Originally Posted by
Kev Williams
My "focus tools" are just pieces of scrap 1/4" thick Cintra or plex.
first do the ramp test Gary mentions. When you find the best focus spot, position the lens head directly over it. Now take some thin cardboard, and cut a piece about 1/4" wide and 2-1/2" long (or 1" if using a cone). Start snipping it shorter until it just fits between the piece you engraved and the lens HOUSING or CONE. Now cut yourself several pieces of scrap plastic the same length and mark them as your 'focus tools'.
I have 3 or 4 at all times because I loose them regularly. :)