Spikes are the least of my worries.
Posted 15 July 2020 - 01:20 AM
My 80mm f5 refractor has better contrast, but is not as deep as the 6". So, spikes are not terrible. I don't see them on small stars.
As for a curved spider, if the spread light is anything like the glue I saw, then that would not be acceptable.
Posted 15 July 2020 - 02:07 AM
As a bit of a generalisation spikes come with bright objects, and reflectors are intended to collect light from dim objects so the actual dim object tends to not show spikes. If there is a star in the field then that might.
Would make it not ideal for Jupiter and Saturn and later I expect Mars, but for M1 and I expect M33 they are fine.
So it is a case of pick the target, with at least a little thought and understanding. M45 would have spikes everywhere.
Posted 15 July 2020 - 05:37 PM
Yeah, you will see spikes in a Newt, and rings in a Mak. Very bright objects introduce these problems when a mirror is involved. I got my Mak because my f/5 Newt had the spikes. The Mak is f/12, so it's better for that sort of stuff. Some people use curved spider vanes to help eliminate the spike problem, but I suspect that colimation is a bit touchier. Mark
Posted 16 July 2020 - 01:38 AM
But in focus, I see my vision is not great. I need to fix my glasses. I look forward to viewing through the refractor again. Maybe my eyes focus better through it. They have before.