modes that are available on most digital cameras are the Matrix Metering Mode, the Centre Weighted Metering Mode, and the Spot Metering Mode. Each of these metering modes have their strengths and weaknesses and the key to making great pictures is understanding those strength and weaknesses because only through understanding them will you know which mode to use in a given shooting situation.

These common metering modes are available on all DSLRs but the way you access these menu items vary from camera to camera so once again dig out the manual that came with your camera and read up on its metering modes and how to access them.

Matrix Metering

Matrix Metering Mode, in this mode the camera divides each scene up into a number of discrete segments, the numbers of discrete segments vary from camera to camera. When set for matrix metering the camera takes separate reflected light readings from each of the zones in the matrix. The camera then selects an exposure setting that is best for the majority of the frame zones sampled. Matrix metering, also known as multi-segment metering or multi-pattern metering, is the best metering mode to use most of the time because it assures you the best overall exposures under most conditions.

Centre-Weighted Average Metering

Centre-weighted average metering gives special emphasis to the centre of the frame, but also covers the surrounding area. Some photographers prefer this metering mode because it’s simpler and more predictable than multi-segment metering, which uses complex algorithms to sort through the data from all the different points of measurement.

Centre-weighted metering is a good mode to select when you want to capture a brightly lit subject and be sure it’s exposed correctly compared with the surrounding areas. This is an excellent compositional technique because people’s eyes are always drawn to the brightest part of a photograph.

Unlike multi-segment / matrix metering, which interprets virtually the entire picture area, centre-weighted metering does not attempt to identify and correct situations like backlighting. This means you have to be a bit more careful when using this type of metering. However, many experienced photographers prefer this mode because they can apply their own exposure compensation (+ and –) and know that the camera hasn’t automatically tried to do likewise.

Spot Metering

Spot metering measures only a small area in the centre of the frame. Typically, this area is a spot that’s only about two or three percent of the entire area of the picture (hence the term “spot” metering). When you have a select area of a picture that you want to precisely meter, and don’t want other areas of the scene to affect your exposure. However, it can be a challenging metering mode to use because you really have to pay attention to exactly what it is measuring and interpret the brightness of the spot yourself. The size of the spot varies from camera to camera, with high-end cameras usually having a smaller spot than entry-level cameras.

Partial metering

Not all cameras have spot-metering mode. For those that don’t, they’ll typically offer a partial-metering mode instead. Partial Metering covers an area exclusively at the centre of the scene, taking up about 10 percent of the total picture area—not quite as small as that of a spot meter. Here, too, if the surrounding area is darker or lighter than the main subject, this mode is a good choice. It will usually give you the correct exposure for your subject, as long as your subject isn’t very light or very dark.

Now that you know what your camera does when metering a subject, May use the light to good use and come back with perfectly exposed photographs.

Until then – Happy Clicking Mavericks!!!

Hari Kumar Balasundaram

[Content sourced from various blogs]

A perfect exposure is the Holy Grail of every photographer. Although there are various methods and ways to understand what correct exposure is all about – The histogram today is one of the most useful ways to understand Exposure in photography.

They are an essential aid for digital SLR photographers striving to achieve consistently correct exposures in-camera and are a more accurate method of assessing exposure than looking at images you've taken on the LCD monitor. Therefore, if you are not already in the habit of regularly reviewing your image' histogram, it is time you did so

In basic terms, a histogram is a two-dimensional graph, often resembling a range of mountain peaks, which represents an image's tonal extent. Whilst, at first glance, histograms might appear quite complex and confusing, they are actually very simple to read. A histogram is a graph counting how many pixels are at each level between black and white.

· Black is on the left. White is on the right.

· The height of the graph at each point depends on how many pixels are that bright.

· Lighter images move the graph to the right. Darker ones move it to the left. Easy!!!

The histogram therefore, quite simply, shows 256 levels of light (tones) that are present in an image. The peaks indicate a large volume of pixels in a particular tone and the troughs appear where there are fewer pixels.

In effect, by simply looking at an image's histogram, a photographer can tell whether the picture is made up of predominantly light, dark or mid-tones.

So what should a histogram look like? This is a tricky one to answer. Despite what some people may say, there is no such thing as the 'perfect histogram'. It simply tells us how a picture is exposed, allowing photographers to decide whether - and how - to adjust exposure settings. However - A few points to note are:

· The vertical scale is of no real consequence (it’s just an indication of the number of pixels at any given light level).

· Low contrast images will have a very narrow histogram, whilst high contrast images will cover more of the graph.

· Techniques such as high dynamic range (HDR) photography (and tone mapping) can be used to increase the light levels captured in the image - effectively increasing the exposure latitude.

· For finer control, individual histograms may be viewed for red, green and blue colour channels or the luminosity.

This is a really great tool to have built into your camera! It lets you get a quick idea of what the exposure was like--whether it was improperly exposed, or whether your scene exceeds the dynamic range of your camera (take a shot from inside your house through a window and you'll run into this problem--too dark inside, too light outside).

The Levels and Curves tools in Photoshop allow you to manipulate your photo's histogram in your image editor. In particular, the Levels tool allows you to stretch your histogram to increase contrast and extend the dynamic range of the photo.

We shall cover the concept of the camera's limited "dynamic range", (the range that it can distinguish between dark and light areas in a frame) & "High Dynamic Range" (HDR) photography, a fun subject for another post.

Until then – Happy clicking!!!

Hari Kumar Balasundaram

How would you like to celebrate your birthday !!! Cut a cake ; go out - party - have some fun rite !!! Well - Chennai calls you this month to celebrate her birthday in panache & style !!!

Yes Folksies - the theme for the month is - CHENNAI ...

the erstwhile 'madrasapattinam' changing lanes to become a slow giant in 'madras' and transcending an all important millenium into a beautiful IT powerhouse yet retaining the old world charm as it is - Our very old Chennai welcomes you to freeze her different facets, her beautiful self in its various forms starting from sunrise until midnight where life does not seem to slow down at all .. Anything about chennai is welcome .. there are no restrictions in the form of shots taken or colour or theme - Simply go out there and shoot and bring chennai back to life in your frozen frame.

However, Pics from the street photography sessions are a strict no-no ... you can shoot wherever you would like and however you would want anytime and post them ..

THEME : Chennai - anything and everything that encompasses chennai ... b&w, colour , whatever format you choose .. just ensure that you choose chennai as the central theme ..

Start Date : 5.08.2009

End Date : 31.08.2009

Posting URL : http://www.flickr.com/groups/ctcstudio/discuss/72157621827147689/

Are u ready People - Lets shoot chennai in all her glory and make the CHENNAI DAY / MADRAS DAY a special one .

cheers

hari kumar balasundaram

"When I saw the photograph of Munkacsi of the black kids running in a wave I couldn't believe such a thing could be caught with the camera. I said damn it, I took my camera and went out into the street." Henri Cartier-Bresson

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Following our first steps into the foray of street photography through a photo walk session in the city of chennai - here's a precursor to what photography in the streets is all about - Read on !!!

Street photography is an approach to photography rather than a location, although the streets are the usual place it happens.

Street photography captures candid mood and situation and it is generally practiced at public places streets, parks, sea-beaches, malls and political and social gatherings. It is pretty easy to take photographs at these places without seeking any permission.

A street photographer can also take the pictures of historical buildings and archaeological monuments.

Street photography can be and often is: Odd things in the fore ground; no central focus; odd crops.It is sometimes referred to as no rules photography.

The plethora of equipment (tripods, lenses, filters, lights etc etc) associated with "serious" photography is left at home, or better still in the camera store. Its just too heavy and bulky to cart around, takes way too long to set up and by the time it is set up the moment is gone.

Street photographers see the usual, the every day with fresh eyes. The reflection in a rain puddle, the colours in a crowd, the balance of a negative space. Their minds are open to all the stimuli that they see and they curse the days when they leave their camera at home.

Street photographers are optimists, for them the glass is always half full. They go out on a photo shoot with no plan in mind secure in the knowledge that this wide world of ours will provide. A subject, a situation, a scene will present itself all they have to have is the presence of mind to capture it when it does.

Street photography is, what all photography is, a snap shot. What shines through is the photographer, his/her interpretation of the scene, what they see in the situation, their reaction to the stimuli, the art they see in their every day walk of life.

Technicians take technically correct and often pretty pictures. Visual artists, whatever their medium, create images that stimulate the mind, the heart and validate the human condition in all its guises. Because, after all, pretty is in the eye of the beholder and consequently very subjective, whereas art speaks to all who are prepared to listen.

content reference : excerpts from bateman's blog & other digital camera resources

Hari Kumar Balasundaram

Our endeavour to present to you - the best of the world of photography continues with a special showcase of one of the most renowned award winning photo journalist of our times - a living legend whose work on and off the camera has helped millions today in the war torn regions from Afghanistan & Europe through Africa.

Reza Deghati (Persian: رضا, born 1952 in Tabriz, Iran ), studied Architecture in the University of Tehran, Reza today is a french citizen , highly regarded and published worldwide by the most prestigious international magazines.

Reza Deghati was a victim and survivor of both the Shah and the Iranian revolution. Since then he has continued to seek out, connect with and document peoples in similar circumstances throughout the world.

Reza returned back to Iran and Afghanistan to help the victims of the bloody war waged between the soviets and later with the taliban. In 1985, Reza Deghati challenged Afghan warlord Ahmad Shah Massoud to a game of chess, and started a friendship that has lasted more than 15 years. "He plays chess like he fights the Taliban," the Iranian-born photographer says, "trying to psychologically defeat you."

National Geographic television has produced several films portraying Reza and his photographic and humanitarian work. One has received an Emmy Academy Award in 2002.

In 1991, Reza and his brother Manoocher founded Webistan Photo Agency^[2], which has been distributing their own archives but also those of several other photographers.

Having been a consultant to the United Nations in Afghanistan in 1990, being culturally close to this country and particularly being a journalist led Reza to found AINA^[3]. The NGO Aina, that is based in Paris, Kabul and Washington D.C., struggles for developing a civil society and cultural expression by empowering media and communication.

In November 2005 Reza was honoured with the title of "Chevalier de l’Ordre du Mérite", the French award for distinguished services in a public or private capacity, by the President of France, Mr. Jacques Chirac.

He also was awarded the prestigious “Missouri Honor Medal for Distinguished Services in Journalism” from the Missouri School of Journalism ^[4], in September 2006, in "recognition of his lifelong contributions, through brilliant photojournalism, to justice and dignity for the world’s citizens".

Commemorating the blogpost of my master crafter & Hero, Some of Reza's greatest pics are on display at my facebook page : http://www.facebook.com/album.php?aid=87077&id=556512363

You could also read more about Reza's Deghati's works from the following websites :

http://photography.nationalgeographic.com/photography/photographers/photographer-reza.html

http://www.webistan.com/bio-reza.htm

http://www.flickr.com/photos/unama/sets/72157618704545386/

http://www.facebook.com/pages/Reza-Deghati/131514225710?v=info

References : wikipedia, webistan, wapedia

Hari Kumar Balasundaram

"I'll just fix it later in Photoshop." - If this is your most used phrase while taking pics – think again!!! Photography is not always about editing and post processing alone – Softwares such as Photoshop have become a very bad prop for good unblemished photography so to speak. You can never completely save an over or under exposed pic using an image manipulation software.

A perfect exposure is the Holy Grail of every photographer. Although, there is no one right way to accomplish perfect exposure, obtaining the right amount of exposure depends on four factors –

• Factor 1: Amount of light incident on the subject

• Factor 2: Amount of light reflected from subject into camera lens

• Factor 3: Amount of light passing through the lens onto the film

• Factor 4: Sensitivity of the film/sensor being exposed (ISO)

Factor 1: is controlled by the intensity of the light source – mostly the Sun on a broad daylight for instance and whether anything is blocking this light – trees, buildings & clouds for example. The position of the Sun at various times of the day vis-a-vis the subject’s position, whether the subject is lit from the front or the back or some of the subject may be in a shadow.

Factor 2: is simply controlled by the reflecting nature of the subject – snow or white coloured clothing for example reflects more light towards the camera than a dark subject such as coal or black stone for example.

Factor 3: is purely controlled by the camera settings – a slower shutter speed or a larger aperture allows more light to fall on the film / sensors

Factor 4: in simple terms is the ISO of the film / sensor.

Whilst taking a look at the four factors – we can easily ascertain that the photographer can control only factors 3 & 4. To simplify – Using an ISO of 100 - let’s say for a broad daylight – the photographer will have to set the shutter speed and the aperture to balance out the effects of factors 1 & 2. How can you best measure the factors 1 & 2 to set the shutter speed & aperture.

The simplest and the easiest way to understand this is to use the automatic settings in your camera – the camera’s inbuilt light meter measures the light incident on the subject [ factor 1] and the amount of light reflecting from the subject [ factor 2] and sets the shutter speed and aperture accordingly.

But here comes the trick question – how can the camera possibly know that the subject its shooting is either snow or a person clad in white clothing or dark clouds in the horizon. To choose the camera’s settings – the light meter in the camera has to make an assumption that the subject is neither too dark nor too bright and that the subject reflects a medium level of light – 18 % reflectance – the midpoint between white n black in the luminance values.

“What the hell” is exactly the thought that would have propped in your mind right now and I know this sounds too techie – but let me explain a bit ..

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What you see there is a nice scene of some fishing boats, with a good tonal range, plenty of colour and some nice late-evening sunlight.

What your camera’s light meter sees is this:

Try this tutorial for yourself: copy the fishing boat scene onto your hard drive. Start up your image editing software and open both pictures. Light meters only see in black and white, so reduce the saturation of the fishing boat shot to zero. Next, add a Gaussian blur set at its maximum level, so that the whole picture is reduced to a field of grey. Use the eyedropper tool to measure the RGB colour value of the resulting tone. You should find that it is a mid-tone grey with an RGB value of around 127,127,127.

It’s an interesting and curious fact that any average scene reflects 18 per cent of the light falling on it. Look out of your window, and unless you live in the Arctic or the Antarctica the scene you see is reflecting exactly the same amount of light as the scene out of my window. That 18 per cent reflection is exactly the same as a mid-tone grey, mid-way between black and white.

Light meters are calibrated with this fact in mind. When your camera takes a light reading, the meter averages the scene and adjusts the exposure to produce that mid-tone grey (or 12 per cent luminance, but that’s another discussion altogether). If you point the camera at a black stage curtain, it will try to make the black into a mid-tone grey, so it will over-expose. If you point it at snow it will try to make the white into grey, so it will under-expose.

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Therefore - Our camera’s light meter whilst shooting a snow covered mountain – would simply adjust to have a medium level of light present as detailed above and therefore snow would appear grey and not snow-white realistically speaking.

Now what if the camera were to focus on the volcano – the rocks would simply be too dark and the camera’s light meter would also adjust here for 18% light and shall render the volcano also as grey and not black as the case may be ..

What if the Sun whose light is reflected by the snow and the volcano is suddenly covered by clouds – although the sun’s intensity has not reduced – the incident light does not reach the snow or the volcano and therefore the reflectance has changed.

In each of these cases – the camera’s exposure setting either is over or underexposed

Now - Imagine if you were to focus the grass incident on the ground with the volcano, the camera would return medium light values as the grass is devoid of such high reflectance as snow or volcano and therefore offers a perfect exposure setting for the shot.

The above setting offers a clue to obtaining a correct exposure – i.e. Under a given lighting condition, meter off a subject of medium brightness to select shutter speed and aperture and then use these same settings to photograph subjects of different reflectivity.

For eg. At a given ISO of 100, if the automatic settings of the camera were to return values of shutter speed of 1/125 at F 22 . But to make the snow whiter – we need to choose either F11, F8 or F5.6 but which one .. By metering on the grass below – the camera now adjusts for the right medium values as F11 at 1/125 secs. By shooting now at F11, we are now telling the camera that it needs more light to shoot a snow covered volcano for a perfect shot i.e ...

Similarly for the volcano – the camera might select F5.6 at 1/125 sec for a grey toned volcano and to make this dark – we would need to reduce the exposure of the sensor. This can easily be done by metering off the grass which would return values of F11 at 1/125 of a sec. If we were to shoot the volcano now – the colour of the volcano would return dark and this would be a perfect exposure.

We have just discovered that be it shooting the snow or the volcano – the correct exposure is F11 at 1/125 of a sec.

With this understanding – do you really think that the reflectivity of the subject has any role to play in the exposure settings. Actually speaking – the reflectivity of the subject is important in one sense that we need to capture the true nature of light incident on the subject when we are shooting.

But the key is we do not want to negate this effect; we want the reflectivity of the subject to directly influence the exposure in order for the subject to look realistic in the photo. The problem is that the camera's automatic exposure system does negate this effect with its assumption that all subjects are of medium reflectivity, resulting in incorrect exposures for all but medium brightness subjects.

To summarize so far, of the four factors affecting exposure, the photographer only has control over the shutter speed and aperture (factor 3), and ISO (factor 4).

Assuming a given film speed, the photographer must choose a shutter speed and aperture based on the amount of light incident on the subject (factor 1) and the reflectivity of the subject (factor 2).

But as seen above, because we want to realistically portray the brightness or darkness of the subject, the reflectivity of the subject should not really affect the choice of shutter speed and aperture.

Thus, the amount of light incident on the subject remains as the primary factor controlling exposure. Therefore - For correct exposure, we must assess this factor and select an appropriate shutter speed and aperture for the photograph.

we shall continue on our understanding of metering and metering systems in the next blog .. Following up on the temples of Cambodia - Here's our stunning pick of the week by Jeff sullivan

Horsetail Falls in Yosemite Valley is selectively backlit by the setting sun. This was an amazing spectacle to witness. Happening only two weeks out of the year, the setting sun falls behind the vertical face of El Capitan, selectively lighting this waterfall with its orange sunset light. Gradually growing in intensity and color for the last 5 minutes or so, it was like seeing a narrow strip of lava flowing down the face of El Capitan. The weather and the water flows often don't cooperate, I was shut out by a blizzard last year, so I was fortunate to see this on two consecutive evenings this year - Jeff Sullivan

Hari Kumar Balasundaram