Well we've all heard about good companies turning out bad mirrors and it looks like Mom & I got bad luck or taken for a ride when she got this one for me in Xmas 1965. Should OC's founder Dick Nelson be roasting in hell? I don't know, but let all commercial vendors know, little boys grow up and some time, maybe a long time, there is a day of reckoning!
My rehab project has hit a snag because the 4.25" f/10 parabolic primary shows strong astigmatism and undercorrection. The astigmatism is particularly bad, and is symptomatically classic: oval out of focus star images, intra-focus axis at 90 degress to extra-focus axis, it's really awful.
I'm very likely to pop for a new one, they're not expensive, but most f/10s are spherical and OC at least in theory was parabolizing its 4.25s. I'm willing to give an OC 4.25 one more try for authenticity's sake. So if you have a small OC in the closet and would like to cut loose of it to restore the good name of Dick Nelson etc. please do drop me a line. I'm not really interested in the other 4.25s of the era as they were mostly spherical and sphericals are available today cheap. I would be needing a mirror that has at least enough coating to swing a star test as I'm not willing to recoat without checking for gross deformities.
I need the mirror and mirror only, I have a mount and tube.
ps. My other scope is a c14, please don't think I'm starving for aperture!