Archival scanning of slides and photos

[barthome1]

Hello,

I could use some advise. A friend of mine has conducted historical
reasearch in Oklahoma for over fifty years. It is time to deal with
the massive amount of slides and photos that she has taken. Some of
her friends and I are starting a project to scan it all.

So first question: Is a dedicated slide scanner going to give better
results than flat bed scanner with a slide attachement?

Second question: How high of a dpi resolution should I use to preserve
maximum detail? From experimenting it looks like I don't want to go
below 600 dpi. But I would appreciate comments on other people's
experiences.

The content of the slides and prints are valuable enough not to want to
lose details in the scanning process. So I don't want to cut corners
on the project.

Thanks for the help.

Bart
(e-mail address removed)

 

[bmoag]

A film scanner will yield scans of far better quality than most flatbeds.
Use Digital Ice or whatever the scanner uses to help eliminate dust; however
the slides or negatives should be as clean as possible prior to scanning.
If you have the time and ability to do it the higher dpi you scan at the
better: you may not need all that data for immediate use but who knows what
the scan might be used for down the road. It is also more likely that the
digital record of the image will outlast the film original, not because the
digital record is better but because it is more convenient to store.
If you are scanning 35mm film the minimum you should scan at is 2000 to
2400dpi depending on the particular scanner. This will yield files of
20-24mbs per image.
There is little practical benefit to scanning at greater than 8 bit color
depth; scanning at 12 or 16 bit color depths will dramatically increase the
size of each image file.
Batch scanning is faster than individually tweaking each image but some
images require significant manipulation for best results. If you have a lot
of Kodachromes to scan make sure the film scanner is able to handle
Kodachrome.

 

[Maris V. Lidaka Sr.]

Hello,

I could use some advise. A friend of mine has conducted historical
reasearch in Oklahoma for over fifty years. It is time to deal with
the massive amount of slides and photos that she has taken. Some of
her friends and I are starting a project to scan it all.

So first question: Is a dedicated slide scanner going to give better
results than flat bed scanner with a slide attachement?

Absolutely and without question, yes - get a dedicated slide and film
scanner, and a separate flatbed for the photos.

Second question: How high of a dpi resolution should I use to
preserve maximum detail? From experimenting it looks like I don't
want to go below 600 dpi. But I would appreciate comments on other
people's experiences.

For slides and film, use the scanner's maximum capability - generally
4000spi, and with the Minolta Elite 5400 it's 5400spi.

For the photos on the flatbed, 1200spi should be fine, though you could get
by with 600spi if you are sure you will not be increasing image size in the
future.

Check out Wayne Fulton's site (and/or buy his book) for more detailed
information:

http://www.scantips.com/

Maris

 

[Don]

A film scanner will yield scans of far better quality than most flatbeds.

Definitely! When it comes to archiving, "flatbeds" and "film" should
not even be in the same sentence... ;o)

Use Digital Ice or whatever the scanner uses to help eliminate dust; however
the slides or negatives should be as clean as possible prior to scanning.

Again, a definite: Yes!

If you have the time and ability to do it the higher dpi you scan at the
better: you may not need all that data for immediate use but who knows what
the scan might be used for down the road. It is also more likely that the
digital record of the image will outlast the film original, not because the
digital record is better but because it is more convenient to store.

And, most importantly, digital doesn't deteriorate with time or each
time it's copied!

If you are scanning 35mm film the minimum you should scan at is 2000 to
2400dpi depending on the particular scanner. This will yield files of
20-24mbs per image.
There is little practical benefit to scanning at greater than 8 bit color
depth; scanning at 12 or 16 bit color depths will dramatically increase the
size of each image file.

This is where we differ...

Since one doesn't know the use down the road (e.g. wall-sized
giga-pixel displays, to name one) you should scan at maximum *optical*
resolution of the scanner, and at maximum bit-depth.

Since the purpose of the scan is to archive, it's *essential* to use
the highest quality current technology is capable of.

Your eye may not see more than 8-bits (and virtually all monitors
these days only display 8-bits of color) but 14 or 16-bits is
essential for image editing! You may produce final output in 8-bit (be
it for on-screen viewing or printing) but by editing in 16-bits you're
minimizing any cumulative loss of image data due to editing.

Which neatly brings us to the last, yet most important aspect, of
scanning for archiving purposes:

You should scan "raw"! This means, don't use any of the fancy color
correction and other "enhancements" your scanner software claims to
do. All that can be done later. However, if you use any of it at the
scanning stage, you're stuck with that (arbitrary) choice forever.

Therefore, the only settings you should use are: focus, exposure and,
as mentioned above, possibly ICE (hardware based dust and scratches
removal which is far superior to software plug-ins). Purists also set
gamma to 1 but that's not really necessary IMHO. Switch everything
else OFF! And then switch it OFF again - just in case... ;o)

The resulting raw scan is your "digital negative" which you archive.
Put this in a safety deposit box, and/or give copies to friends and
family (so-called off-site storage in case your house/bank gets hit by
an asteroid.).

Only then you make a copy of the digital negative and edit this copy
to your heart's content. If 5 minutes (or 5 years) later you decide
you don't like the edit or the conditions change (aforementioned
wall-displays), you have your archived "virgin" digital negative to
roll back any previous edits and re-edit to accommodate these new
conditions, requirements or whims.

Don.

 

[David Chien]

So first question: Is a dedicated slide scanner going to give better

results than flat bed scanner with a slide attachement?
Yes.

Second question: How high of a dpi resolution should I use to preserve
maximum detail? From experimenting it looks like I don't want to go
below 600 dpi. But I would appreciate comments on other people's
experiences.

As high as it'll go. For slides, you can easily do 4000dpi+ and
still pull off more detail than a lower resolution scan. Limit will be
how much more image data you can see between the higher res. scan vs.
lower and if that's of any importance.

The content of the slides and prints are valuable enough not to want to
lose details in the scanning process. So I don't want to cut corners
on the project.

Forget a desktop slide scanner. Here, you'll want to start off at
the Imacon Flextight scanners, then go up from there to drum scanning.
The lower end stuff, including desktop slide scanners (eg. from Minolta
& Nikon at 4000-5400dpi) and flatbed scanners, simply won't be able to
give you the quality an Imacon can get you.

http://www.luminous-landscape.com/reviews/scanners/imacon_comparison.shtml

---

Easiest way here is to find a company that does archival work for
museums and libraries (contact the big famous ones), and have them do it
- they're already setup to do this.

Otherwise, buy any slide scanner, and start scanning!
(This leaves out the obvious as to what it'll entail
slide cleaning
slide pre-scan
image optimization
slide scanning
image touch up
image optimizations
image save
image indexing
repeat.... each round will take at least 5-10 minutes at the fastest
pass assuming you've got clean, spot free slides to begin with and are
using a scanner with digital ICE to get rid of any tiny problems
automatically as well as doing multipass scanning to reduce noise levels.)

 

[Elwood Dowd]

Already some good answers on hardware.

The content of the slides and prints are valuable enough not to want to
lose details in the scanning process. So I don't want to cut corners
on the project.

For any large project you HAVE to go about it with a solid plan.

Would highly recommend setting up a workflow that you can all live with,
regardless of scanning hardware. If there is truly a lot of information
you may wear out a scanner or two in the process. Hardware is easy to
find, but a good solid workflow is worth its weight in gold (and in not
having to re-do a bunch of work).

For example, when I first began archiving my wife's considerable
collection of genealogical information I simply saved photos with
descriptive names. "aunt-charlotte-and-dog.tif" for example. However,
now I have a huge folder of several hundred photos and no idea who aunt
charlotte (or her dog) might be. Plus, this file was scanned at 300dpi
and thus can't really be enlarged. And the original? Who knows which
shoebox it is in at this point.

These days I take the time to do it right, for my needs. You should
work out a workflow with those you are working with so you don't tread
on each other or lose things.

1. Organize orginals before beginning. Know what I am scanning first,
be it album, wedding negatives from 1912, whatever.

2. For each scanned item, record stats on a master spreadsheet. I
record the following for each photo:

- filename
- subject (from a list)
- description (plain text)
- approximate date taken
- date integrity (scale 1-5 on how accurate surmised date is...remember
these are genealogy photos)
- people in photo
- source (album name, shoebox, etc)
- logical links---e.g. "charlotte was edna's daughter by frank smith"
- link to further information---e.g. "see smith family file pg 42"

and a few other things, depending on the project. It takes MUCH less
time to collate this information now than it will when you have a
directory full of stuff you have no hope of remembering and have to
reconstruct years later.

3. scan to TIF at approx 8x10x300dpi, or as near to 2400x3000 as I can
get. This means 2400dpi for 35mm slides, e.g., 300dpi for an 8x10
print, 600dpi for a 4x6 print, etc. This gives me enough data to work
with the image and archive at a reasonable size without capturing data I
will never use.

4. No postprocessing at this point. I simply save using a serial
number. I save as TIF and zip the file, but I would not have a problem
saving as JPG with very high quality if disk space were more expensive.

5. Archive logical volumes (e.g. a single album together) with 3 copies:
one on my local hard drive, one on DVD in the safe, and once on DVD offsite.

6. Original goes into an archival sleeve and eventually into a 3-ring
binder. When the binder is full, include a table of contents.

7. If any of them need postprocessing, I make a copy of the original,
edit the copy, and save the edited version with layers alongside the
original file with a -edit suffix, either as TIF or PSD.

8. To get an e-mailable or web version of any photo I shrink to 20% and
save as JPG, or use an automated widget to make a slideshow for me.

Believe it or not, I am nowhere near as hardcore about this as others I
have read about. I don't save 4800 raw scans or anything like
that---the photos themselves are simply not high enough quality, nor am
I likely to need a poster-sized enlargement of aunt charlotte or her
dog, but I may well need an 8x10. If it turns out I need to rescan for
some reason, the originals are in archival sleeves and organized.

hope this helps. workflow and archival are excellent subjects to hash
over again and again.

 

[Preston Earle]

You've gotten some good advice, but there a couple of points I'd like to
add. As to the issue of dust removal and "clean-up", I think you'd want
to consider the importance of historical accuracy before doing a lot of
"automatic" clean-up. What the computer thinks is dust, dirt, or other
artifact may be an important detail in a photo. Maybe the slides and
photos should be physically cleaned before scanning but left in their
archival state with little post-scanning clean-up.

Also, I'd consider the number of images and proposed uses of the files
in making decisions about scanning size and file type. There is a
tendency to think that more resolution is better, but for desktop
scanners this isn't always the case. I'd do some serious testing before
I committed to scanning anything larger than 2400x3600-pixels or so.
Also remember that TIFF files this size will be 20-40MB each (among
friends, depending on compression). A thousand images will be 20-40GB,
not an entirely unacceptable amount of storage, but if there are 10,000
images or more, then the 200-400GB-plus can be daunting. I'd plan to
store all final archived images as medium-quality JPEGs and reduce
storage requirements by 95% with no visible effect on image quality.

Preston Earle

 

[lee mcp]

A film scanner will yield scans of far better quality than most flatbeds.
Use Digital Ice or whatever the scanner uses to help eliminate dust; however
the slides or negatives should be as clean as possible prior to scanning.

Is there a special product available for cleaning slides and negatives?

 

[RSD99]

"lee mcp" asked:
"...
Is there a special product available for cleaning slides and negatives?
...."

I use

(1) "Canned Air" or otherwise compressed air ... such as "Dust Off"

(2) PEC-12, which should be available from any photographic store bigger
than a hole-in-the-wall

http://www.photosol.com/

 

[lee mcp]

"lee mcp" asked:
"...
Is there a special product available for cleaning slides and negatives?
..."

I use

(1) "Canned Air" or otherwise compressed air ... such as "Dust Off"

(2) PEC-12, which should be available from any photographic store bigger
than a hole-in-the-wall

http://www.photosol.com/

Thanks!