Friday, June 06, 2008

More stuff from yesterday

I've added some pictures of barrel cactus and fishhook pincushion flowers to the web album. I also added a couple more processed pictures.


There have been many times when I've stood looking at a scene and knew that my camera could not possibly come close to capturing what I was seeing. The eye has a much wider dynamic range of operation than a camera, as if each "pixel" seen by your eye was represented by 32 bit word for each color, but the camera only has 8 bit words. In a picture, some areas may be too bright and washed out. For example, instead of seeing the clouds in a picture, the sky will just be solid white. On the other end, instead of seeing what is in a shadow, a picture may just have a black area. You can take a picture that will show the clouds, but everything else will be too dark. You can take a picture to show what's in the shadows, but everything else will be too bright. You can't have both.


Until now. There's something called High Dynamic Range Images (HDRI), which combines pictures made at different exposures so that the entire range of brightness can be in one picture. Well, sort of. One reason cameras don't capture a wide dynamic range is because monitors cannot display a wide range, and you can't print a wide range. So after the software combines images with different exposures, it then has to "compress" the range so it can be displayed. The user can adjust parameters to get the desired effect.


The software I've been trying out is called Photomatix. Since I haven't paid for it, it puts a watermark on the pictures it produces. In some of the pictures I've used it on, I can't decide if I like the originals or the modified pictures. Maybe that's because I'm not very good at modifying them. The first picture on which I tried it seemed impressive. Here's the picture the camera would normally give you:




And here's what I got with the default settings in Photomatix:




If you look at all the pictures in that album (the final result comes from combining data from 3 pictures), you can see that none produced by the camera show near as much as the one from Photomatix.


My results with landscape photography have not been nearly as impressive, but I think that's because the conditions haven't been quite right (or wrong) to make Photomatix useful. As soon as I produce a stunning picture that I couldn't have gotten any other way, I'll buy Photomatix.


When I was up on the ridge yesterday, a couple of lesser nighthawks (aka goatsuckers) kept flying in front of me and then flopping around as if they were injured. They must have been trying to lure me away from their nest (but I never saw it). Anyway, I tried to make a video of their antics. They never flopped around after I got the camera out, though. You can hear their strange monkey-like songs, though. I was about to turn the camera off when I heard coyotes howling. They were loud enough to record, so I kept the camera going. OK, so there are some interesting sounds on the video. You have to turn your PC sound up pretty high, though. I talk quietly a couple of times during the video, but it turns out it's too loud. Sorry about that. Also, there wasn't much wind, but it's kinda loud when you turn the sound up enough to hear the birds and coyotes.


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