Jonarsh wrote:Sorry Gary... noob question again!
1) What's a Cassini division??
2) What does Saturn opposition mean..??
Thanks!!!
* Jonarsh *
Hi Jonarsh. No question is considered noob is this forum. No single human being knows everything about everything.
(1) Cassini division is the black "line" you see somewhere in the middle of Saturn's ring. Saturn rings have many rings and they are identified as so-and-so gap/division, Rings A, B, C, D. Check out the amazing photos in this wiki page!
http://en.wikipedia.org/wiki/Rings_of_Saturn
For imaging Saturn, this Cassini division is one of the best feature to use as focusing guide for imaging Saturn. Make the focus as sharp as possible before you shoot.
(2) Saturn Opposition means Sun, Earth, Saturn forming a straight line with Earth in the middle. This means Saturn is closest to Earth which is the best time to observe and image it. Similarly for other planetary oppositions like the recent Mars Opposition:
http://www.astro.sg/2012/02/mars-opposition-2012.html
You can try to experiment using video CCD method (e.g. with a webcam) to capture the moon and planets. They usually generate better results than a stacking a bunch of still photos. Here's a quick tutorial:
http://www.astro.shoregalaxy.com/webcam_astro.htm
This is a nice movie on how to do drift alignment:
http://www.andysshotglass.com/DriftAlignment.html