A Question About Diagonals

That's very interesting Stevie. I had a (not cheap) diagonal in which the mirror had become unseated from its housing and there was obvious vignetting. Reseating the mirror was straightforward, but I was not aware of the proper collimation procedure you describe. I'm one of those people who does not notice a significant change in the view through 99% reflectivity diagonals versus the 90% versions.

I see that you have a 2" diagonal Paul, which prompts a couple of off-topic comments. Being fundamentally lazy, I hate changing eyepieces and adapters, so I use a 2" like yourself, and either 2" eyepieces or, for the shorted focal lengths, Hyperions which have both 1.25" and 2" sleeves so I never have to swap down to a 1.25" diagonal or use an adapter. Also, I work through the double star targets for a session in order of decreasing separation to minimise the number of time I need to swap eyepieces. How bad is that!

Mike

Hi Mike

It's not necessarily the correct procedure, just one that worked for me. Probably a bit complicated, to be honest.

Here's another way, without having to use a telescope at all.

Excellent, thanks Stevie.

Mike