NOT a Bahtinov Mask

[Ukastronomer]

I have heard that these are perfect for focus on the Moon as that is all I enjoy imaging

Can anyone name it please so I can make one and find youtube video

Many thanks

[Huey]

Jeremy,
Try to search for Scheiner mask. There are different designs. They are easy to make out of cardboard or for a more permanent design use plywood or similar.

Huey

[Ukastronomer]

Many thanks

That led me to hartmann mask :) :)

[xelasnave]

I used one years ago with only two holes and it was reasonably effective.
Alex

[Ukastronomer]

I don't think they are suitable for DSOs etc but for the Moon it is supposed to be perfect, well better than eyesight