What workflow for film scanning and archiving?

Archived from groups: rec.photo.digital (More info?)

My personal experience after several years of scanning personal images:
A general dpi for 35mm scans that is large enough for most uses is 2400 dpi
at 8 bit color depth. This creates files large enough to facilitate
retouching and printing at sizes even greater than 8.5 x11. Most film
scanners have default settings for 2000dpi, which is not all that different
than 2400 dpi, due to the mechanics of the image sensor movements, and will
be faster per scan than 2400 dpi.
If you are scanning Kodachrome be sure your scanner is capable of handling
that emulsion. Kodachrome has unique characteristics that lesser film
scanners, including some older high end units, cannot handle.
If you have a specific reason to scan at larger dpi and 16 bit color that is
up to you; if you have no clear understanding of why you might want to
create larger image file sizes there is no good reason to do so, unless you
feel your images are priceless and must be archived at the highest
resolution and bit depth possible.It is unlikely your heirs will appreciate
the time and effort that went into archiving the images in that fashion
unless they are obsessive-compulsive about all things photodigital.
You are correct that archiving in a lossless format like tif is preferable.
TIF files will be more accesible to casual users than proprietary formats
like Photoshop's PSD or DNG.
A 2400/8 bit scan yields an image size of 24mbs. If you store at the highest
quality jpeg settings the actual corruption of data will be minimal and file
sizes will be reduced by about 75%. However it is best to stay with TIF.
If your scanner allows you to choose a color space use AdobeRGB as this will
preserve the widest range of color practicable and be useful if you plan to
maintain color management.I am not a fan of 16 bit color depth for general
use unless one has a clear understanding of the benefits and pitfalls of
that wider gamut. If your scanner only records in sRGB you are not missing
anything vital compared to losing the film original without having first
made a decent scan.
Storage on DVD media is more practical than CDs for large numbers of high
resolution images.

Archived from groups: rec.photo.digital (More info?)

Bob <BobFlintsTone@spam.com> wrote:
> On 14 Sep 2005 02:15:17 GMT, "Thomas T. Veldhouse" <veldy71@yahoo.com> wrote:
>
>>What is the typical workflow for film scanning and archiving? I have a
>>couple of thousand slides [mostly kodachrome] from the 1950s and 1960s
>>that I would like to scan. Granted, I will probably only scan select
>>images, but for the sake of argument, let's say 50% or 1000+ images. If
>>I scan full resolution TIFF files I would only get about 6 scans per CD
>>... no good. So, what workflow do most people use? 16-bit images?
>>8-bit images? TIFF? PSD? JPEG?
>>
>>Oh yes ... what good is the stupid NEF file format that the Coolscan
>>printers offer ... nothing of value supports the format and it saves no
>>space. It would be nice to be able to convert these scans over to DNG
>>format files, just for compatibility with the pictures I take with my
>>D70.
>
> I have scanned in a ton of slides, usually as 14m TIF files... about the same
> res. as the D70... thats 50 per CD...
>
> NEFs do save space... they are about 30% the size of the original file... and
> you can get plug-ins for Photo Shop and Windoze Viewer...
>

NEF files seemed to be the same size as a corresponding TIFF. Photoshop
could read the file, but it is not a modern version of .NEF, as I could
not convert it to DNG format.

--
Thomas T. Veldhouse
Key Fingerprint: 2DB9 813F F510 82C2 E1AE 34D0 D69D 1EDC D5EC AED1
Spammers please contact me at renegade@veldy.net.

Archived from groups: rec.photo.digital (More info?)

bmoag wrote:

> My personal experience after several years of scanning personal images:
> A general dpi for 35mm scans that is large enough for most uses is 2400 dpi
> at 8 bit color depth.

While 2400 dpi may be fine for higher ISO films done hand held, it is very
inadequate for tripod mounted fine grained film images. Note too
that scanner ratings are higher than they should be. By this I mean
that consumer scanners, in the many I have tested, rate about
2/3 the ppi compared to drum scans. Thus a 2400 ppi scanner
is really more like a 1600 ppi drum scan. If you want real 2400 ppi,
you need a 3600 ppi scanner. The highest resolution films,
like kodachrome and velvia have information above 4000 ppi
(drum scans), so if you have images that are critically sharp,
you need a 5000 ppi scanner, and a bare minimum of a 4000 ppi
quality scanner. I've also found benefit in scanning at 12-bits
per pixel when I want to maintain detail from deep shadows to bright
highlights.

Roger Clark
photos, scan info at: http://www.clarkvision.com

> This creates files large enough to facilitate
> retouching and printing at sizes even greater than 8.5 x11. Most film
> scanners have default settings for 2000dpi, which is not all that different
> than 2400 dpi, due to the mechanics of the image sensor movements, and will
> be faster per scan than 2400 dpi.
> If you are scanning Kodachrome be sure your scanner is capable of handling
> that emulsion. Kodachrome has unique characteristics that lesser film
> scanners, including some older high end units, cannot handle.
> If you have a specific reason to scan at larger dpi and 16 bit color that is
> up to you; if you have no clear understanding of why you might want to
> create larger image file sizes there is no good reason to do so, unless you
> feel your images are priceless and must be archived at the highest
> resolution and bit depth possible.It is unlikely your heirs will appreciate
> the time and effort that went into archiving the images in that fashion
> unless they are obsessive-compulsive about all things photodigital.
> You are correct that archiving in a lossless format like tif is preferable.
> TIF files will be more accesible to casual users than proprietary formats
> like Photoshop's PSD or DNG.
> A 2400/8 bit scan yields an image size of 24mbs. If you store at the highest
> quality jpeg settings the actual corruption of data will be minimal and file
> sizes will be reduced by about 75%. However it is best to stay with TIF.
> If your scanner allows you to choose a color space use AdobeRGB as this will
> preserve the widest range of color practicable and be useful if you plan to
> maintain color management.I am not a fan of 16 bit color depth for general
> use unless one has a clear understanding of the benefits and pitfalls of
> that wider gamut. If your scanner only records in sRGB you are not missing
> anything vital compared to losing the film original without having first
> made a decent scan.
> Storage on DVD media is more practical than CDs for large numbers of high
> resolution images.
>
>

Archived from groups: rec.photo.digital (More info?)

In article <432787b5$0$37835$8046368a@newsreader.iphouse.net>,
Thomas T. Veldhouse <veldy71@yahoo.com> wrote:
>What is the typical workflow for film scanning and archiving? I have a
>couple of thousand slides [mostly kodachrome] from the 1950s and 1960s
>that I would like to scan. Granted, I will probably only scan select
>images, but for the sake of argument, let's say 50% or 1000+ images. If
>I scan full resolution TIFF files I would only get about 6 scans per CD
>... no good. So, what workflow do most people use? 16-bit images?
>8-bit images? TIFF? PSD? JPEG?

If you are really worried about the loss (or deterioration) of the original
frames, then scan at 4000 or 5400 ppi with a good scanner, in 16-bit/ch.
possibly (on Nikon scanners) in multi-sample mode.

The big problem however, is that you first need to learn how to scan.
Otherwise you may find halfway through that you made some small mistakes in
the first half.

Note that a 1000 4000 ppi scans is just 128 GByte. It is best to keep the
scans on-line and on redundent harddisks (optionally with backups on DVD).
It best to compute MD5 (or better) sums of all scans and verify those
checksums regularly (at least once a year). Needless to say off-site
starage is a good idea.

Another approach is not to keep the original scans, but to make color
corrected 8-bit/ch versions. Jpeg works fine for that: correct any color
balance problems, remove dirt, and make sure that contrast fits in 8-bit.
Keep the original resolution and do not sharpen. 4 MByte per frame give
excellent jpegs at 4000 ppi. That way the whole project stays at just 4
Gbyte.

You can combine the second approach with storing high res raw scans of
really excellent frames (or frames that are otherwise important, or
hard to color correct).

>Oh yes ... what good is the stupid NEF file format that the Coolscan
>printers offer ... nothing of value supports the format and it saves no
>space. It would be nice to be able to convert these scans over to DNG
>format files, just for compatibility with the pictures I take with my
>D70.

As far as I know the scanner NEF format is unrelated to the dSLR NEF format.


--
That was it. Done. The faulty Monk was turned out into the desert where it
could believe what it liked, including the idea that it had been hard done
by. It was allowed to keep its horse, since horses were so cheap to make.
-- Douglas Adams in Dirk Gently's Holistic Detective Agency

Archived from groups: rec.photo.digital (More info?)

Roger N. Clark (change username to rnclark) wrote:

> Thomas T. Veldhouse wrote:
>
>> "Roger N. Clark (change username to rnclark)" <username@qwest.net> wrote:
>>
>>> While 2400 dpi may be fine for higher ISO films done hand held, it is
>>> very
>>> inadequate for tripod mounted fine grained film images. Note too
>>> that scanner ratings are higher than they should be. By this I mean
>>> that consumer scanners, in the many I have tested, rate about
>>> 2/3 the ppi compared to drum scans. Thus a 2400 ppi scanner
>>> is really more like a 1600 ppi drum scan. If you want real 2400 ppi,
>>> you need a 3600 ppi scanner. The highest resolution films,
>>> like kodachrome and velvia have information above 4000 ppi
>>> (drum scans), so if you have images that are critically sharp,
>>> you need a 5000 ppi scanner, and a bare minimum of a 4000 ppi
>>> quality scanner. I've also found benefit in scanning at 12-bits
>>> per pixel when I want to maintain detail from deep shadows to bright
>>> highlights.
>>>
>>
>>
>> Would I be correct to indicate that this type of scan would more benefit
>> work in progress and be less of a benefit for archival purposes? Or do
>> you honestly archive 130+ MB files?
>
>
> Yes I do archive such files. In fact, my 4x5 scans are 1 GByte each.
> The work of scanning and fixing defects is huge compared to the cost and
> effort of saving the file. I save to firewire drives which I keep offline.
> I actually use two drives which I alternate backups (soon I'll go to
> three).
> Drives are cheap compared to the effort I've done to get the images
> in final form.
>
>>
>> My general rule for doing work right from film is to scan at max 16-bit
>> resolution and work in AdobeRGB until I get to the images final form, at
>> which time I target the image (so .. 8 x 10 @ 400 dpi converted to a
>> printer colorspace ... usually 8-bit) for final output. A reasonable
>> compromise for archival purposes is where I am having trouble. If there
>> was a useful way to shrink the large image in a similar manner to RAW
>> from a camera put into NEF format, that would be great (I assume there
>> must be some selective loss somewhere).
>
>
> If you intend to print once and never again, I might agree with
> your strategy. But printing technology has been constantly evolving,
> so making your final archive file tied to a specific printer
> color space is like freezing the image in time, and may never
> be able to print again.
>
> I archive my original scans to DVD, then the processed final scan
> is archived to hard drives and DVD, one set of each is stored
> off site. I also create printer profiled images for specific
> printers. I typically have an 8x10 for my inkjet, and then
> lightjet Fuji Crystal Archive files at full resolution. Then
> for various print sizes (e.g. 11x14, 16x20, 24x30, 30x40...),
> when I create the file and have a print made, I archive the
> interpolated image profiled for the printer. I archive
> each of these as my time to recreate them is more
> than it takes to archive them.
>
> Example:
> image1.tif (final image,
> usually 16-bits/channel)
> image1-lightjetprofile.tif (same resolution as final image)
> image1-LJ24x30.tif (interpolated, sharpened reduction
> of image1-lightjetprofile.tif)
> image1-LJ11x14.tif (interpolated, sharpened reduction
> of image1-lightjetprofile.tif)
> image1-inkjet8x10.tif (interpolated, sharpened reduction
> of image1.tif with inkjet profile)
>
> All the above get archived. If a new printer comes along, I can start
> from the original.
>
> For snapshots, I do not do this. I save jpegs only (highest quality).
> For my 4x5s, archiving one image requires 3 to 5 gigabytes.
>
> Roger

Hi...

I second your what you said, though additionally I keep one 48 bit
untouched straight from the scanner copy as well (no grain, no dust,
nothing at all) based on the premise that we can't possibly know what
the future holds in terms of better software, printers, etc. And blank
dvd's cost almost nothing.

Ken

Archived from groups: rec.photo.digital (More info?)

"Roger N. Clark (change username to rnclark)" <username@qwest.net> wrote:
>
> Ken, I do that too, as I said "I archive my original scans to DVD."
>
> Roger

Thanks all! I think that settles my archive problem. I will be
archiving the 130MB files scanned at 4000 dpi @ 16-bit (14-bit
actually), which is the limit of my scanner. I will experiment a bit
with ICE4 and averaging to see if it is worth doing this for every image
(I suspect it is worth doing ICE4 for every image).

--
Thomas T. Veldhouse
Key Fingerprint: 2DB9 813F F510 82C2 E1AE 34D0 D69D 1EDC D5EC AED1
Spammers please contact me at renegade@veldy.net.