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I dont know what I am doing

Started by shoff535, 07/23/2006 03:03PM
Posted 07/23/2006 03:03PM Opening Post
Well, that really isnt the case (or at least I dont think it is). Here's the situation. I recently acquired a SM40 with t-max and BF-10. I am using this on my TV102.

I would like some help with eye piece recomendations: I tried my TV-20 plossl and it really didnt work very well (low contrast and small FOV); I have an old Celestron SMA 25, and that appeared to work quite well. So, I am considering the Coronado 25mm ep, and or something else (dont know what) that will be lower power and greater FOV, after all, all of Coronado's scopes are 400mm FL, and I'm at 880. I am considering using Focal Reducer which will get me down to ~700mm. Any other thoughts?

I also have a question regarding the T-max: What is it for? I adjusted the thumb screw in/out/mid-way and really couldnt notice any chage.

One curious thing, with the SM40 threaded in securely, and hte adapter installed on the end of the scope, I noticed that if I rotate (unscrew) the SM40 a few degrees, it seems as my visual image goes blank. why would this be? does the SM40 work as an interferance filter (how would it do that without double stacking?