[Wavytone]

Leon this stuff is something else - in most lighting the object sort of vanishes unless you look closely. You can google it yourself, the images are not deceptive.

At some point I’m going to apply it to the inside of the MK91 especially the bits that matter most. Contrary to what many would guess, the inside of the OTA is not the most important place.

One night I pointed the scope at the moon and then took a look inside the top of the OTA to see what areas were most illuminated by scattered light - it was quite edifying. In my case the secondary mirror surround, and the outside of the top of the central baffle tube are most affected; the inside of the OTA not so much as being a Russian mak the tube has baffle rings whereas Celstron/Meades do not.

This would be quite an instructive thing for others to try, too, if you are interested in maximising the background contrast at the eyepiece.

For example in a Newtonian the diagonal assembly and spider arms are critical, as is the are of the OTA immediately opposite the eyepiece which defines the black background behind the diagonal mirror.