Picture of the Day, and a brief programming note.

This is largely a test post. I'm dragging myself kicking and screaming into the new era of online communications. If I've done things correctly, both my facebook account and twitter feed should provide some sort of announcement when new material posts to this blog.

That doesn't mean that they will, of course, but they should.

To keep this from being a totally wasted post, you'll find a picture below the fold. It's a recent experiment with an IR filter I picked up a while back.



More like this

How difficult is it to take IR pictures like this? Do you basically just need to slap on a filter, or is there a bit more to it?

There's a little more to it, but not a huge amount. At a minimum, you're going to need a tripod and (most likely) a bulb control for the shutter.

IR filters are basically opaque to visible light. Once you put the filter on, you can't see anything through the camera. This means that it's typically necessary to line up the shot with the camera on a tripod, then attach the filter and take the shot.

A second issue that pops up is exposure length. Most dSLR cameras have an IR-blocking filter over the sensor. This greatly reduces the sensor's sensitivity to IR and requires very long exposure times. (That picture was a 150-second exposure at f/11.) Most dSLRs will only allow you to set exposure lengths of up to 30 sec. Anything longer requires bulb control.

That doesn't seem too bad. I have been using a tripod and shutter remote for taking nighttime pictures, so I think I have the basic technique down.


Why f/11, Mike?

I see no depth of field concern for this image. Or was it because the IR focal point is unpredictably offset from the visible?

By JohnnieCanuck (not verified) on 21 May 2009 #permalink