I just bought a 90mm refractor from an astromarter and have found that it has rather bad astigmatism (it's an Orion f/11). I know it's "caveat emptor" here on the 'Mart and am not complaining - i got a decent mount as part of the deal. My question is this... Is there any way to correct it (I doubt it)? I have verified that the problem lies in the objective and have taken it out and replaced it to see if anything is "pinched" or misaligned (it wasn't). I did see a "K" on the side of the second lens (of the doublet) and two sideways "D"s on the "front" lens, 180 degrees apart. The previous owner had obviously removed the lens set at least once.
Thanks for any help - I suspect that I'm just stuck with an astigmatic 'scope...
Pat
Thanks for any help - I suspect that I'm just stuck with an astigmatic 'scope...
Pat