Amateur Astronomy Sky this Week 2009-10-17

Wow, interesting use of the videos. The goal is to get people interested in astronomy.  I've been kicking around ways to make them useful in other regions and countries. Tough to do though without making them excessively long, complex, and difficult to follow or recording one for each timezone and latitude which is totally not practical.

Language learners are accustomed to watching English language movies with the English subtitles turned on. If you are interested in broadening your exposure, I would suggest a version of the video with English subtitles.

At the very least, I just type a transcript for my students. But when I am ambitious for a class, I often create an *.srt file -- a common subtitle format for videos played on a computer. I haven't done this for any of your videos, but I commonly do it for others.

Cheers!

Youtube default video is very good lately I've noticed. Does seem to improve audio when you switch to hi-rez mode. Thanks for comments and viewing as always!

That sounds like a great combination for visual planetary work.

Gary Garzone took image you referenced. He uses Celestron Nexstar11, F6.3 focal reducer, and 2X barlow, and Celestron NexImage webcam. Thats an F-ratio of 12.6. You can use up to F25 for webcam imaging if atomosphere is steady (rare around here). A webcam is equivallent of 3mm eyepiece as far as field of view is concerned. Nexstar11 is 2800mm so magnification would be around 1100.

Thanks, that's a nice setup.

Just for clarification, NexImage software needs a Goto/tracking mount for its blur/contrast auto-filter? (How much exposure is required to achieve such contrast at such a high magnification?)

As I recall for the NexImage you want to shoot either 10 or 15 frames per sec and set shutter speed between to 1/20 sec to 1/50 sec, and a gain somewhere between 50 to 80% for most bright planets. Tracking mount is necessary for fine focus more than anything. At high magnification its pretty hard to track manually and concentrate on anything else. Planetary imaging could be done without one I suppose but it would very difficult.