telescope building

I spent today putting my comet sweeper telescope together.  I was very careful to measure each key dimension on the tube beforehand, and make sure everything was in order before installing the optics after dinner.  I ran into just a couple problems.  The used Protostar secondary holder had bent vanes, but sandwiching them between pieces of wood and hammering them, I was able to straighten them out.  Then when I installed them into the tube, I found the vanes were installed at the factory backwards, putting my secondary too high up the tube.  After a lot of thought I figured out I needed to drill new holes 1.5 inches lower down -- and this worked.  The University Optics primary cell was very difficult to install, with its three long bolts.  I wouldn't have used it unless I already had it.  Also it is out of level, so one of the collimation bolts needs to be tightened all the way down -- I may need to get a shorter spring.

I used the old dobsonian base to hold the tube while I ran through all my eyepieces to make sure they come to focus, and they do.  The stars looked a little bit pierced, maybe some coma.  It might be due to my not fully tightening the secondary or having it offset yet; or because the primary was not exactly centered in the tube (something I need to improve).  I ran through all the eyepieces again on the moon, and oh what great views.  So much detail and such a wide expanse.  And even through the moon was giving off a bright halo due to some moisture blowing in from the ocean, the sky around it in the eyepiece was dark dark dark, right up to the sharp edge.  I could see some dimming in the 31mm as the moon approached the field stop, along with a bright blue fringe; the effect was less apparent at higher powers.  I am encouraged by the dark sky -- it should mean the primary is very smooth and gives good contrast.

Tomorrow I will disassemble it and begin working on the mount.  And during this week hopefully start finishing it.  I hope to get it running well enough to take out this coming new moon.