NavList:

Interesting notes on your side error methodology.  I was unaware differences in mirror face might have an effect. My initial reading led me to the cylinder method.  Celestaire used to have them in the catalog, but I think they disappeared.  I wonder if this is why.

Having a simple modelmakers mini-lathe, I had an attack of insanity and made a set for myself out of brass rod stock, which mic'd up within .001 of identical. (I keep them wrappedseperately in a super soft cloth, as dropping them or even banging them together would create havoc.  I used these for initial setup.

I noticed last week when I was checking index correction with the sun, I had the shades patterned to make the images the actual/reflected different colors. I noticed a bit of side error on the superpositon of the sun.

This weekend's task on the dock, I will use cylinders first, then use the sun & stars to compare.  I would like to see if my setup was wrong, or if auto travel etc. are responsible for the new/old? side error.

I concur on the gut instinct part. The setup just felt a little off on my last two rounds of lunars. turns out the later sun check proved the "feel".

P.S. can somebody please tell the full moon to come out in the daytime this weekend, I want to try out my new higher magnification prism scope on my lunar sun sights