2 HDR or Not 2 HDR?
You’ve seen them: photos with colors so rich they look like they’ve been dipped in butter. Landscape shots that must have been taken on an alien planet, because the colors in them can’t possibly exist on this one. Objects in these photos sometimes appear to have glowing halos.
Such images are often called HDR, for High Dynamic Range. Remember that “dynamic range” refers to the intensity of the lights, darks, and colors. There are lots of ways to intensify the dynamic range of an image for artistic effect.
And, then, there is another kind of HDR photography, which uses HDR to represent a scene more accurately than normal photography can.
Wait. How can it be more accurate, you ask? Haven’t we all been taught that the camera doesn’t lie? Well, the camera doesn’t lie, but it doesn’t always tell the truth, either.
Your camera is not your eyes. When your camera takes a picture, it uses a single exposure for the whole frame. This means, if you expose for the light areas, you lose detail in the shadows, and if you expose for the shadows, detail in the light places gets washed out.
That’s not the way your eyes work. When you look out toward the sea your eye looks at the sky and adjusts for its brightness and shows you the detail in the clouds. Then you look at the water, and your eye adjusts to the darker tones and you get the detail there, as well. Then your brain assembles the two, and you don’t even notice; you see it as a single scene, with lots of nice light and dark detail everywhere.
In the 1850s, a fellow named Gustave Le Gray found out how to replicate this process in photos he took of seascapes. Mimicking what our eyes and brain do, he would take one photograph of the water, and one of the sky, using the appropriate exposure for each. Then, when printing his negatives, he would combine the two, preserving both light and dark detail. What he discovered was a way to represent, in the crude (but beautiful) photography of the time, what your eyes do unconsciously.
And that’s what this kind of HDR photography does. There are many ways to do it, and one of them is built right into your iPhone’s Camera app.
In your Camera app, tap the Options button, then tap the slider to toggle HDR on. (Don’t forget to tap the Done button.) With HDR on, each time you tap the shutter, your iPhone will take 3 shots, exposing for different levels of light and shadow. Then it combines the shots to produce one picture that preserves both light and dark details.
In General Settings, you can tell your iPhone to save the HDR shot along with the original, unaltered picture …because HDR is not always a good thing.
To HDR or not to HDR — that is the question
HDR is not for all occasions. In some conditions, the HDR setting of your default Camera app results in a flat, washed-out look. And remember, in HDR mode, your iPhone is taking multiple shots and combining them. So, guess what happens in photos in which the subject is moving?
Anna Monette Roberts at GeekSugar.com offers this advice about when to HDR and when not to HDR:
Don’t use it for moving objects, or when the camera is moving. It’ll result in doubled exposures and blurry outlines… and, usually, not in a good way (but sometimes you can get away with it).
Don’t use HDR in bright, sunlit conditions. HDR will flatten out the dynamic range and wash out the colors.
Don’t bother using HDR for a quick series of snaps. Because it takes longer to save the three HDR snaps, a quick series of them just ain’t going to happen.
Use it for close-ups and outdoor portraits. It’ll tend to give you a better range of lights and dark.
Use it in dim lighting without your flash. Your iPhone will try to compensate for dim lighting. The result will be blown-out highlights, and even the dark areas won’t look good, because the picture is a compromise. But the HDR option will combine the best of all three. And you already know what we think about your iPhone’s flash.
You can take this further, as Leana Lofte advises at imore.com. Remember the trick we mentioned in the very first installment of this series? You tap your iPhone to set focus and exposure on light or dark areas of your picture. You can use this with the HDR setting turned on, too. Here’s Leana’s tip: When shooting with the HDR option turned on, tap to expose for the darkest areas in the shot. The HDR algorithm is better at dealing with the bright areas.
You’re not locked into the Camera app that comes with your iPhone. When experimenting with the capabilities of your iPhone and its camera, play the field! Check out the variety of apps available in the App Store for the awesome little camera that’s inside your iPhone. And if you have a favorite HDR app, we’d love to hear from you!
Photos shown here: Gustave Le Gray, Ciel Charge, Mer Mediterranee (Cloudy Sky, Mediterranean Sea). The other photos are the property of the author, and copyrighted in 2013 under Creative Commons. Use ‘em if you need to, but don’t tell lies about ‘em. ~jmr