Monday, July 4, 2011

Finally Out Doing Some Astrophotography

Actually, experimenting with a new product idea, but taking some pictures was part of that.

ASA 400, 1/30th of a second, prime focus, 1414mm f/7.

Saturn is still a struggle, partly because it is a very small target, partly because it is not terribly bright, and partly because I still have not mastered a sharp focus when using eyepiece projection.

The Ring Nebula is at least recognizable (it is the left of center) but this was only a 30 second exposure, ASA 1600, prime focus, 1414mm f/7.  Longer exposures revealed that I am not perfectly aligned on the Celestial North Pole.

I had to overexpose this picture to bring it up, but that makes the black background too light.  Many years ago, I wrote some image enhancement software for a professor at Sonoma State University that would stretch the color range: there were 256 levels per pixel on the pictures that he wanted enhanced, and I wrote some stuff that, for example, let you leave everything below 10 at its current level, but increased brightness of stuff above 10.  It was an effective way to make the blackness of space stay that way, while brightening everything else.  I can't seem to find that in the photo enhancing software that came with my camera or scanner.

1 comment:

Doug said...

Take a look at using the Levels & Curves adjustment if your software has that available. I saved a copy of your image and was able to make a passable improvement using the L&C function in Nikon Capture NX2.