Yesterday’s Topic: Focus Modes
Welcome to 31+ Days Of Photography Experiments! We are on Day 7. If you need to catch up, we’ll wait here for you while you complete the other experiments.
Tell me, what’s wrong with this picture?
You might say, “Not much (but it is horribly boring).” And you would be right on both accounts. Not much is wrong and it is boring.
But what if I presented this image as it should have been shot with proper metering?
Do you see the difference?
The difference is the first image is okay, but black is not black. This is because your camera is set to believe the world in front of it is not black or white, but neutral gray. Goofy, you might say, but it is true.
The effect this has on photos is, when the area in front of the metering spots (see this post for a refresher on where your camera’s metering spots are) is predominantly black or dark, your camera is set to assume there is something neutral gray there instead. It then tries to match the scene in front of it to neutral gray, making black items not so black. They move toward neutral gray.
What do you do to fix this?
Here’s the experiment you can run:
1) Set you camera on a table and switch it to Aperture Priority mode.
2) Set your ISO to 400 and place a black object in front of your camera, about four feet away. Make sure the black object takes up the central area of the field of view, as in the image above. It can fill the whole screen if you like.
3) Take a photo.
Take a look at your photo and I’m willing to bet it is like the first image. The black object is not really black, but moving toward neutral gray. Now then…
4) Change the Exposure Bias/Exposure Compensation of your camera to -1.3. This is one and one third stops under-exposed.
5) Take another photo.
Done!
Can you see the difference in the two images? Take a look at the histogram for each. The one that is better exposed (hint: the second one) should be pushed more to the left side while the first one is trying to be more even. You don’t want even, you want black to be black!
When To Use This Technique
You will use this technique any time there is a large black or dark area that takes up most of the metering spots of your camera. Otherwise, your camera will make an incorrect exposure. This problem can be eliminated completely by shooting in Manual Mode, at which point your camera will complain you are about to mess up. At that point, you ignore it and shoot any way.
The important part to remember is your camera’s meter, its tool for figuring out which ISO, Aperture and Shutter Speed to use, is not perfect and makes an assumption about the world in front of the camera. When that world does not meet your camera’s assumption, you need to make adjustments. Or shoot in Manual Mode.
If you are ready for it, give “Making White, White” a try as well. It’s the same, but opposite.
Tomorrow’s topic will be Look At The Light.
31+ Days Of Photography Experiments is a series written by professional photographer Peter West Carey on The Carey Adventures.Com. The series is designed to unravel the mysteries of photography so you can take better pictures through practical experiments on the material found in 31+ Days To Better Photography. Subscribe here to receive all the updates and bonus material. Your comments are always welcome.
Thank you so much for the experiments and the orginal posts. They have helped me learn a lot! I just did this exeriment, and like yours, the white background darkened in the 2nd shot. How can I get black to be black and white to be white in the same shot?
The white will darken as the whole exposure is brought down. In the case above, it was too white compared to reality. Beyond that, we would need to make some edits in Lightroom/Aperture/Photoshop to move the white point to bring that white back out. This is essentially what Ansel Adams did when creating the Zone System so that he could balance the tones in the darkroom to match what he saw, because he knew the film would only get him so far.
Your digital camera has a range of 7-9 stop of light capturing ability. Your eye and brain can handle about 14 stops at one point. This is why some editing is still needed. As camera improvements progress, this need will diminish.
Thanks for another great post! But I’m not understanding one point – what should the exposure bias/exposure compensation be set at normally (when you are not taking a photo of a large dark area?). When I took my first photo in Av mode the photo was really dark overall…but then I set the exposure bias to 0 thinking this should be it’s normal setting and then the experiment worked when I compared this shot to the -1.3 exposure bias.
I think the exposure bias was initially set really low and that is why the experiment didn’t work initially. …
Jen,
It does sound like things were out of whack to start with. Check the image on the back of the camera and hit Info or Display until ALL the data comes up on the screen. Some place in there it will show you your exposure bias as: -1 1/3 or -1.3. Check to make sure that first photo wasn’t set to high and try one more time.
It’s important not to move the camera or the light as that can change your camera’s metering.
K thanks…so should it be set at 0 normally (unless of course the image is mostly black)?
Jen, Yes, it normally is on 0.