i wasn't sure where to post this, but:

i just finished making my first hartman mask.  i used a 10" embrordary ring (they're great for DIY astronomy stuff) and some thick, black stock fabric from wal-mart.  i double layered the fabric so light from a bright bulb would not shine through.  then cut 3 1.5" holes 120deg apart about 1.5" from the outside.  it needed a little gorilla tape on the holes to keep the fabric from fraying.

the unfortunate thing is that it's cloudy again, and i won't get a chance to try it out tonight

anyway, i bought enough fabric to make 4 of them and the whole thing cost about $5. 

hope to try it soon

unitl then,

clear skies

Good luck MoFoYa.  Thanks for the tip about the ring.  Keep us posted.

Nice tip MoFoYa, nice and cheap just what I like to hear. I allways like seeing someone come up with something and making it them self and saving a hole lot of money. I made mine out of a found piece of very stiff foam rubber cut some holes and painted it black,,, cost maybe .05 cents for the paint I used.

Al