I'd say hello fellow mirror makers, but I am yet to finish my first mirror. I am fine grinding at the moment.
I am making a 150mm F6 Newt (at least I hope it is an F6). While it was wet, I held a 40mm eyepiece up to it at arms length and tried to focus on the neighbour's roof. I figured that as it was around F6, and a sphere is close to the Raleigh Criteria, I would get a reasonable image off axis if my arms were long enough.
It surprised me that I could focus on a near object holding the objective at arm's length. I could not get it to focus at infiinity, which was a relief, because I don't know how easily i could figure an F4 or F3.
It is also amazing how much light is reflected off glass during the daytime. I am considering leaving it uncoated for use as a drag and drop lunar telescope.
Anyway, I am glad that there are still mirror makers out there and this thread has had some good tips.
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