Exposure Compensation

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When I originally wrote this article, it was just a quick article explaining what I do when I’m shooting white or black cars, but it didn’t go into why I used exposure compensation. The reason was that I saw that I was trying to control the background exposure and keep it from being too dark or too light. I didn’t fully understand why I needed to make these settings, or how much change I needed – I just made the change that I knew would make the photo balance out correctly.

After reading this article, “Why You Need The Zone System for Photography” by Gavin Seim, it all made better sense to me. Previously, whenever I read up on the Zone System, it was written more for film, and people tried to make it sound complicated, so I just dropped it – after all, I was still getting good photos, so why add in the additional complexity?

When shooting car events, you can easily blow out the highlights, or overexpose the sky. Exposure compensation can help you correct this, but how much compensation should you use, and when should you use it? That’s where the Zone System comes in. Whenever you are shooting a photo, the camera has to meter the scene to figure out what middle gray is (think as though your color photo was actually black-and-white), then it sets that to zone 5 (0 is absolute black, and 11 is absolute white, leaving 10 zones that are in-between shades of gray). The problem arises when the object that it thinks is medium gray is actually lighter or darker than medium gray. you can fix this easily when exposure compensation.

Look at what you are shooting, and see if the object (for us, its usually cars), is lighter than medium gray. You can turn you preview screen to B&W if you like to help out. If it is, try to take a guess at how many zones lighter it is. Now, consider each zone the equivalent to a f-stop. If the car is white, and you think that it falls in zone 7 (in relationship to the overall scene), rather than in zone 5, then dial in +2.0 in exposure compensation, and take the shot. then review the histogram to see how it looks.

If I’m shooting in bright sunlight, or have a lot of bright reflections, I drop the exposure compensation down -0.3 or even -0.7. This helps control blown highlights, as it is easier to brighten a dark spot, than to try to recover a blown highlight. The sky tends to be very bright, so you have to get white clouds into zone 9 or 10 usually. Sometimes the scene will have more data than you can get in one shot, so meter for the sky/background for one shot, and then take another where the object (car) is metered correctly, then blend them in post-processing (a tripod and remote shutter release helps here).

If I’m shooting a black car, I find that I often have to drop it down to -0.7 or even -1.0. What this does is get the background more properly exposed with the dark car. What I’m telling the camera with exposure compensation is to consider the car to be zone 4, instead of zone 5.

On white cars, I find that I have to shoot at +0.3 or +0.7. This is also to allow the background to expose closer to the car. You have to be careful not to go to high on this compensation though,or you will blow out the highlights. Again, I’m telling the camera to consider the car to be in zone 6, instead of zone 5.

Make sure that you are shooting in RAW when you start changing exposure compensation, so that you can correct it in post processing if you go too far. Also, make sure that you set it back to 0.0 or -0.3 after each shot, so you don’t forget and accidentally shoot a lot of photos that are improperly exposed.

I highly recommend that you read “Understanding Exposure” by Bryan Peterson. It’s less than $20, and will improve your understanding of exposure and compensation in a matter of hours.

Here is a link to where you can get it : AMAZON