I received a question from Ricki, who makes really cool fabric banners, pennants and flags, and also writes a blog about plants and flowers and such. She uses a Panasonic DMC-TZ1 camera, and often has a problem with loss of detail on photos of white flowers. Here’s an example:
An here’s the corresponding histogram (click here if you need a refresher about histograms):
I can certainly see Ricki’s concern. The white flowers sure do lack detail, and the histogram illustrates the selective overexposure (the high vertical bar on the far right). No amount of post-processing is going to recover that lost detail.
So what went wrong? Well, it looks like an unfortunate combination of a few things:
- That scene has a lot of contrast, with the bright white flowers set against the shadowed green background. If we were to look at that scene with our eyes, we wouldn’t have any trouble seeing detail in both the flower and the background. That’s because our sense of sight has a very high “dynamic range.” In other words, we do a pretty good job of resolving both bright and dark portions of our field of view at the same time. Digital cameras, in short, do not. So when we come across scenes like this, we need to change our expectations and compromise a little bit. We need to accept that we’re not going to get the same image out of the camera that we can see with our eyes. But what we can do is make sure that the important parts of the image are properly exposed.
- The Panasonic DMC-TZ1 is a pretty darn good camera overall, but one of its known weaknesses is its inability to handle high-contrast scenes like this one. How’s that for bad luck?
- The camera’s metering mode was set to “multiple.” That means that when it was judging what kind of aperture and shutter speed to use to get an acceptable image, it considered the entire field of view. Since that field of view was mostly green and brown background, that part of the image got a lot more weight in the camera’s analysis. The exposure was pretty good for the background, not so good for the flowers.
- The camera’s exposure compensation was set to +0.66. That means that after all the metering was done, the camera boosted the exposure even more.
- And last, but certainly not least, the flash fired. It’s hard to tell from the image what the lighting conditions were like at the time this was shot. Regardless, using a flash in this situation is nearly always a bad idea.
Now that we know what went wrong, what can we do to fix it? I took a few mid-morning test shots (I don’t usually like to shoot in direct sun unless there’s a special effect I’m going for, but I did so in this case to illustrate a point). Although the sun wasn’t up at mid-day height, it was certainly high enough to brightly illuminate some white petunias that my wife planted. I put my camera in “spot metering” mode, aimed the camera into some green shadowy areas, let the camera figure out an exposure, recomposed and got this shot:
Can you see how nicely exposed the green area is? Great, but Ricki wants to show detail in the flower, not the greens. So this time I metered on one of the white petals, and this was my result:
Well, that’s a little better. But I still don’t like it quite as much as one I took in the evening about an hour before sunset. It’s the same flower pot, but on the opposite (west) side. The evening sun, although still evident, was lower in the sky than during my morning shoot, and was therefore more subdued and softer. I didn’t even use any special metering. I just put my camera in “matrix” metering mode (similar to Panasonic’s “multiple” mode), composed and shot. Here’s the result:
I think that’s a keeper!
So, what did we learn about shooting white flowers (or any white objects)? In summary:
- Evaluate the scene and decide what’s important.
- Learn a little more about your camera. In this case, spot metering might be useful (page 75 of the DMC-TZ1 user manual). Meter on the part of the scene that you care about.
- Don’t use a flash unless you’re absolutely sure about what it’s going to do for your shot.
- Consider the quality of the lighting. It’s much easier to get better photos when the sun is lower on the horizon and not so bright. The contrast of the scene will be lower, the detail will show more clearly and the colors of the entire composition will be more pleasing. More predictable still would be shooting when the sky is overcast (I discuss that in detail here).
Keep those questions coming, and until next time … Happy Shooting!