i just discovered this and thought i'd mention in case anyone else wanted to try it. according to this thread(in chinese with pictures):
http://lomotw.com/phpBB2/viewtopic.php?t=5351 you can use a black transparency that art supply stores sell to mod the sx-70. i tried it, but the shop i went to didn't have black so i ended up with brown. my mixed results are below. needs to be a bit darker, and the colours are a bit wacked, probably more because of the brown than anything else. but at least the film's not blank!
william
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