You remember the blog about 18% gray right? That’s the one about camera meters and how they are calibrated to produce 18% (middle) gray with every exposure.
Ok, if you never did any shooting in the “old days,” of photography with film, then you may not have a clue what I’m talking about. Today, instead of talking about 18% middle gray, we talk about understanding the white balance setting in our digital cameras. The default WB setting used is the Auto mode. In this mode, the camera will auto adjust for any color hue that is introduced into the photo. It may not always work, but it’s a good “fire-and-forget” mode.
Which works well as long as there is a good balance of tones from light to dark. However with animal photography we often don’t care about all the tonal values, we only care about correctly recording the color (tonal value) of the animal.
So if you’re a more advanced user, you should consider doing the WB calibration manually. Here’s what I typically do. I hold up a piece of thick white paper and point the camera at it. This allows the camera to know what “white” really is, then I base the WB settings against that. Whenever I do this, I find I hardly run into any coloration issues in my final pictures. Try it and see how it works for you. (Don’t forget you have to manually set your exposure based on the reading you get with this technique.)
That’s why I still like to think of balancing the exposure with a gray card. Because there are lots of things outside that are gray. Driveways, tree bark, just look around and you will find something middle gray to use. So you point your meter at something that is about 18% gray, take a reading, and use that exposure to base your settings on.
If you are new to this animal photography thing you are probably more familiar with photographing scenic images, and when you go for a very light or very dark animal subject your meter seems to be on vacation.
Take a snow photograph. Even though snow is white and bright, your exposures come out looking gray and flat.
What happened? Well the 18% rule of exposure happened.
When you are photographing something very bright (snow or a beach), the meter, which is calibrated to produce 18% gray, reads all the light and says, “Yikes! This scene is too bright! I need to shut out some of this light to achieve 18% (middle) gray.”
So when the computer in your camera adjusts the exposure to achieve an 18% (middle) gray reading, the snow which is bright white, comes out gray white in the final image. Don’t blame the meter…it’s just doing what it is calibrated to do.
Ok, we got it. So what to do?
Well first of all, you need a camera with manual exposure settings so you can go into the menu and set the exposure yourself. No reliance on the camera computer for you! Your good and you know how to manually set your meter.
Quick review. Exposure is determined by three factors working together; shutter speed, aperture and ISO. For the purpose of this blog, let’s forget about the ISO because it’s not going to be a factor for understanding this concept.
We are making animal images, so our first step is to put the shutter speed on 250th of a second. (We always shoot animals at a speed of at least 250th of a second because we know we need to stop the action of their movement to get a sharp image.) Next, we OPEN UP the aperture one stop.
What? Open up the aperture? That’s crazy…that’s going to give the scene even more light which means the snow will get even more exposure.
That’s right. The snow will get more exposure, so that it will be rendered in the file as bright white and not gray white.
So enough with this snow stuff. We’re animal photographers and most of us aren’t photographing polar bears in the Arctic, even if we’d like to be photographing polar bears.
How about something wild, but a lot easier to photograph?
Take this gosling. In the first image, I set my shutter speed on 250th of a second, and let the camera computer choose the aperture setting.
The gosling’s color is rendered too dark on the file.
Next, using the same shutter speed, I opened up the aperture two stops, which rendered the gosling the correct color.
Cool. The gosling’s feathers are now a true white color.
Which means that if I’m hangin’ out with a photographer from National Geographic, and I show them this image, they’ll know that I know my stuff. Who knows? I might get an invitation to go on that next big photo shoot on the Arctic ice.
Once you understand that to achieve correct exposure of a white subject, you need to open up your aperture, you can run some tests on your white animals opening up from one to three stops to find the sweet spot that works best for your image. Write it down. Next time you’ll have your notes to refer to and you won’t have to fiddle with your settings.
Now for the quiz. What do we do to correctly expose a black subject?
If you understand the concept, it won’t take you long to figure this one out, but stay tuned. You can check out the answer in my book, or wait for the next blog roll.