More scanning: Best practices for DSLR scanning

Hello all.

Feel free to ignore this, as I'm not sure I'm going to make use of the advice, but I quite possibly might. Also apologies for possible overlap with Frank's DIY drum scanner page, but my ideas are not as ambitious.

Standard wisdom, with some detractors is that using a DSLR to scan in negatives is not a great method. Given that, what would make it better?

I've been toying with some ideas:
1) Using an old Toyo or Omega monorail with one of the DSLR lensboard mounts on the back and I'm not sure what lens on the front. Then hacking another old standard to hold a piece of ANR glass, and attaching that onto an extension rail (I happen to have three...).
2) Wet mounting the negative on the ANR glass
3) Making a sort of light canon with 2 or 3 white paper diffusers so you could fire a flash in one end and have even light coming out the other end with no hotspots.
4) putting the whole assembly in some sort of dark box to eliminate room light.

This seems like it might step the process up a bit. One of the main complaints I hear about camera scanning is that you are at the mercy of dust and scratches, but if you wet mounted the film, I think you might do away with that. If you are scanning a larger negative, uneven light might be a problem, but if you diffused the light, I think you could make an even light source. Not sure if putting the whole rig in a box would be necessary but it might help.

Any thoughts? Waste of time? I'm not really thinking about stitching here, just getting one really good file that takes use of the DSLRs full megapixel file.

Thanks
Paul

Why use anti-Newton (Leibnizian? ;) ) glass when you're wet-mounting? You'll need to use a fairly long lens, such as a 135mm or 150mm enlarging lens, since that setup won't let you get the back of the lens very close to the sensor. Wet-mounting will not do away with dust. Mylar is quite static and attracts dust. Yes, the fluid will help on the side facing the negative, but there's just air on the other side of the mylar, and there will be dust on it.

Since you're not stitching, you might get one of the older bellows units for your camera. My Nikon PB-4 comes complete with a light box and negative holder. Back then the idea was to duplicate slides, but there's no reason why that won't work for digitizing files.

Epson v700

Get a piece of black mat board, cut out the appropriate-sized hole for the film.
Tape the film to the mat board, and behind it place some diffuse material.
Behind that, place your flash; a reflector is all that's needed on the flash head to minimize stray light.

Or use a film scanner, like Vinny says. :)

Keep it simple. Consider the basic requirements. A bellows on a DSLR, an appropriate lens, anything to hold and mask the film, and a diffuse light source are all you need. A T-mount and a piece of plywood can adapt most view cameras to many DSLRs, but a bellows is probably more convenient and certainly saves time. Enlarging lenses serve well as inexpensive macro lenses. They can be mounted on a view camera's lens board or adapted to most bellows with commercially made adaptors. Us cheapskates might use mat board and duct tape. With most setups, a longer focal length than normal will be needed. An old small electronic flash makes a consistant light source. Intensity can be adjusted by varying the distance to the diffuser. The diffuser should be some distance behind the film to avoid recording any small irregularities in it. Opal glass or plastic is ideal. A few layers of ground glass might do. You don't need the complication of glass to hold the film flat. The depth of field at reasonable apertures provides sufficient DOF to mask film curvature.

For some time I have been considering something like this using a Beseler 4x5 glassless negative holder and an Aristo cold light source (it's got a nice diffuser which should be more than enough).

I have a small Holga enlarger which I think it can be converted into a copy stand.

I wouldn't expect to get files with print quality beyond 8x10, but that should be good enough for web and magazine reproduction.

I posted a description of a copy set-up I rigged on my enlarger a while ago, but I can't find it now. The short of it is that I made a lens board for my enlarger that would accept the front of the digital camera lens. Then I expose upward on the film in the negative carrier using the enlarger light source. It works well, but I haven't done much with it.