#1  
Old 11-11-2013, 03:26 PM
graham.hobart's Avatar
graham.hobart (Graham stevens)
DeepSkySlacker

graham.hobart is offline
 
Join Date: Nov 2008
Location: hobart, tasmania
Posts: 1,973
positioning of camera with AO8

I am finally going to give my AO 8 with SBIG ST 4000xcm a go as my cooled dslr is not working (see other thread).
My question is this
Currently I achieve focus with three ext. tubes plus feathertouch focuser on my RC 8 with the mono QSI.
If I position the SBIG at roughly the same position would this be presumably at focus point- therefore do you put the sensor there or the front of the AO glass? I mean does the AO 8 matter that it will be ahead of the in focus light cone?
To clarify say the QSI is in focus at 150mm from the RC 8 back plate, should I place the SBIG sensor there to start with or the AO8 glass?
Cheers for any advice- can't really try it as raining but would like to know so I can set up ready.
Graham
Reply With Quote
  #2  
Old 12-11-2013, 05:13 AM
JohnH's Avatar
JohnH
Member # 159

JohnH is offline
 
Join Date: Feb 2005
Location: NSW
Posts: 1,179
The ccd sensor needs to be at the focal plane with the AO8 in front if it. The glass in the AO is flat and alters focus point only very slightly (like a LUM filter does) - iirc it shortens focus a tiny fraction.
Reply With Quote
  #3  
Old 12-11-2013, 09:29 AM
graham.hobart's Avatar
graham.hobart (Graham stevens)
DeepSkySlacker

graham.hobart is offline
 
Join Date: Nov 2008
Location: hobart, tasmania
Posts: 1,973
ao8

cheers mate!
Reply With Quote
Reply

Bookmarks

Thread Tools
Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT +10. The time is now 12:17 PM.

Powered by vBulletin Version 3.8.7 | Copyright ©2000 - 2019, Jelsoft Enterprises Ltd.
Advertisement
Celestron Australia
Advertisement
Bintel
Advertisement
Lunatico Astronomical
Advertisement
OzScopes Authorised Dealer
Advertisement
Meade Australia
Advertisement
SkyWatcher Australia
Advertisement
NexDome Observatories
Advertisement
Astronomy and Electronics Centre
Advertisement