PDA

View Full Version : transparency adaptor/lightsource for 5x7 on flatbed scanner?



Jason Greenberg Motamedi
28-Feb-2002, 16:21
I have recently switched from 4x5 to 5x7, and have run into a bit of an impasse. I like to scan all of my negatives/chromes for cataloging and rudimentary printing, however the transparency adaptor on my flatbed scanner is not large enough to scan the full 5x7.

I am reluctant to purchase a new scanner, especially since the commercially available ones have transparency adaptors no larger than 4x5 inches, and would have to spend significantly more on a 5x7. I thought that if I could find the correct sort of light source I could simply place it on top of the scanner, sandwiching the 5x7 between the light source and the scanner?s glass. I notice that Calumet offers something of the sort for 4x5s for about $70.

Does anybody know what the correct type of light source is? I have tried normal fluorescents (flipping my light box over on top of the scanner), and have had poor results--the scanner picks up the ?flashing? or 'banding' which is invisible to our eyes. Using regular incandescent bulbs, even with diffusion, results in a nasty hot spot and weird color balance problems. Any other suggestions?

dan nguyen
28-Feb-2002, 16:48
since "for cataloging and rudimentary printing"...

did you try to scan the 5x7 twice and patch them together in photoshop... ie..1st scan 1st half - 2nd scan 2nd half... then match them together in photoshop...

David A. Goldfarb
28-Feb-2002, 17:10
Not an answer, but an alternative--Do you have a digital camera? For basic scans, mostly for web use, I've been digitizing medium and large-format B&W negs and color transparencies using a Nikon Coolpix 990 and a 5000K lightbox on a copy stand. The results aren't too bad, and I get up to a 13MB TIFF that way. That's half what I get from my 35mm film scanner, but I have somewhat more real control over exposure with the camera than I do with the scanner.

Henry Ambrose
28-Feb-2002, 19:45
You've gotten a couple of good answers so far.

The reason that you see the banding is because of the frequency of your light source. It flickers at a rate that you don't see but the scanner does. Its sorta like photographing a TV at a shutter speed that picks up the scan lines going across the screen. You might solve this by replacing the power supply in the light box with a high frequency one. I say 'might' because I have no idea of the construction of your lightbox. Or you could buy a light that would work. I think Aristo makes light sources that give daylight rendering and have high frequency power supllies.

I suggest you consider buying a new scanner with a full 8X10 transparency lid. The Epson 1650 comes to mind as a good choice. With lid its under $500 I believe. This will give you lots of resolution and a surprisingly good scan and the possibility of an excellent small print. OTOH, for similar money, a digital camera will work great for identification and cataloging and you might find it useful for other things as well.

Jim Roof
28-Feb-2002, 23:42
You might try looking for a used HP IIIC scanner or another one of the H series. But, before you buy one, get a hold of a used transparency adapter for it. It illuminates a 8.5 x 11 area. I used to have one but sold it on Ebay over 18 months ago when I got my Agfa T2500 Duoscan.

If you are looking for a new scanner you might check out the new Epson line. I understand that they have a flatbed w/transparency adapter that runs about 1200.00 and is supposed to do about 3.5 dmax. I got a brochure for it some months back and the images on it were beautiful and all scanned from chromes on their new scanner.

If you can find a used T2500 Duoscan and can afford it, get it. I can scan four 4x5's at once to make proof sheets and the scans look great... very close to what I see from the same chromes drum scanned.

Jim Roof
28-Feb-2002, 23:44
Here's what I am talking about in the previous post.

http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=2005210301

Jim Galli
1-Mar-2002, 00:50
Jason, This is way out there but it'll cost you what it's worth. A friend of mine who has to build everything himself made a light box out of that white soft rubbery plastic butcher block cutting board stuff. I have to admit the light comes through that thing in an unusual glowy sort of way. I wonder if it would absorb the light box flicker? They seem to be about 5/16ths inch thick. Made to lay on your drainboard for cutting meat on. Good luck. Jim

Pete Andrews
1-Mar-2002, 07:52
Mustek used to make a light lid called a 'Transparency Adapter IV'. It has an illuminated area of about 6" x 8", and is perfectly even in illumination. The light source consists of two high-frequency xenon tubes, which give a nice warm-daylight balanced light. It comes complete with its own mains adapter.

I'm not sure that Mustek make it any longer, but they may make something similar. In any case, I'm sure that there's still some stock of these adapters out there, somewhere. It's still listed on Mustek's German, Italian and Russian websites.Failing that, have you looked at these little battery operated light-boxes you can get nowadays? I believe that they use high frequency xenon tubes too.

Wes_2428
1-Mar-2002, 09:52
I have an Acer Scan Prisa 1240UT that will scan up to 5x7 trans. It was only around $150.00 new and since it is over a year old, you might be able to find a used one cheap. It has a plastic cover in the lid you pop off and then use whatever mask, which is included, that you need. I ordered mine directly from Acer. You might want to check out their, as well as other manufacturer's web sites, to see just what is available.

Wayne Crider
1-Mar-2002, 15:19
Just a thought; Would another cheap used scanner flipped upside down work? You could disconnect the belts if need be. I'm not sure of the light source tho. You'd have to check that out.

Phil Brammer
5-Mar-2002, 10:47
Try and find a Mitsubishi DV 648UT, it does A4 size (210mmx297mm) trannies to 1200 dpi optical, fine for cataloging and small prints. I puchased mine new here in Australia for AU$ 240 (approx $120US)

QT Luong
5-Mar-2002, 18:15
Indeed for dirt cheap 5x7 scanning, the Acer cannot be beat. With photoshop and some time on your hands, you can even get decent results. I picked up a 620UT (only 600dpi) for $30 at office max and made a 13x19 that most people cannot distinguish from the 13x19 printed using the Tango scan.

Jason Greenberg Motamedi
7-Mar-2002, 00:51
Thank you all for the help. After considering all the options, I bought a cheap Acer 1240UT Scanner, hopefully this will resolve the issue. Before doing this I borrowed a friends 'thin' transparency viewer, a Cabin, which I tried with my scanner, flipping it on top of the chrome. It appeared to work, although it was too bright. Anyway, it cost more than the scanner. I also checked out the Epson scanners, these don't appear to have large enough transparency adaptors, only 4x5 or smaller. Of course, I would love a Agfa T2500... however I am a college teacher, not a graphics professional, and the cost of the Agfa far more than I can rationalize. Using a digital camera is an interesting idea, however my camera, a two year old Canon, is really terrible with macro shots (I should have bought the Nikon!) I have used it occasionally for archival research, where they won?t allow photocopying, it is not the best solution, but it is usally legible, however this isn?t good enough for pictures, and I can?t really see myself buying a new one.

Thanks again.