More About Lighting

Tuesday, December 13, 2011

More About Lighting

(Why some parts of your photo may be too dark or too light)

     I'm sure that you've taken a photograph only to find out that parts are too dark and too light. In both cases, you cannot see the detail. The reason for this has to do with how a photograph is "captured". The same problem occurred with film as it still does with the CCD's of a digital camera. The difference is that now we have image-editing programs to try and "remedy" the problem.

      A photograph is a "capture" of light reflecting off the subject in different amounts. In a totally dark room you wouldn't be able to "capture" anything. And if you set your camera incorrectly on a snowy  day in an open snow-covered field, you'd only get a big whiteout, again with no detail.

     Now let's say your camera is working and you photograph a set of pool ball on a pool table. Some of the colour reflect more than others. So the White and yellow balls will be too bright (they reflect alot of light) and the black ball will be too dark (it absorbs a lot of light). THe rest of the coloured-balls may underexpose or overexpose depending upon how much light they reflect or absorb.

     The beautiful Tootsietoy car hauler arrived today, and while I was photographing it for listing on E-Bay, I got the idea for this instalment. While there are only 3 cars,  they will illustrate the "problem" of lighting them, but just as easily, when I  tell you what I did, you'll understand the nature of light better.

 The photo above illustrates how different-coloured cars reflect or absorb ;light differently.

Please excuse the fact that this photo was not photographed at the same angle as the individual cars below, however, the nature of the "problem" remains the same.

I moved the trailer each time so that each of the 3 cars would be framed in the exact same position in front of the camera.

Looking at the cars, we can say this:

1. The silver car reflects the most light and absorbs the least.

2.The blue car reflects less and absorbs more than the silver car.

3. THe dark green car reflects the least light, and absorbs the most.

When you take a photo, the "correct exposure" is  for you to be able to see "detail in the bright areas" called "highlights". 

 The "highlight area" in parts of the silver car are losing detail.

The photographic term for this is "washed out" or "loss of detail in the highlights". 

 What I did here was to underexpose this car by 1/2 f-stop.

Less exposure meant less reflection, and hence the detail is "better" but not 100%!

 The blue car exposed well from the initial exposure.

I didn;t have to change exposures to get more detail in the highlight or less detail in the shadows.

 The dark green car "appears OK". 

However it is underexposed as the true colour actually is lighter.

What happened? This  dark green car absorbed more light than the silver or the blue car.

We could correspondingly say also that it reflected less than the silver or blue car.

 For this car, I gave 1/2 f-stop more exposure in order to lighten it up.

This colour or tone is much "truer" to the real car.

      So what's top be learned from this, or better still, how can we "remedy" these problems? 

The best solution is to do everything in the studio, or whenever and wherever you are taking the photo.

Why not simply Photoshop it? The answer is to learn good picture-taking habits, and not rely on the post-process. Why? Because, you'll learn to take better photos, and you cannot always rely on Photoshop to solve the problem. And once you you shoot, there's no going back if you can't correct the image in the computer! Also, it takes more time to post-process your image. If you operate a studio, you are charging so much for each image. However, if you have 100 toy photos to photograph, and you "play around" with them in Photoshop, then you'll expend more time. More time means less money in the end, and time is money!

 So how would you solve the problem in the studio?

1. Angle the light so that more light falls on the green car and less on the silver car. 

2. Add more light either through another light or with reflectors.

3. Take away light by blocking light to the silver car. How? With a light blocker. The photographic term for a light blocker in the studio is "gobo", which is short for go between. In this case, the "go between" is the light and the subject.