Thanks again for the comments guys. It has been a fun job and I am really pleased with the result. Didn't take too long (probably 6-8 hours total work, tops) and I got to try out a new tube finishing technique. If I have to refurb another steel tube scope I would use the same technique again. I suspect it is more robust than standard gloss enamel paint and I hope it will assist with thermal issues.
Interesting question about limiting magnification Stargazer. I admit I was probably being a little premature.
In my defence, weak though it may be
, I did find a significant drop off in image quality when stepping from 100X to 150X and I felt this image quality step was greater than could be justified by the seeing. When you combine this with a spherical mirror @ F7.8 and an accepted reasonable limit of 50X/inch for a parabolised mirror, I made an assumption that the 6mm eyepiece was about it.
Gee I like your motorised focuser on the red 4.5" Tasco............wow! At least I think that's what it is. I guess you need that to focus @ 450X
There must have been a factory somewhere in Japan that churned out a zillion of these scopes in the 70's and 80's, both red and white. I do like to look of your red scope Stargazer, the next solid tube scope I do will be metalic deep red with gold trim
.
I suspect that if these scopes had come out with a reasonable dob mount as opposed to the "wobbletronic" they would probably have a better reputation as they do appear to be quite OK as a basic scope. I certainly recall becoming very frustrated with the mount on mine all those years ago.
For a small scope using generic Chinese eyepieces, I was impressed with its performance on the limited DSO work I gave it. Seemed to show quite good contrast with various emission nebulae and open clusters showed a nice dark background between the stars. If the weather is OK I will probably take it to the CAS DSN tomorrow night just for fun just to see what it is like under a dark sky.
BTW, just for fun I have attached an couple of images of the other small CAS scope I refurbished a while ago. This one has been out on almost continuous hire since it went back "on line", I haven't seen it for the last 6 months, I just hope the focuser hasn't fallen to bits yet. Note the signature on the underside of the tube saddle!
Cheers,