3.5" Questar Finder Focusing
Posted 13 October 2012 - 08:24 PM
When I switch from finder to scope, the image shifts slightly as well. I can find the target quite quickly when moving the scope up (if I remember correctly). All this makes me think that the finder mirror is slightly off. Does this sound reasonable? If so, does anyone have experience with this issue? Something I can tackle myself or should I send it into Questar for service?
Not a critical issue. Focus is close enough that I'm able to use the focuser with my Brandons. That said, I would much prefer to be able to focus the finder if possible. Any input would be appreciated.
Thanks! Steve S.
Posted 17 October 2012 - 08:32 PM
Thanks! Steve S
Posted 18 October 2012 - 02:59 AM
Posted 18 October 2012 - 12:53 PM
Posted 18 October 2012 - 04:53 PM
Posted 18 October 2012 - 05:57 PM
If it is a regular Questar, It is probably the diopter adjuster on the eyepiece holder that got accidentally screwed in all the way and it is now stuck.
Posted 19 October 2012 - 01:12 PM
The threaded barrel of the Questar's eyepiece holder screws firmly into the control box (red arrow) at the rear of the scope. When firmly seated, the barrel of the eyepiece holder should not rotate (loosen) during focusing.
The threaded barrel of the eyepiece should screw firmly into the top of eyepiece holder (blue arrow). When focusing, the eyepiece should not rotate (loosen) relative to the knurled collar on the eyepiece holder.
With the holder and eyepiece barrels screwed frmly in place, the knurled collar (yellow arrow) and the stainless steel ring of like diameter below it on the eyepiece holder should rotate freely to focus the finder. If the knurled collar is tightly jammed all the way up or all the way down, you probably won't be able to achieve finder focus with your Brandon eyepieces, and you shouldn't attempt to achieve finder focus by unscrewing either the holder barrel from the control box or the eyepiece from the eyepiece holder. The remedy for a jammed focusing collar is to remove the entire eyepiece holder assembly from the control box and free up the knurled collar so it rotates freely through the entire focusing range.
Hope this helps.
Posted 19 October 2012 - 05:09 PM
Thanks! Steve S.
Posted 20 October 2012 - 08:17 PM
Posted 21 October 2012 - 11:55 AM
So nice to be able to focus the finder. I was able to easily locate several clusters that would have been difficult otherwise. Thank you for all you help in figuring this out. ColoHank, I really appreciate the picture. It made it easy for me to see the problem with my scope. It's all working great now and I could not be happier with the Questar.
Thanks again for the feedback. I really appreciate it.