Does anyone know how this is done...by an amateure...a very mechanical amateure?
collimating 7" Meade Mak
Started by earthstar, 05/27/2008 04:26AM
Posted 05/27/2008 04:26AM
Opening Post
Posted 05/27/2008 03:12PM
#1
Meade would insist it's set for life. I've got two of these scopes and have never had a problem with the internal optics, and from what I hear it's not a task for the faint hearted. Even my local experts send these to Meade, but have never had to.
So your problem might be behind the scope. I use a custom scope back called a virtual view, a two inch star diagonal and some efty EPs. All that weight often gets out of alighnment. It's just as anoying to have a diagonal out of collimation as a main mirror, and easier to fix.
Have a look at the diagonal first. Make sure everything's centered up and in straight lines.
Look at the gap between the flat face of the diagonal and the scope-back. It must be the same all the way around the barrel. I had power focuser that was poorly mounted when I bought the first scope, and it had to be reset. I ended up selling it anyway.
I'm repairing an 7" LX50 to sell if you know anyone interested. The optics are great and there's no image shift at all!
8)
Thanks,
Steve
So your problem might be behind the scope. I use a custom scope back called a virtual view, a two inch star diagonal and some efty EPs. All that weight often gets out of alighnment. It's just as anoying to have a diagonal out of collimation as a main mirror, and easier to fix.
Have a look at the diagonal first. Make sure everything's centered up and in straight lines.
Look at the gap between the flat face of the diagonal and the scope-back. It must be the same all the way around the barrel. I had power focuser that was poorly mounted when I bought the first scope, and it had to be reset. I ended up selling it anyway.
I'm repairing an 7" LX50 to sell if you know anyone interested. The optics are great and there's no image shift at all!
8)
Thanks,
Steve
Posted 05/29/2008 09:05PM
#2
Daniel Sinotte said:
Does anyone know how this is done...by an amateure...a very mechanical amateure?
My answer? When it comes to a Gregory MCT like this DON'T. Oh, I suppose I wouldn't mind jackin' the rear cell cover off an ETX RA I paid a song for, but this is a nice scope and deserves TLC by somebody who knows what they are doin' and is equipped to handle the job. Step one? Be darned sure it really is out of collimation.
8)
Uncle Rod
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Posted 05/31/2008 07:43AM
#3
Daniel,
Why do you believe the scope to be out of collimation? How do your stars look?
I had poor images in my scope: with the stock Meade prism diagonal, and with a 2" mirror diagonal when the mirror came loose. (Easy fix)
The scope is excellent after cooling off and when seeing is good. Works best here in the summer when the night is as warm as the day and its hazy and humid.
After 8 years the goto still works but the keypad buttons are worn. I've noticed a lot of ads this year: Wanted Meade LX200 Keypad.
Im very interested in instructions for removing the weight also.
Regards
John
Why do you believe the scope to be out of collimation? How do your stars look?
I had poor images in my scope: with the stock Meade prism diagonal, and with a 2" mirror diagonal when the mirror came loose. (Easy fix)
The scope is excellent after cooling off and when seeing is good. Works best here in the summer when the night is as warm as the day and its hazy and humid.
After 8 years the goto still works but the keypad buttons are worn. I've noticed a lot of ads this year: Wanted Meade LX200 Keypad.
Im very interested in instructions for removing the weight also.
Regards
John
Daniel Sinotte said:
Does anyone know how this is done...by an amateure...a very mechanical amateure?
