Thoughts on Theory and Practice of Scanning (Archival/Forensic)

<p>I've been working on the problem of archiving scientific (and forensic) images for a long time. I've completed (several times) the digitizing of a huge archive of professional and personal images. Being in a philosophical mood, and feeling a little "apotheosized", I thought I'd lay down some commandments for anyone who is interested.<br>

If you're not interested, why are you still reading this?</p>

<p>Like several better known systems of ethical rules, the first commandment<br /> is<br>

<strong>I. Do no harm.</strong><br>

Always keep the original slide/image. If the pessimists are right, and digital is ephemeral, then the original may have survived well enough to be re-scanned. If the realists are right and entropy will engulf everything, it couldn't hurt.</p>

<p><strong>II. Copy the image.</strong><br>

What you want for archival work is to reproduce the surviving image as close to the real, existing slide as you can. If the film is magenta-hued, the archival copy should be also. If it’s grainy, so also, etc. You are, of course allowed to do <strong><em>non-intrusive</em></strong> cleaning of any dust on the image.<br /><br /><br>

Turn off as much of the “dust reduction” and the like as you can in your copying workflow. At the best, dust reduction will be neutral, but at its worst, you are achieving “dust free” by blurring the image. Dust cleaning can be done automatically or manually later to copies, not to the "archival" image from the scanner.<br /><br />Ditto for color correction and other such processes. <br /><br /><br>

This is, of course, in reference to evidential images. If you are scanning images of the family puppy (Hi, Begheera), turn on all the automatic crap you can find if you can stand the results.</p>

<p><strong>III. Scan once, scan high.</strong><br>

The reason I have "completed" my scans more than once, is because I tried to save time and effort by making only small copies of the originals. <strong><br /></strong><br>

If the images are archival, START by scanning as high resolution and quality as you can. It will save time in the long run, believe me.</p>

<p><strong>Subtotal</strong><br>

I emphasize that I'm talking about evidential imagery, not your personal snapshots. The problem I'm addressing is that of people not approaching digitization of older images in a systematic way, mixing up different levels of the work flow. The key here is to keep "interpretation" of the image separate from the "archiving" of the original image as it came from the camera and medium.</p>

<p>That's probably enough for this post. I can surely run to at least seven more commandments. but this is enough for argument.</p>

 

<p>Thanks, JDM! And please keep them coming...I'm in serious need of the other seven, too.</p>

<p><strong>IV. Keep the original scan, adjust copies</strong><br>

You should always keep the original scan, in high bit naturally. If you make adjustments, they should be on copies of the original, and in TIFF format. The adjusted copies are the new master images. I usually forego cropping, because that's subject to the application, such as printing and framing. Programs such as Lightroom do non-destructive editing, which can be easily reversed or reset. In that case a copy of the adjusted image becomes the master image.</p>

<p>Good stuff. As long as you are in the mood:</p>

<ul>

<li>If you have a print, a slide and a negative of the same image, which should you scan?</li>

<li>I once used Seattle Filmworks in my pre-digital life. They provided all three if I recall. Do their outputs produce superior or inferior scanned image. Or does anyone really remember SFW. </li>

<li>If one has neither the patience, inclination or equipment to do scans, who would you entrust the job to. How much do you have to spend per image to increase the likelihood of getting a good digital image. </li>

</ul>

<p>Jim and Les, this was apparently surplus film and I recall we had this "service" in Australia in 1980 or thereabouts. As a rank amateur in Sydney in those days, I used the lab until it shut its doors almost overnight. Everything I shot for two years faded long ago. My best scan efforts after multiple passes result in a sort of faint image, after endless time on the scanner. I lost a great many shots I would now cherish if I had them. Lesson learnt.</p>

<p>JDW at home in Tasmania</p>

<p>JDM's timely post and good advice has motivated me to share a few additional points learned after much effort and (too much) time spent scanning over the past decade. <br /><br />1. Get dedicated portable hard disks for your scans.This sets the scanned work apart from your regular storage and backup systems, and may prolong the usable life of all those precious archival scans. I use an electrical plug-in Western Digital 2TB portable disk with my original scans, and a computer plug-in Western Digital 2TB portable disk for work copies. I also keep work copies in folders in my desktop computer. <br /><br />2. Keep everything on the scanner turned off. ALL post processing effects (sharpening, color correcting etcetera) should be done after scanning. <br /><br />3. Carefully sort out images to be scanned before you start to scan. In 2013 we found a long lost folder of 2,000+ family pet images, mainly B&W and color negatives, many dating to the 1970s and 1980s. Two thorough culls reduced the work load down to about 700 and I am now devoting one evening each week to the scans. The end result will be an album of about 50-60 8x8 images of the best shots of our once beloved cat and dog family members. Well worth the effort, but can easily become sanity-eroding if not done with care. Music and good red wine also goes a long way to making this task bearable.<br /><br />4. Get the best scanner/s you can afford.After struggling with a (now long obsolete) Canon flatbed scanner with so-so results, when I retired in 2012 I did some research and finally opted for an old but unused demo Plustek for the 35mm, and an Epson Perfection V600 I for the 645, 6x6 and 69. The Plustek software was maddening (designed by and for perfectionist Germans) and the Epson software was not quite up to what I wanted, and I finally bought VueScan, which does everything just fine. Like Edward, I scan in TIFF, and live with huge files. Western Digital storage is cheap nowadays. You may want to do your less important images in JPEG. Entirely your choice. <br /><br />5. Plan your scanning time carefully. Set yourself a sensible scanning schedule and stay with it. Scanning is tedious, but it need not be brain cell destroying. I've found color slides to be the slowest (also the most difficult) to scan and a good evening's work for me is 2-3 yellow Kodak boxes scanned. Color negatives seem to scan well without having to shed any blood or sweat. B&W negatives can be fiddly but results are fine. I clean the originals with care, usually one or two light blasts with canned air and that's it. <br /><br />4. Don't aim for total perfection in your scans. Pick the best initially and scan at the highest level. And yes, keep those originals, or the best of them. Let common sense prevail. Chill and make the best of it. A lot of scanning is automated and you can do other enjoyable things during the scan time. <br /><br />After 50+ years in the darkroom printing I am relieved to be out in the light and finally enjoying other things while my scanners whirr away. One has only so much time and it is up to use to use it to our best advantage. <br /><br />This post is entirely too long, but as a (now retired) newspaper journalist and design architect, I'm used to lengthy and detailed writing. I am also long-winded. My thoughts, hope all this will be useful to some. <br /><br />JDW at home in Tasmania</p>

<p>Gee, thanks for the further additions. I got as far as above and kind of petered out, so this is all to the good.</p>

 

JDM - IMHO, your recommendations are right on the mark. They are in line with the recommendations made by the

National Archives, the Visual Resources Association and other organizations for the (digital) preservation of raster

images.

 

This page lists documents describing various relevant recommendations:

http://vraweb.org/resources/cataloging-metadata-and-data-management/best-practices-and-procedures-guides/

 

Now, if we can only convince people that it is important to follow such recommendations, we will be in good shape.

 

Cheers,

 

Tom M

 

PS - FYI, JDM, I retired from academia last year and am having a great time hiking, backpacking and otherwise getting

back in some semblance of shape ... of course, I'm not going to mention the increase in length of the honey-do list, LOL.

<p>My advice for 35mm slides, at least, is it to not use a scanner and use a good copying setup instead.</p>

<p><strong>V. Catalog your images so you can connect the scan to the original source, in either direction</strong></p>

<p>A relational database, by definition, has one record for each original item which may be accessed in many ways. This record should have a unique identifier. For images, this can be a folder and image name or number, as long as the combination is unique (duplicate only for backup). For film, this can be a roll number and frame number.</p>

<p>The connection between the source and image can be tricky to establish and maintain. What if a slide gets jammed in an automatic feeder (almost guaranteed every session), or you need to repeat a scan? Have a plan and stick to it.</p>

<p>The numbers attached by the processing lab are useless for cataloging purposes. I assign a date code (reverse Hungarian) and a roll number or letter for that day. Once scanned, I cut the negatives into strips of six (35 mm) or four (6x6), etc., and store them in archival (polypropylene) pages. Slides are either returned uncut (best for scanning) or mounted and stored in numerical order in archival pages. I print the date/roll ID at the top of the page. Each image is named with this roll ID and the frame number. The images go in folders with the roll ID, plus a brief description of the location or subject.</p>

<p>For example, slides would be P160929A ("P" for positive, reverse date code and roll number). Negatives would be N160929A. Roll film would be PM or NM ("M" medium format). The type of film is not needed for cataloging, but helps me know what to look for. The actual film is stored in date order, regardless of format. The folder name might be "P160929A PNet Example"</p>

<p>I avoid naming images with catchy titles. It's too hard to think of unique names, and one slide or image might serve many purposes. That's the "many from one" concept of a relational database. If I name an image, it always includes the catalog number for reference. Software like Adobe LightRoom make it easy to assign images to groups for easy retrieval. Only the locations are copied, not the actual image. As a database, LightRoom is not very robust nor scalable. Enterprise systems would be better off using Oracle.</p>

<p><strong>VI. Cutting Film</strong></p>

<p>If you have a roll feeder, scan uncut rolls, if available. I cut film so that all of the strips are as long as possible, for easier handling. Since the leader is usually longer than the trailer, I start cutting from the last frame and work to the top. If there are one or two frames at the beginning, I trim the leader to remove the clip holes, but not longer than the length of the pocket (e.g., 6 frames). If the roll was stopped short, I might start cutting at the top and leave a longer trailer. Whatever works.</p>

<p>Jim, I think the first-generation original image from Seattle Filmworks (and other services that simultaneously offered slides, prints, and negatives) was the <em>negative,</em> not the slide. I used a similar service (Dale, I think) in the 1970s. They respooled Kodak motion-picture film (negative film) into 35mm cartridges and sold it to the public as still-photography film. They developed the negative, then made prints and slide copies, and finally returned all three to the customer. So the negative, not the slide, is the first-generation image and is probably the best one to scan.</p>

<p>Examine the negative's edge markings, which should encode the film type. You can Google these codes to identify the film. As I recall, 5254 was a common 1970s Kodak motion-picture film that was respooled in this manner. Other film stocks were respooled as well. These markings would suggest that the negative is the first-generation image.</p>

<p>But if the slides have faded less than the negatives, then by all means scan the slides. Or even the prints! My slides and negatives from those services have faded significantly since the 1970s. And they weren't so good to begin with, which is why I didn't shoot that film very long.</p>

 

<p>Yes, as mentioned above by several, there are many manuals, guidelines, and other documents available on-line and in forensic text books. A Google search will reveal many of these. I have a bunch of digitized documents, but they are a little large to post here, and are not necessarily superior to those available on line.</p>

<p><br /> What I've given above, and what I hope to do more of later, is to emphasize the preservation of the original images, per se, among other things.</p>

<p>Sometimes, people tend to try to do too much in just one step, often degrading the very information that they are trying to preserve.</p>

<p>JDM, I meant to say, but forgot in my rush to type all my earlier text, many many many thanks for the effort you have put into this post. Also similar thanks to all the others who have contributed. In all ways, a lively topic, this. With much valuable information. I have learned a great deal from all the posts. One is never too old to self-apply the old dog, new tricks philosophy.</p>

<p>Edward, your point is most important and I fell foul of this last year while scanning some 30-40 rolls of old B&W films. In my rush to finalise the post processing, I inadvertently changed the file numbers but didn't update the new numbers on the original negative files, the final results being I now have about 20 rolls of post processed scans, but no clue whatsoever as to where the originals are. Lots of work ahead for me. A valuable lesson learned. </p>

<p>Again, thank you all. I wish more posts on photo.net were like this one.</p>

<p>JDW at home. </p>

<p>I recall shooting weddings in the 60's, long before digital or even scanning (okay, we used drum scanners of sorts to transmit photos for the UPS wire service), service bureaus would require negatives cut into singles, and the desired cropping marked on the glassine envelopes with wax (aka grease) pencil.</p>

<p>At the newspaper, our negatives would be cut into short strips, folded into the assignment sheet and filed in something similar to shoe boxes in the "morgue." It actually worked pretty well, if you've heard the term, "file photos.". The half-tone plates were melted down and recycled daily.</p>

<p>In my last year with the paper, photo engraving was replaced with "scanners" which relayed light and dark from prints to a hot needle which engraved a plastic plate directly. Before photo typesetting, there were Linotype machines. Remember "ETAOIN SHRDLU", the middle row of keys? There was a machine which fit over the keyboard which translated a standard "ASDFG HJKL;" typewriter keyboard to Linotype so the editorial staff could enter copy directly. Operators would hand a fresh slug to a curious neophyte (like me), holding it carefully by the corners with toughened fingers. They're about 300 degrees at that point.</p>

<p>ETAOIN SHRDLU was always one of my favorite authors (<a href="https://en.wikipedia.org/wiki/Etaoin_shrdlu">link</a>). :|</p>

 

<p>I've been working on the problem of archiving scientific (and forensic) images for a long time. I've completed (several times) the digitizing of a huge archive of professional and personal images. Being in a philosophical mood, and feeling a little "apotheosized", I thought I'd lay down some commandments for anyone who is interested.<br>

If you're not interested, why are you still reading this?</p>

<p>Like several better known systems of ethical rules, the first commandment<br /> is<br>

<strong>I. Do no harm.</strong><br>

Always keep the original slide/image. If the pessimists are right, and digital is ephemeral, then the original may have survived well enough to be re-scanned. If the realists are right and entropy will engulf everything, it couldn't hurt.</p>

<p><strong>II. Copy the image.</strong><br>

What you want for archival work is to reproduce the surviving image as close to the real, existing slide as you can. If the film is magenta-hued, the archival copy should be also. If it’s grainy, so also, etc. You are, of course allowed to do <strong><em>non-intrusive</em></strong> cleaning of any dust on the image.<br /><br /><br>

Turn off as much of the “dust reduction” and the like as you can in your copying workflow. At the best, dust reduction will be neutral, but at its worst, you are achieving “dust free” by blurring the image. Dust cleaning can be done automatically or manually later to copies, not to the "archival" image from the scanner.<br /><br />Ditto for color correction and other such processes. <br /><br /><br>

This is, of course, in reference to evidential images. If you are scanning images of the family puppy (Hi, Begheera), turn on all the automatic crap you can find if you can stand the results.</p>

<p><strong>III. Scan once, scan high.</strong><br>

The reason I have "completed" my scans more than once, is because I tried to save time and effort by making only small copies of the originals. <strong><br /></strong><br>

If the images are archival, START by scanning as high resolution and quality as you can. It will save time in the long run, believe me.</p>

<p><strong>Subtotal</strong><br>

I emphasize that I'm talking about evidential imagery, not your personal snapshots. The problem I'm addressing is that of people not approaching digitization of older images in a systematic way, mixing up different levels of the work flow. The key here is to keep "interpretation" of the image separate from the "archiving" of the original image as it came from the camera and medium.</p>

<p>That's probably enough for this post. I can surely run to at least seven more commandments. but this is enough for argument.</p>

I have a question for you, JDMvW. I apologise if you've already answered this elsewhere.

 

I have been making gelatin silver prints for three years. I scan negatives in advance of printing sessions rather than making contact sheets. Bizarrely, it is only recently that I have started making direct comparisons between digital scans of silver prints and digital negative scans. Much to my disappointment, the negative scans are vastly superior; the silver print scans are muddy by comparison. I'm now in a process of elimination, working to find the nub of my problem. I suspect that enlarger alignment is the main fault, but suspect that there may be others. My question is this: are negative scans made with my Epson Perfection V550 Photo scanner inherently better than any silver print that I could make from the same negative?

re negative scans made with my Epson Perfection V550 Photo scanner inherently better than any silver print that I could make from the same negative?

 

i doubt it would be better than any print you "could make", but apparently they are better than the ones you are making. Printing is not a 'neutral' stage, and a scan of a negative is one step closer to the original, so to speak,

 

Most of us are not and never will be as capable as Ansel Adams in the darkroom, but Photoshop does give us 'duffers' a somewhat better and easier way to a good work product. ;)

 

Of course, sometimes it makes things too easy for some people:

 

"correction of Adams image":

April Popular Photography

Edited June 10, 2019 by JDMvW

i doubt it would be better than any print you "could make", but apparently they are better than the ones you are making. Printing is not a 'neutral' stage, and a scan of a negative is one step closer to the original, so to speak,

 

Most of us are not and never will be as capable as Ansel Adams in the darkroom, but Photoshop does give us 'duffers' a somewhat better and easier way to a good work product. ;)

 

Of course, sometimes it makes things too easy for some people:

 

"correction of Adams image":

[ATTACH=full]1298968[/ATTACH]

April Popular Photography

Thank you for your response, JDMvW. Ironically, prints I'm making from 35mm negatives are closer in overall sharpness to scans of the same negatives than are prints I've made from 6x6 negatives. I'm going to use the scan as a yardstick and aim to get prints as sharp. That should keep me busy for... well, the rest of my life, I guess.

i doubt it would be better than any print you "could make", but apparently they are better than the ones you are making. Printing is not a 'neutral' stage, and a scan of a negative is one step closer to the original, so to speak,

 

Most of us are not and never will be as capable as Ansel Adams in the darkroom, but Photoshop does give us 'duffers' a somewhat better and easier way to a good work product. ;)

 

Of course, sometimes it makes things too easy for some people:

 

"correction of Adams image":

[ATTACH=full]1298968[/ATTACH]

April Popular Photography

A follow up question, JDMvW. I've spent a lot of time recently trying to understand why my negative scans appear so much crisper/sharper than my prints. I am now coming to the conclusion that maybe it's not the prints that are inferior, it's the scans of the prints.

 

Is it possible, then, that the same scanner (Epson Perfection V550 photo) can make nice, crisp scans of negatives and dog rough scans of prints? I scan 6x6 negatives at 800 dpi and 8x10 prints at about 400 dpi.

Is it possible, then, that the same scanner (Epson Perfection V550 photo) can make nice, crisp scans of negatives and dog rough scans of prints? I

I'll throw in my thoughts on the subject for free.

1) Epson flatbed 'film-scanners' just aren't the sharpest. They throw out lots of pixels, but not half as much detail. Their scans should be easily beaten on sharpness and detail by a good print 10" x 8" done on glossy paper.

2) If the flatbed scanner's focus is adjusted for its filmholder(s), then the focus on the glass platen will be less than optimal, and vice versa.

3) Even allowing for sub-optimal platen focus; the extra magnification of a 10" x 8" print should more than compensate and give a detailed scan from such a print.

4) Most proper, dedicated (i.e. not a flatbed) CCD film scanners of modest specification (3200~4000ppi) are easily capable of grain-sharp scans. Most flatbeds aren't.

 

Why, then, are your scans from prints not sharp?

 

The obvious culprit would be prints that aren't grain sharp to begin with, and this could be due to poor enlarger alignment, vibration during exposure, a poor-quality enlarging lens, or poor focus. All areas for scrutiny.

 

Poor scan quality from a pin-sharp print can really only be due to poor scanner focus at the platen, or possibly a lack of contact of the print with the platen.

 

Obviously, these are things that can't easily be diagnosed at a distance without seeing the setup, or any results thereof.

 

FWIW. Some time ago I did a comparison of a 600ppi flatbed scan of a 10x colour print (effectively 6000ppi), with a direct 2700ppi scan of the negative. The detail in the print-scan was superior. I would expect a direct scan from a 4000ppi filmscanner to be much closer, as is a 24 megapixel digital camera copy of the same negative.

 

Edited July 13, 2019 by rodeo_joe|1

Thanks, Rodeo_Joe.

 

Also in the "controls" look for what resolution is set for the print scans as opposed to the negative scans. I don't know the Epson, but these could be set to different resolutions on my Canon scanners.

Some Epson scanners, I believe the 700/800 series use two lenses and focus points:- One for prints which sit flush against the glass. The other for film that sits above the glass in the film holder. I believe the V550 use one lens and focus point. But checks the specs to verify.

Good advice OP!

 

I do tons of scanning. Beside photography, I also manage a photo, film and ephemera archive. Here is a rundown on the 3 methods I use...flatbed scanner, sheetfed scanner and copy stand photography.

 

(Article has a few nudes in it.)

 

SHOOTOUT…Flatbed Scanner vs. Sheetfed Scanner vs. Copy Stand Photography

Good advice OP!

 

I do tons of scanning. Beside photography, I also manage a photo, film and ephemera archive. Here is a rundown on the 3 methods I use...flatbed scanner, sheetfed scanner and copy stand photography.

 

(Article has a few nudes in it.)

 

SHOOTOUT…Flatbed Scanner vs. Sheetfed Scanner vs. Copy Stand Photography

I'm surprised that the camera copies aren't better than they are. And by why you're not using flash to obviate any vibration.

 

From the picture of the film reel, it very much looks as if there's too much diffusion on the copy lamps, and that they're set at a steeper angle than 45 degrees, or are set too close to the copyboard. Any of those things will result in low contrast and/or emphasis of surface reflections and imperfections from the artwork.

 

Used as shown, that book copier is going to give pretty poor copies, due to page curvature and shading or surface reflections. The only way to do the job properly and without damage to the book, is to press each page under a sheet of glass, and possibly backed with black paper to reduce print-through. Trying to flatten the whole book under glass is almost certain to break the spine or cause other damage to a delicate folio. So each page must be carefully flattened separately for truly archival reproduction. Not just plonked under a supposedly purpose-made camera and light source. That might be alright for a quick OCR of a cheap modern paperback, but not for any remotely valuable MS.