Can a scanner be mdified to work with an enlarger?

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I have a besler 23, an elwood 5x7, a Umax Astra 1200s, and a computer with Adobe 5.5. When moving a few years ago, I lost my extra bathroom for the wet side of printing (can still do processing in a daylite tank in kitchen). Is there any way to use a flatbed scanner (in place of photographic paper) and projecting the enlarged negative on it. Seems like you could do any cropping you wished ans still maintain your resolution.

How do you turn off the lite in the scanner, and then turn it back on for standard scanning. Is there a scanner out there for doing this??

-- Beau Schwarz (ejschwarzjr@hotmail.com), May 14, 2001

Answers

>> Subject: Can a scanner be mdified to work with an enlarger?

Maybe :-) The following suggestions violate the warranties of your equipment. Proceed with care.

- Remove the cover and glass from the scanner - Cut the wires powering the lamp, you may wish to connect a switch here if you ever wish to use the scanner as a paper scanner again. - Build a stand around the scanner in order to account for the vibration of the motors in the scanner. - Place the scanner and stand on the enlarger and focus the aerial image from the enlarger upon the CCD sensors of the scanner. - With a good light meter, obtain the output of the scanner lamp at the distance of the scanner glass (in foot/candles or whatever unit you care for) - Figure out how much additional light you will need to generate at the enlarger head in order to provide the scanner CCD with the light it expects. This will vary based on the size of the enlargement you wish to make. As a rule of thumb, you are going to need a _lot_ of additional light, most likely a small carbon-arc lamp of some sort. Keep a fire extinguisher handy :-) - You will need to add cooling capabilities to the enlarger head. At least a high volume fan if the head is metal. A plastic head will just melt. - By the time you get all of the above completed it may be cheaper to just by a used film scanner :-)

Good luck

Mike :-)

-- Mike Kelleghan (mkelleghan@compuserve.com), May 14, 2001.


It won't be that simple. The scanner looks at a white strip under the cover to calibrate, just before each scan. That's the buzzing and fussing around before it starts the scan. If that white strip is too dark, it aborts with an error. So the lamp has to be on for the calibrate, and turned off at just the right time. It will also calibrate in transparency mode. Second, the angle of acceptance: can the scanner lens see the enlarger lens, for the full travel needed? For my scanner, the entrance slit, just below the glass, is about 1/4 inch wide. That might be equivalent to 1/2 to 3/4 inch at the enlarger lens. So you only get a strip scanned, the entrance slit vignettes beyond. So you need a field lens, like a fresnel that covers the scanner glass, but you could see the rings on a fresnel, so a HUGE glass lens. It would be easier to modify the scanner, putting your enlarger lens in it and moving the glass up. But this only gives you a little bit more resolution than the scanner already has: it covers 8 1/2 inch width, and you would magnify your 5 inch side to that.

-- Jim Galvin (jegalvin@lbl.gov), May 14, 2001.

This was suggested ages ago on the Imaging-Resource forum, and caused a bit of an argument about whether it would work or not. To settle the argument, I tried it, and I don't think the idea is worth persuing.
First of all, some translucent material has to be placed on the bed of the scanner, otherwise all you get is an out-of-focus image of the centre of the enlarger lens. Secondly, yes, the scanner software must support turning off the internal lamp.
Even if your scanner supports that function, the results are only ever going to be mediocre, IMHO. It's the translucent material that's the problem. It has to be fine enough so that the texture doesn't ruin the definition, but coarse enough to give an even illumination across the scan. AFAIK no such material exists, hence the conclusion that the idea is a non-starter.
Sorry!

-- Pete Andrews (p.l.andrews@bham.ac.uk), May 15, 2001.

Am I missing something here? Are you wanting to produce a digital print via your scanner? You didn't mention what kind of flatbed scanner you have, but if it has the capability of doing transparencies, you should just scan the negative in at the resolution you need and either convert it to a positive and size it with the scanner software or whatever imageing program you are using. Enlarging onto a scanner bed seems a bit foolish to me but, as I said before, maybe I'm missing something.

-- Eric N. Blevins (eblevins@moh.dcr.state.nc.us), May 15, 2001.

As I understand it, from this and the previous suggestion, the idea is to maximise the resolution of the scanner by enlarging an image onto the platen. The enlarged image could be scanned, instead of a pathetically small original.
I don't think the idea's workable anyway, so forget it.

-- Pete Andrews (p.l.andrews@bham.ac.uk), May 15, 2001.


What if the light from the transparency adapter were used as a light source in the enlarger? I believe it is a CRT. Perhaps it would still be phased with the CCD after traveling though a negative and projected on to some sort of thin translucent material?

-- larry ott (larry.ott@med.ge.com), July 31, 2001.

Did anyone have any luck with this?

-- Joi B (joi@mad.is), August 27, 2001.

Enlarger and digi-camera. See my site: www.arch-pix.dk/opemus/english/

-- Sven Ole Pedersen (sop@image.dk), November 08, 2001.

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