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magado
16-12-2007, 11:37 AM
I have major problems with finderscopes.Did see an article in AST some time ago for a simple homemade one. New to this would love help.I have 8"GSO DOB. Merry Xmas To All AT IIS Magado:help:

erick
16-12-2007, 12:00 PM
Hi Magado

Please describe your "major problems"?

Eric :)

rmcpb
16-12-2007, 05:02 PM
What is the problem? Is it alignment or field of view or ?????

magado
16-12-2007, 07:33 PM
Eric I could never the alignment right I did get a rightangle eyepiece to make it easier to no avail. I dont have any finderscope at the moment.I just do without but, i am persistent. magado

wavelandscott
16-12-2007, 09:48 PM
You might consider trying a Telrad (or similar)...I find it to be a useful tool on a Dobsonian mounted reflector and use mine as the finder having removed the original finders that came with both my reflector scopes...

Clear Skies to you...

rmcpb
17-12-2007, 08:55 AM
Did you try setting the alignment up in daylight on a distant tower or tree first?

erick
17-12-2007, 11:04 AM
A GSO 8x50 finderscope, I'm guessing? Is it properly seated in its holder? The rubber O-ring is properly located? The spring-loaded stud properly located in the groove in the finderscope body? Is the problem that you cannot get the object that you have centred in your eyepiece, in the centre of the crosshairs when you adjust the screws on the finderscope? That is the screws hit one end ot other of their travel and you are still not centred? Check that the bolts holding the finderscope mount to the scope body aren't loose and the mount is moving. (The bolts are countersunk philips head screws into the mount with nuts and washers inside the scope tube - you need to remove the finderscope and its dovetail bracket to see them.) I discovered that if you loosen those off (CAREFUL - if you decide to undo them all the way, don't drop a nut on your primary mirror - eeeeek!) then you can adjust that mount to a different position and retighten - maybe the mount has moved. Perhaps the mount needs a little adjustment to align it properly to the scope body and bring the object back into the range of adjustment of the thumbscrew. This is probably only an issue if it is the horizontal adjustment screw that is not reaching the right position at either end, but perhaps also the vertical, but I cannot imaging it unless there is some swarf or shim tilting the mount with respect to the tube.

And, as recommended, this is a job for daylight - looking at a very distant earth-bound object - a TV antenna is great. Just be careful not to point the scope (or finderscope, especially if you take it off) at the Sun.

Let us know how you go? Take a few photos and post them if you still have a problem - maybe we can spot a problem.

Do you know anyone else with the same finderscope? Try theirs on your scope and vice versa?

Eric :)