Thursday, May 20, 2010
Digital Infrared III
In my last post, I mentioned a test to see if your camera is capable of recording infrared images. When you're aiming a remote at your camera, what you want to see is a bright, crisp spot of light, hopefully white in color. If the spot is dim, fuzzy, and red, your camera is still sensitive to infrared, but to a lesser degree, and it may or may not work for infrared photos.
If you can see some light from a remote aimed at your camera, and want to try infrared photography, you'll need an infrared filter. There are many types and strengths available, at widely varying prices. A bit of research turned up recommendations for the Hoya R72 filter, and that's what I bought (about $30.00 on Amazon.com). This is a very dark red, nearly black filter (filters that remove all visible light can run $200 or more). Screw the filter onto your camera (or hold it over the lens of a compact digital camera) and shoot. A tripod or stable surface is helpful, the dark filter adds several stops of exposure, and hand held shots can be blurry as a result. Some blurry shots are still pretty interesting:
Most of the reading I've done suggested shooting in color, at the highest resolution available, and converting to grayscale later (the color shots are pink to deep red in color). Adjusting levels and/or contrast in a photo editing program will bring out the details.
Unfortunately, after buying an infrared filter, it's quite possible that you will not get good results. The biggest issue seems to be a bright spot in the center of the photos you shoot this way. It's apparently due to the way some digital camera lenses are made. I actually bought my infrared filter for my old camera, and found this was the case. Here's an infrared photo shot with that camera. I left it in color, so you can see what the images originally look like.
That bright spot is near impossible to remove, and will ruin your attempts at shooting digital infrared shots. If you're lucky, you won't get that spot, and will be able to shoot good photos.