2 posts tagged “stars”

PS, I'm thinking of closing down this blog because I've been cheating on you guys with my wordpress blog. If anyone knows a way to export all of my posts from Vox --> WP please fill me in. And while I'm on the subject of leaving Vox, let me just say that the process of submitting posts to groups is ridiculous! I've used vox for over a year and still can't believe the Vox design team hasn't come up with something as simple as checkboxes! Look at Flickr's "organize group" system and how easy it is to use. It takes me more time to submit to select groups than it does to author the post for crying out loud...

Sorry for the rant...

One of the common problems for sky-waters in the winter is dew forming and crystallizing on the optical surfaces of the telescope. Many combat this by using heaters wrapped around sections of the scope called dew zappers. I do not have one, so once the scope begins to frost, I'm forced to pack it up. Coming very close to the dew point, I decided to squeeze in a few photos of the moon with my D200 through the scope.

There are two major hurdles doing lunar and planetary photography with a D-SLR through a scope: Focusing and combating atmospheric seeing conditions. Compared to a nice, bright eyepiece, looking through a DSLR provides a much dimmer, wider field of view that makes it very difficult to perform fine focusing. There are solutions, either using a computer to control exposures and analyze focus as you take multiple photos adjusting the focus each time or by utilizing a live-view if your camera supports it.

Even if "perfect" focus is achieved, a photo may still appear to be blurry due to atmospheric conditions (heat rising, ect). Looking through a scope during "poor to moderate seeing" is like looking through heat-waves (see this 45 second clip of Jupiter for example). The best lunar and planetary images are done by using webcams that are capable of super-fast frame rates of 100+ frames per second. Software goes through hundreds of photos to find the sharp ones.

Even under decent seeing, I'm still having great difficulty focusing without the aide of a computer, a webcam or live-view. I did get a couple sharp ones and they look amazing when viewed at their full 10MP resolution (something you cannot get with a webcam). This is not cropped and gives you an idea of the field of view I get with the setup.

Finally, here is a candid group shot with me at the scope.