Cool! Does that have a way to use strips of film in addition to slides?
The slide is just sitting over the light source, you could just as easily put down a strip of slides. I don't think a strip of negatives would get scratched, but you could put down a thin strip of mylar or something else as Bill suggested. The knob adjusts the focus.
I use traditional contact prints on 8x10 paper, and doing so has revealed something: I get about one good image per 80 sq inches exposed - so one roll of 35mm film will generally result in one good image. One roll of 120 film - one image, four sheets of 4x5 - one image.
For roll film I always make the contacts with the same exposure and contrast settings. With sheet film, where I am making the contacts one image at a time, I always use the same contrast, but will tweak exposure neg by neg.
Someone mentioned that traditional contacts are too time consuming and costly - the cost is minimal, and once the darkroom is set up, it doesn't take much time to crank out the contacts. If I was less concerned with the image and more concerned with time, I'd shift to an all digital process.
A little hybrid work flow here. I scan the negatives with an Epson V700 scanner, and then import them into Lightroom. The negatives go into Negafile pages, marked with the date and inclusive frame numbers as scanned.
In Lightroom I can then assign key words, so they are catalogued, along with gasp! digital images from my Pentax K 5. The scanned negatives give me a reasonable idea of their sharpness, along with how they MIGHT look if printed in the dark room. I do very little if any post processing in Lightroom.
There are light boxes made for viewing 35mm slides. They hold the slides at a 45o angle allowing the user to sit comfortably at a table for viewing. They typically hold 3 or 4 rows of 10 slides each and so can easily hold 6 exposure strips. They collapse for compact storage. Much more comfortable than leaning over.
A rock pile ceases to be a rock pile the moment a single man contemplates it, bearing within him the image of a cathedral.