HDR Experiments, Part 3, Cottonwood Lake, Hellyer County Park

On 1/10/10, most of the day was cloudy and overcast. I happened to be in the Evergreen area. Near sunset, I noticed the clouds were breaking up, and I might be able to get some nice sunset pictures. I was close to Hellyer County Park, which has Cottonwood Lake. The lake is one of my favorite spots to take sunset pictures. I wanted to take HDR pictures, but I didn't have my SLR with me, only my Canon Powershot A720 IS compact camera. I didn't have time to rush home and get my SLR, so I thought I'd try taking HDR pictures with my compact.

This will answer the question, "Can you take HDR pictures with a compact camera?" It depends on the camera's capabilities. If it is a very simple point-and-shoot with everything totally automatic and fixed, then the answer is probably no. If the camera allows adjusting the exposure, then it probably can. The key factor is how easily and quickly the exposure can be adjusted. If it has auto-bracketing and burst mode like most SLR's, then there is little difference from using an SLR, and it should be easy. If it has manual adjustments, they likely require pushing some buttons or going through menus. For my camera, I put it into manual mode, select the aperture, and use the cursor wheel to adjust the shutter speed. Since this requires fiddling with the camera, a tripod or some means of stabilizing the camera is almost essential. Fortunately, I had my tripod with me. On my camera, in manual mode, I get a live preview of the exposure on the LCD screen. I varied the shutter speed to make sure I got the highlights and shadows properly exposed, taking a shot every factor of 2 in the speed. Here are some examples. The next 2 pictures below are two of the conventional pictures used for generating the HDR picture above.

This conventional picture was exposed for the sky. Note how most of the foreground and shadow areas are black. This was taken at 1/1500 second at f3.5, ISO 100.

This conventional picture was exposed for the foreground, which makes the sky grossly over-exposed and turns it all white. This was taken at 1/50 second at f3.5, ISO 100.

This is an HDR picture at the same location, but a few minutes later and from a slightly different angle. I used a fixed aperture and varied the shutter speed in order to maintain a constant depth of focus. Whether this is necessary or not depends on a lot of factors, but it is simplest to use a fixed aperture. This was made from 5 pictures with shutter speeds of 1/40 to 1/1002 second at f3.5, ISO 100.

Shooting directly into the sun is one of the hardest shots in photography. The dynamic range is enormous. The sun hitting the lens can cause all kinds of lens flare problems. It drives camera exposure systems crazy. Using conventional photography, most of the time, you get silhouettes or a burned out sky. HDR imaging is one way of dealing with these problems. In this picture, the shutter range was 1/80 to 1/600 second at f3.5, ISO 100. The first few shots I took were straight into the sun when it was higher above the horizon, and the lens flare was severe. Once it had gone down more, as in above, the flare was minor.

This was made from 6 pictures with shutter speeds of 1/40 to 1/1244 second at f3.5, ISO 100. Note how the bottom of the clouds are illuminated with the yellow-orange sunset light, reflected in the lake. Contrast this with the pictures taken earlier and later.

This was made from 7 pictures with shutter speeds of 1/20 to 1/1244 second at f3.5, ISO 100. Note how bright the foreground is. To get this with conventional photography would require a powerful flash or large reflectors.

This was made from 6 pictures with shutter speeds of 1/15 to 1/501 second at f3.5, ISO 100. This shows even more foreground.

As the sun got lower, the exposures got longer. This was made from 6 pictures with shutter speeds of 1/15 to 1/501 second at f3.5, ISO 100. It began to rain briefly, causing the rings in the water.

This was made from 5 pictures with shutter speeds of 1/15 to 1/251 second at f3.5, ISO 100.

After the sun has set, the dynamic range is narrower, but still difficult to capture by conventional photography. The light is a lot lower, so photographing the foreground properly requires long exposures. The use of a tripod or some means of stabilizing the camera is a must to get a proper exposure of the foreground. This was made from 5 pictures with shutter speeds of 1/8 to 1/202 second at f3.5, ISO 100. I could have used a higher ISO setting to be able to use a faster shutter speed, but the noise would have increased. Since I had a tripod, and the objects weren't moving, a slow shutter speed wasn't a problem.

This last picture was made from 6 pictures with shutter speeds of 1/8 to 1/201 second at f3.5, ISO 100. Note how the color of the light hitting the clouds has become redder than the earlier pictures. Not long after this, the sun went farther down, and the clouds were gray. Also, the park closes at sunset, so I had to leave.

These pictures were taken over a short span of time. The first was taken at 4:49 pm. The last was taken at 5:12 pm. This shows the importance of timing, especially with sunset pictures. The window of opportunity for sunset pictures can be very short, so it is important to be in the right place at the right time. It is good to have some places in mind to go to take pictures when it looks like the conditions will be right. Cottonwood Lake is one of those places for me. The lighting at sunset constantly changes, especially if there are moving clouds. For best results, stick around and take lots of pictures over time. Don't just take one and rush off.

One problem with HDR photography is that it has problems when objects move from picture-to-picture. This can happen if there are people, animals, or objects moved by the wind. Fortunately, there were few people and birds around, the wind had died down, and the clouds were not moving fast. Wind causes ghosts in the foreground as trees and grasses move. Fast-moving clouds cause ghosting and multiple images in the sky. That's when a camera with burst mode and auto-bracketing comes in handy, like my SLR. For relatively static subjects like this, the compact camera worked fine.

Note: I have a licensed version of Photomatix, so the pictures don't have watermarks any more.

Pictures by Ronald Horii. Page created 1/21/10, updated 1/28/10

Camera Basics

Choosing a Camera

High Dynamic Range Experiments,

Part 3: Cottonwood Lake, Hellyer County Park