View Single Post
  #1  
Old 22-01-2006, 08:24 PM
davidpretorius's Avatar
davidpretorius
lots of eyes on you!

davidpretorius is offline
 
Join Date: Jun 2005
Location: Launceston Tasmania
Posts: 7,381
A lesson for us all - Saturn & Jupiter

Ok, every time i go out there, i am getting better at the basics.

Temperature control:
With the ice packs that come straight out of the freezer and with the two sensors, i can control the difference between mirror and ambient. Last night at most times, the maximum difference was less than .5 degrees

Collimation:
The best it has ever been. The motorized dob means i can keep that star right in the centre of the field of view and then defocus. It is very pleasing to watch that circular pattern stay circular as it goes to a point when focussing.

Focussing:
Hartmann mask and also the moon were around so that using the 5x powermate and the toucam, i can get a good focus, lock the focusser adn then swing to the planet.

Given all this, the jetstream was apparently between 80 and 110 mph, and there was still a twinkle of the stars. The end result is that my jupiter and saturn did not produce the goods. I shot @ 10fps for saturn @ 640 x 480 and for jupiter, i had to go back to 320x240 and boost up the frame rate to 15fps to get enough frames to play with. Saturn was done at 75% gain and jupiter at 1/25 and 100% as that damn fog came in again as i was doing my final alignments of the guidescope.

The moral of the story is that i am always improving these basic techniques so that when that special 2 or 3 times a year perfect night, i am ready!!
Attached Thumbnails
Click for full-size image (final__ST852_WV10_10_58_138.jpg)
41.0 KB43 views
Click for full-size image (final.jpg)
4.9 KB63 views
Reply With Quote