Advice Needed: Photo negative scanning.

Factual Questions
1

I have a number of vintage glass plate photographic negatives, up to and including 8" X 10" in size that I want to convert to digital format. I am told that the “industry standard” way of scanning negatives is by use or a rotating drum apparatus, which obviously is not an option for glass plates. OTOH, flat-bed scanners, even with negative “attachments” don’t seem to handle larger than 35mm negatives. The detail in some of these large format negatives is breathtaking and I would like to scan at resolutions approaching state-of-the-art. My sense of the task is that it would best be done by direct scanning of the negatives, not scanning of contact print reflective positives. Once scanned, a good photo manipulation program would be used to burn/dodge/edit as necessary to produce files that would print to exhibition or publication quality. Goals: Quality gallery show/sales, coffee table book, etc., ability to print to 11" X 14" (minimum), 16" X 20" if feasible. and affordable.

I am willing to invest necessary funds to obtain quality tools to do this job. Recommendations please (manufacturer/model/sources) for suitable scanner/printer/programs. TIA

2

How big are your negatives?

3

You probably don’t want to invest in professional scanning equipment to do it, but check out what services are available locally. Some companies (such as output centres) do professional scanning for a reasonable fee.

4

I agree with Urban Ranger. The equipment necessary to scan an 8x10 glass plate and get any kind of reasonable result would probably cost as much as a new house. There ought to be a shop in Baltimore able to scan your negatives for you. Look in your yellow pages under “custom photo lab” or somesuch.

On the other hand, why go digital? You’re right in saying that there is a lot of detail in a large format glass negative. You’ll likely lose most of it in a scan, even if the equipment is “state of the art”. In any case, I shudder to think of how big the file size of an 8x10 negative scan would be. I scan 35mm megatives at 2700 dpi and end up with a 25Mb file. An 8x10 plate has 60 times the surface area of a 35mm negative. at 2700 dpi (not a particularly fine resolution, by the way), that would make a 1.5Gb file. Ouch. Good think RAM is cheap these days.

In any case, if you’re thinking of exhibiting or publishing prints from such negatives, your best bet would probably be to stick with classic darkroom techniques. Again, a professional or custom photo lab would be able to help you out. They can burn/dodge/edit to your specifications.

5

Actually, I DO want to invest in the equipment because:

  1. I want the creative/artistic control over the editing.
  2. I want to avoid the time involved in going to/from a service organization.
  3. I don’t want to entrust one-of-a-kind, fragile negatives to others.
  4. I want the fun/satisfaction of doing it myself. I work for myself VERY cheaply, allowing me a larger budget for the tools.

The scanner must accomodate up to 8" X 10" negatives.

6

OK, either you’re fabulously wealthy or you don’t appreciate the tremendous quantity of money involved in the purchase of a large-format film scanner, if even such a device exists for the scanning of 8x10 glass plates.

Here’s a drum scanner made by Imacon, for sale at B&H’s website. It’s $11,495 (plus shipping) and it only scans up to 5x7 inches.

You may want to contact a museum in your area that has a photo archive and speak to their archivists about your project.

You won’t relenquish any creative control by having someone else create the raw scan file for you.

You’ll have to do the time / money tradeoff calculation yourself. How much time is eleven grand-plus worth to you?

The staff at professional photo labs (i.e. the labs that professional photographers go to) handle one-of-a-kind, fragile negatives all the time. Everybody’s negative is a fragile, one-of-a-kind, precious gem. The lab staff know this and are trained to treat them accordingly. If these plates are truly valuable, perhaps you should contact that museum about taking care of them for you?

I’m hip to that. I do all of my own scanning and photomanipulation with 35mm slides. It’s very satisfying. But when I want a large print to put on my wall, I bring my slide or negative to a pro lab and instruct them on how I want it printed. Sometimes I make a small proof print with my printer to show them what I’m looking for. If I’m not satisfied, the lab will re-print the image until it’s right.

7

Shouldn’t thisdo the job for me? It’s “only” $1,349. I could use some education about the difference between “Optical Resolution” (specified as 1600 x 3200 dpi), and “Interpolated Resolution” (specified as Up to 13,600 x 18,720 dpi.) I grasp the general concept of hardware dpi limitations and software interpolation of those limits but need an appreciation of how the differences “look” on the printed page.

If this scanner (or one similar) gets me into the ballpark, do you have printer recommendations? I suppose anything over 11 x 14 would get into the realm of XY plotters.

8

Oops, apparently the hyperlink failed. I was trying to link to the B&H page showing the Epson Expression 1680 (Professional Firewire Model), 1600x3200 dpi, Letter Size, Flatbed Scanner with Transparency Adapter

9

“Interpolated Resolution” means that the scanner makes up and inserts pixels between those optically scanned. You don’t actually get any more information than the scanner’s optical maximum. If your scanner’s optical maximum is 1200 DPI and you want 2400 DPI, the scanner scans the original at 1200 and then sticks an extra pixel between every scanned one, which is the average of their values. I hope that’s clear: you won’t get any more information off the original by scanning beyond the scanner’s maximum optical (or “hardware”) resolution. You should probably ignore all discussion of interpolated resolution. It’s a con.

There are a lot of variables beyond resolution that will also affect the quality of your scan. A scanner’s dynamic range is roughly its ability to see detail in very bright and very dark areas of an original. That’s related to its bandwidth (24 bit = 8 bits per color (red, green, blue) = 256 shades per color. 30 bit = 10 bits per color = 1024 shades per color, etc.) More bandwidth and dynamic range are obviously better, but different manufacturers make different quality scanners. Other factors are color accuracy, “noise” in the scan sensor, and even connection type and software bundle.

From my limited experience with scanners, I’m guessing that you won’t be able to find a scanner or home printer to truly do justice to a large-format negative plate. There’s just no consumer market for equipment to handle such negatives. You could probably fool around with a flat-bed scanner and a wide inkjet printer (like Epson’s Stylus Photo 2200 which prints up to 13" x 44"), but you’ll probably be disappointed with the results, especially if you compare them to a contact print of your 8x10 plate.

10

I’ve been involved with professional image scanning and editing for reproduction since 1990. There isn’t an effective way of doing this yourself, without building a state-of-the-art photo lab. As you’ve discovered, high-quality scanners are almost all drum mechanisms, and there ain’t no way to wrap a glass neg around a drum. I understand your reasons for wanting to do it yourself, but your desire for ultra-high-quality reproduction without involving an outside service provider is fundamentally incompatible with working from glass negs, particularly at the size you’re talking about.

There’s a couple of problems. One is that flatbed scanners almost all use charge-coupled device (CCD) scanning elements, which do not typically have the dynamic range of the photo-multiplier tubes (PMTs) used in high-end prepress scanners. Another is that, in order to scan a transparent original, you obviously have to have some sort of light source behind the transparency. The low-end desktop scanners like the EPSON you referenced use a translucent sheet (basically a lightbox in the lid over the scan bed) that provides a stationary, diffuse light source. This makes for a much simpler and cheaper mechanism than the point-source illumination units used in higher-end flatbeds with transparency options, like the Imacon *Kamandi pointed out; in those scanners, the illumination provided is much brighter, providing for sharper image capture with additional dynamic range, but the mechanism for moving the illumination source precisely in synch with the scan head is much more expensive. Another problem is that many of the best flatbed transparency scanners use mechanisms for feeding the transparency into the scanner that may not work well with glass negs (I’m thinking of the magnetic frames used in the Imacon units, which have to be sized to the dimensions of the transparency, or the interchangeable trays in the Agfa DuoScan units and others of similar design).

Having said all that, there’s a couple of options open to you. One would be to go ahead and buy a scanner like the Epson above or a used Umax PowerLook III, where you simply slap the tranny down on the glass of the scanner, and see how well you like the results. They may be good enough to satisfy you. They probably wouldn’t pass muster with the photo editors at National Geographic, but ultimately you have to decide what the crossover point on the cost/quality curve is for you.

The other option, and the one that’s more likely to be successful, would be to check with the curatorial staff at a museum or gallery that has a strong collection of early photography, and is likely to have faced these challenges before. Their solution may not ultimately be yours, but at least you may be able to get the benefit of hearing what approaches they considered, what the pros/cons of each were, etc.

Given a damn-the-costs budget and no access to such experts, my approach would probably be to call around until I found a professional photo lab in New York that has dealt with glass negatives successfully before, have them make copy negatives on equivalent-sized film, and then have the negs scanned on one of the desktop drum scanners that are now available; you can get a used Howtek or Colorgetter for between $5K and $10K.

Check around with the folks on Photo.net for more advice.

11

Just for grins, I hit photo.net myself, and found this link on Making Fine Prints in Your Digital Darkroom, which looks like something you should read. I don’t necessarily agree with everything in it (and I only gave it a cursory read) but it’s a detailed description of the sort of thing you’re setting up for (except for the glass neg part – you’re still on your own there).

Other points I meant to make in my first post:
[ul]
[li]Resolution: don’t sweat it. Scanning an 8x10 neg and planning to enlarge it to 16x20 is perfectly feasible at 600-800 dpi, even for the finest reproduction. The reason scanners offer higher resolutions is that often people are starting from smaller originals and needing to scale them up to 3x or 4x the original size. That’s when you need the extra res. Even if some of your originals are 4"x5", a 2400 dpi scan will still give you 16"x10" at 600 dpi. File size is gonna be huge, particularly at 48-bit color depth, but that’s just a little extra money for bigger drives.[/li][li]Dynamic range (Dmax): this is the number you wanna pay attention to in scanner specs. A typical quality flatbed scanner will have a dynamic range in the range of 3.4-3.7 (higher is better). A few really good flatbed CCD scanners get up in the 4.2 range. Most PMT-based drum scanners are at 5.2 or so.[/li][/ul]

12

If your plates are truly vintage, it’s unlikely that they have any color information. If you stick to grayscale scanning, you will retain all the digital info you can possibly get from the originals, but the file sizes will be 1/3 of RGB color.

I can’t think of any good reason to scan these in color unless you just like to use up disk space and CPU time by the globful.

You can always “tint” them digitally later (like sepia, for effect) if you wish by converting back to a color format.

I have some 4x5" glass plates from 1910 in my family. Since I didn’t have a scanner that would handle them, I made simple, photographic contact positives in a darkroom and scanned from those. It worked very well.

13

Jehoshapat. Print the darn things and then scan them however you want!

14

Much obliged to all, thanks for the informative discussion.

15

Add to most of the above good information:

Your biggest problem may be focus.

Some 35 mm scanners have an autofocus feature. This is to help compensate for bowed negatives, variations in the way the strip is inserted, etc.

I don’t know whether any flatbed scanners have this feature. But without it, your photographic image is the thickness of the glass mount away from where the focus is set. I don’t know how much difference this would make, but depending on the scanner, it’s even money it would be noticable.

I’ve recently been scanning some negatives up to 3 x 6 with a 1200 DPI scanner. The quality isn’t fabulous, but the file sizes are. 70 MB, just to get started for a 2 x 2. Once they’ve been placed in Photoshop, add another 20 MB. And we’re not even talking particularly good resolution, here! I’d prefer to be working at 2400 DPI. So the file size for a 2 x 2 would be over 400 MB!

I have 1/2 Gigabytes of memory, and a RAID 0 disk array – which doubles the disk access speed, and processing the 70 MB files still takes a long time.

For a good 3 x 6 scan, you may be talking about a Gigabyte file! Figure on buying a RAID 0 disk (or better), 2 Gigs of RAM, and a dual processor computer.

16

You should always have the emulsion side of the neg closest to the scanner, whether flexible film or glass plate. Then the thickness not only doesn’t matter, the optical properties of the substrate won’t degrade the image, either.

If the resulting scan is reversed or flipped from what you want (left-right), you can easily reverse that in any photo editing program without data loss.

Since the glass is rigid, it should be easier to get a good focus compared to a wavy or warped piece of film.