Need some opinions/help please

[Cam (Cam)]

Hi guys, Ive tried a refractor build with one of those Surplus Shed 127mm f5.5's I've had it outside during the day and focused ( I thought) all the eyepieces on a distant gum tree and I was generally happy with the result. I have now just taken it out under the night sky.I tried the moon first. The best focus I could get of craters ect had no detail because there was so much glow in the eyepiece around the moon looked white. I put in my lowest mag eyepiece a 40mm and aimed at the stars. I couldnt bring them to pin point at all. There were lines shooting out from all of them to one side. I thought this might have meant my objective was out of alignment so tried adjusting that and it didnt help. I have used a metal tube from an old 4 1/2" reflector and used Protostar flocking. Do I need baffles as well??? I thought the flocking was supposed to be enough. If it is has anyone else got any ideas what it may be? Thanks Cam.

[Merlin66 (Ken)]

Cam,
How did you align and collimate your focuser/ objective?
I used a laser collimator in the focuser to hit the middle of a paper screen over the objective...
Then looked at the reflections from the objective (with a end cover in place) when using a bright LED torch into a Cheshire collimator....
http://www.spacealberta.com/equipmen.../collimate.htm

You may also need to fit baffle diaphragms.....

Hope this helps.

[Cam (Cam)]

Thanks Ken. I think I need to collimate my laser collimator. I'll have a look with the cheshire in the meantime. I would like to check the collimation on the tube I cut down for the PST mod too.

[gbeal]

Just guessing here.
Did the lens(es) come as a complete ready to use unit, or did you have to assemble them?
If you had to assemble them is it possible they are not correctly assembled, maybe one element is placed incorrectly?
Gary

[Cam (Cam)]

It came assembled in a cell but I had to remove both lens to machine the cell. I wonder If I did something silly like put it in back to front.

[gbeal]

T'was just a guess Cam, but I have read it many times before, so you won't be alone, if that is what you did.
Maybe take a look, the elements should have alignment marks on them, and perhaps an "arrow" to suggest the orientation. Even simple trial and error might show the correct way.
Good luck,
Gary

[Cam (Cam)]

Thanks for throwing another suggestion in the hat

[2stroke (Jay)]

Have you tried cloudynights, the guys on there are always doing surplus shed objectives.

[Cam (Cam)]

Yes Jay I had a look. It will take me a year to read through all that haha. Thanks