Home-made negative scanner

Vic,
Here 2 pictures of the test set-up.
It should be not that difficult to find a second hand Kaiser enlarger

Groeten uit Lanaken

Wim
 
Vic: if you were using a dSLR. my suggestion would have been to find a bellows with slide/filmstrip duplicating attachment (along with the proper adapter for the camera's lens mount), which, together with a small, color-corrected lightbox, would be the shortest (and possibly cheapest) way to make quality dupes without having to buy a scanner.

Unfortunately, yours isn't a dSLR.

You mentioned film scanners being pricey and "slow". Price depends on whose scanner you're buying and how highly-spec'd you want it to be (as well as whether it has to be new or if you're amenable to buying used). Scanning speed depends on a few other things: if you want the absolute-best quality out of a scanner, you'll be working at its maximum resolution, which slows things down (and if the scanner has bells and whistles like Digital ICE, scanning speed takes another big hit). If, however, you have a bunch of slides or negs you just need some small "quickie" scans of for the Web or a PowerPoint piece, most scanners will do the job a lot faster by foregoing stuff like dICE and scanning at a much lower resolution (and scanning in 8-bit instead of 16-bit). And, unlike a home-made setup, most any film scanner will run four mounted slides (or a strip of six frames) in a single run without interruption. Better still, if you find an older Nikon Coolscan with the right optional attachment, you can take a whole stack of slides and have it scan the bunch unattended (the only caveat here is that some of Nikon's bulk-scanning setups worked more reliably than others; the LS-1000 setup I used years ago was generally reliable).

If you had a dSLR, I wouldn't bother bringing up the matter of scanners, but since you just have a fixed-lens digicam (albeit a decent one), I think it's best to check out all viable options.


- Barrett
 
As said, I may have a hard time turning my fixed-lens digicam into a high-speed-medium-resolution film scanner, so I'm still on the look-out for a commercial filmscanner that would suit my requirements.

I bumped into these models: Reflecta ProScan 4000 / Pacific Image PrimeFilm 3650 pro (identical devices?) and Reflecta BatchScan 1800. They are the only scanners (in price range <400 euro) that can take a whole film roll unattended (at least, that's how I understand the specs). Maybe they're not *faster* than other scanners, but they take less of my time, so that's also fitting my requirements.

Any of you having experience with these (or similar) scanners?

Groeten,

VIc
 
Before I got a good scanner I got surprisingly decent (not great) results with a light table and digicam. I left the film in a printfile and flattened them with a sheet of glass. I had to crop down a lot to avoid distortion and light falloff, which reduced the usable resolution. The trick was to find the focal length and focus distance that gave the largest distortion-free area at the center of the image. The next trick was to find the right sharpness and color settings for negatives. The final trick was to make the environment as dark and reflection-free as possible.

I never dealt with the problem of flare from the backlight shining through sprocket holes and between frames, but masking would be the obvious solution.

Not surprisingly, I got the best results with slides.


Now, at the other extreme, this madman decided to bypass the negatives altogether and just use his cheap flatbed scanner as a camera:

[EDIT: the link I had was a temporary mirror. Use this one:
http://scannerphotography.com/
/EDIT]
 
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Vic: I would say the first model (the 4000), being the more recent of the bunch, would be the way to go, although I'm not super-crazy about Pacific Image scanners (yes, all the scanners you mention have the same origin, if I remember right). From a qualitative standpoint, they're still streets ahead of any home-brew solution, and their batch-scanning abilities are hard to match for the money. Just make sure you're covered in terms of both warranty and return policy. If you're buying new, at least you should be covered somehow.


- Barrett
 
My advice is a canon canoscan 4500f. I just bought one for one hundred dollars and it can reproduce images in 3200 by 6400 dpi. The quality is incredible and the price is unbeatable. Not to mention its a lot easier than jeary rigging a digital camera to an enlarger. Plus I can scan four negs at a time. Or if you want to kick it up a notch you could fork over another fifty bucks and by the 8500f that can batch scan twelve negs at a time. At 3200x6400 resolution you get the equivilent to a 20 megapixle pic for a pretty low price tag.
 
I tried the dSLR + enlarger method.
I used a Meopta enlarger to project a 135 BW negative on a sheet of white paper roughly A4 size. I then mounted a tripod just in front of the enlarger pointing down with the smallest possible angle. I used a Canon EOS 300D with a Tamron 28-75/2.8 lens set at 50mm, f/5.6, Av priority, ISO 100, RAW.
I took a blank shoot without negative to get the light fallof. Load everybody in photoshop, invert the blank shoot layer and put it in overlay, adjust opacity, PTLens to correct for distortions, invert, levels, curves, dusts.
I'm rather pleased by the result. I ran the whole roll of 36 exposures in less than 20 minutes through it. It is good enough for web usage which is what I need.

Here are the results :
scan00 : raw output from the camera
scan01 : the best I could have with scanning the negative with my crappy Canon MP730 Photo
scan02 : final output :)
 
Hallo,

thanks for the further feedback! I'm pleased to hear that the enlarger-approach may be a way to go. You chose to use a reflected image, which seems to work and probably is the easiest setup. The only disadvantage seems to be that you can't position the camera perpendicular to the image plane, so you have to correct 'perspective'... it's again a time-consuming image processing step, which probably must be done manually on each image. I can imaginge also the type of paper is of influence. Probably plain office paper is the best? Using any of the fancy 'glossy' paper types may cause too much direct reflection, while you need diffusive reflection for this application...

Since the original post, I've not experimented futher (a.o. due to second child being born), but I'm still going to try to catch a matte screen image (camera behind projection plane), as opposed to the reflected image. As matte screen, I'll be using 'calque' paper (used in printig business as film medium for original drawings/prints to be duplicated on printing plates). (1)

One problem that I already foresee, is that when the setup is perpendicular, the camera will 'see' not only the image on the matte screen, but also see through the matte screen a vage brighter area caused by the enlarger lens brightness... to avoid this, a non-perpendicular setup can be made, so the lens is not in the viewing area of the camera anymore, but then I will also need perspective correction....

You'll hear more as soon as time is on my side.

IN the meanwhile, I've been on the lookout for a specific filmscanner type that allows a complete roll of film to be scanned unattended. Maybe you've got more feedback on that? It's known in different brands:

Mediax WorkScan 3600 pro
Microtek FilmScan 3600
Reflecta ProScan 3600
PrimeFilm 3650 pro


Groeten,

VIc



(1) I've just the other day also used this matte paper very successfully to calibrate the rangefinder accurracy of my Zorki 4. Most info on the web refers to using matte glass plates for checking the image as it would be projected on the film, but the matte paper is easier to setup and also cheaper.
 
lubitel said:
I never tried it but I was thinking if it isnt possible to somehow use a normal flatbed scanner? Leave the scanner top open and have some kind of lamp over the negatives? Has anyone tried something like that?
Click to expand...

I was thinking a bit -- yeah, dangerous, I know :) -- about what might happen if you would take an enlarger (or slide projector) and project the image right on the plane of the scanning surface and scan? Wouldn't this be similar to what those guys do when they use a flatbad scanner as the "film" of a LF camera?
 
dmr said:
I was thinking a bit -- yeah, dangerous, I know :) -- about what might happen if you would take an enlarger (or slide projector) and project the image right on the plane of the scanning surface and scan? Wouldn't this be similar to what those guys do when they use a flatbad scanner as the "film" of a LF camera?
Click to expand...

That won't work as such (as far as I understand optics), because for a flatbed scanner, you need a visible image on the scanning plane. Projection on the scanner glass plate won't create a visible image. If the glass would be a matte screen (you could use the matte paper I mentioned), and the scanner backlight would be disabled, then it might work.

Groeten,

Vic
 
vicmortelmans said:
That won't work as such (as far as I understand optics), because for a flatbed scanner, you need a visible image on the scanning plane. Projection on the scanner glass plate won't create a visible image. If the glass would be a matte screen (you could use the matte paper I mentioned), and the scanner backlight would be disabled, then it might work.
Click to expand...

Here's the logic I was thinking of --- and I'm no optics expert at all.

That bar that slides back and forth on a flatbed scanner is just a light source, which shines upward illuminating the paper being scanned, and a light sensor of some kind which measures the light reflected from the plane of the paper being scanned, in other words the light present at the plane of the image.

Now if you were to replace the light reflected from a paper based image with the light from a projector or enlarger, all nicely focused in the same plane, wouldn't that sliding sensor pick it up?

Ok, what about the light coming from the light in the scanner? With no paper in there, there's nothing to reflect it back to the sensor. Wouldn't it just diffuse out into the space above the scanner?
 
vicmortelmans said:
Hallo,

thanks for the further feedback! I'm pleased to hear that the enlarger-approach may be a way to go. You chose to use a reflected image, which seems to work and probably is the easiest setup. The only disadvantage seems to be that you can't position the camera perpendicular to the image plane, so you have to correct 'perspective'... it's again a time-consuming image processing step, which probably must be done manually on each image. I can imaginge also the type of paper is of influence. Probably plain office paper is the best? Using any of the fancy 'glossy' paper types may cause too much direct reflection, while you need diffusive reflection for this application...
Click to expand...

I didn't move the tripod through the whole roll. I did the process once in photoshop and made it an action, then batch processed it. Even if some auto levels goes wrong, since it's 16 bits, it's not very serious. I used the crop tool + perspective option with a fixed 3:2 final ratio setting.
I used a sheet of A3 260g (by memory) fine-grain Canson drawing paper. Non glossy of course.
 
nksyoon said:
I came across this link for a Photoshop plugin to convert a color neg image to positive:
http://www.c-f-systems.com/Plug-ins.html
Click to expand...

Am I totally missing something here? Is there some trick, some proprietary secret, some undocumented magic to making a color positive out of a good color negative scan?

I'm not trying to be a snot here, but I've sometimes wondered about these payware Photoshop plug-ins for seemingly trivial tasks.

Almost any beginner Photoshop user knows how to compensate for that orange mask (often several ways), invert, and adjust levels.

Yes, I read the link above. What is so wrong with the common ways of scanning and inverting color negatives? Yes, we're all learning more and more about what scanners do and how to make better scans, but is something like this going to *really* do much?
 
dmr said:
That bar that slides back and forth on a flatbed scanner is just a light source, which shines upward illuminating the paper being scanned, and a light sensor of some kind which measures the light reflected from the plane of the paper being scanned, in other words the light present at the plane of the image.

Now if you were to replace the light reflected from a paper based image with the light from a projector or enlarger, all nicely focused in the same plane, wouldn't that sliding sensor pick it up?

Ok, what about the light coming from the light in the scanner? With no paper in there, there's nothing to reflect it back to the sensor. Wouldn't it just diffuse out into the space above the scanner?
Click to expand...

I think you should look at the scanner as a kind of camera. If you take a picture of a dia-projector that is projecting a picture, you won't see the picture, but just the dia-projector.

Even simpler: you should just look at the scanner as being your eye: if you look into the lens of a dia-projector, you'll be blinded by the intensity, but you won't see the image it's projecting!

A camera lens is a device to re-focus light beams originating from one point in the scene into one point on the film. A scanner does the same. So all light beams originating from a point on a paper sheet put on the scanner, will be re-focused on one point on the scanner detector. But if you try to project an image onto the scanner detector, it will just re-focus the light beams originating from the projector lens and create an image of the lens. The projected image won't be reconstructed.

Actually, I don't know if scanners have optics of this kind of all, but it's the only way I can imagine it would work...

Groeten,

VIc
 
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