Thread: Focus issues
View Single Post
  #1  
Old 01-10-2013, 06:27 PM
brisen (Brian)
Registered User

brisen is offline
 
Join Date: Aug 2013
Location: Port Macquarie, Australia
Posts: 289
Focus issues

I am having issues with focus on a Celestron 11" HD and the reading I have done suggests that the OTA may not be cool enough. I have attached a couple of pictures of Antares which is the best focus I could get using live view focus on a laptop and prime focus. The second and third pictures are what I think is either side of the 'best focus' I could get. It was taken with a Canon 700 D. Is this thermal currents which are causing the star to look like a blob or is there some other possible cause? The pictures were taken about an hour after the scope was set up.

Any ideas would be greatly appreciated.

Brian
Attached Thumbnails
Click for full-size image (IMG_0028.jpg)
182.8 KB61 views
Click for full-size image (IMG_0029.jpg)
182.0 KB52 views
Attached Files
File Type: pdf Antares.jpg.pdf (74.4 KB, 19 views)

Last edited by brisen; 01-10-2013 at 06:53 PM. Reason: Added a couple of extra photos
Reply With Quote