Quote Originally Posted by Jorge
Or, if you have extra dark slides, cut them up so that they just allow exposure on one side of the film. Bender photographic has a cut up dark slide that allows 2 4x10 exposures on a single 8x10 sheet, so you could use the same idea. Cut one of your dark slides so that the image is 3 1/4x11 and just reverse it for each picture.
I fail to see, at least on my holders and darkslides, how reversing a slide that has a spot cut would accomplish anything unless you were working to separate the vertical aspect. That would make a 3 1/4 by 11 image (roughly). That may work if the slide doesn't have a handle on it so that it could be switched end for end (in the case of dividing the horizontal aspect).

If consistancy of exposure is critical, then a single sheet of film would seem to work the best. If you want to work with different types of film have one holder with color and the other with black and white. Or different films in the same holder. That may be one way to have this work.

If it were me, and I were committed to this course of action, I would gather a piece of appropriate guage tempered aluminum and have it cut to the dimension of a darkslide. I would then have appropriate size openings cut in the aluminum that would allow masking of the film sheet. I would then have the aluminum anodized black to reduce the possibility of flare.

But that seems like an awful lot of effort and expense for the same effect that could be accomplished by shooting two sheets of film (in the case of a black and white-color mixture) or one sheet of film otherwise. I would think that working on this at the print level is the place to do it.

I don't think that an extra holder is that much extra effort at least on that size of format. It may be if I were considering my 12X20 but not my 8X10.
I imagine that 7X11 holders are not any heavier then 8X10. (77 square inches of film versus 80)