Using a DSLR for digitizing older 35 mm film slides ?

Planapo · Post by **Planapo** » Fri Jan 16, 2009 7:15 am

Dear guys,

I have some older film slides, that I would like to digitize.

My institution provides two scanners that I could use:
1. Nikon Coolscan LS-4000 ED, max. resol. 4000 dpi, bmp or tga files, 24 bit, Firewire
2. Polaroid PrintScan 35Plus, bmp- or tiff-files, 24 bit, SCSI
Thing is, the three times I have been at the graphics lab the scanners were occupied or not working!

Now, as my Oly OM bellows came with the Oly "Slide Copier", I'm thinking I could use bellows and Slide Copier to take photographs of the slides with the Canon 400D.
Should I try this, or would scanning on one of the above mentioned scanners be the better way?

What lens should I use? I thought of an EL-Nikkor or Componon enlarger lens, not reversed as it 'd be shooting below 1:1 (24 mm x 36 mm onto the 14,8 mm x 22,2 mm sensor).

How should I light the diffusor pane of the Slide Copier? Thought of a frosted bulb as the fiber guides of a cold light source might give only uneven lighting.

Anyone been there, done that and can give any advice?
I'm grateful for your input.

--Betty

Harold Gough · Post by **Harold Gough** » Fri Jan 16, 2009 8:01 am

Betty,

The Nikon would scan to the quality you require. (Alamy has accepted some of my trannies scanned on someone else's 4000ED). I can't comment on the other scanner, except that negative scanners are often not good enough (DMax too low) for contrasty trannies.

I understand that digitising via a camera does not give the quality that a scanner does. However:

If I were to copy 35mm trannies to copier film I would use the OM 80mm macro lens. Something equivalent should do the job. I would use flash (TTL metering) as a light source, not so close/powerful that it over-exposes. (I think the OM copier has a bellows cover to keep stray light out of the lens). Whether you need to (ideally) reverse your lens depends on whether the distance from it to the camera is greater than from the lens to the tranny. It might be more practical, in this magnification range, to use a macro lens rather than an enlarger lens.

I hope this is helpful.

Harold

DaveW · Post by **DaveW** » Fri Jan 16, 2009 9:53 am

As far as I remember when I had a Nikon slide copier for bellows the lens shade coupling from the copier just fitted into the lenses 52mm filter thread and they recommended using the then 55mm Micro Nikkor, so evidently they did not think the lens needed reversing.

Also see:-

http://www.photo-i.co.uk/BB/viewtopic.php?t=4439

DaveW

rjlittlefield · Post by **rjlittlefield** » Fri Jan 16, 2009 3:12 pm

Betty, do you mean this device? If so, then definitely give it a try.

With a good lens (ideally the 80 mm Oly, but the enlarging lenses should be OK), you should be able to record all the detail your sensor can handle. That is about 54 line pairs per mm on the film, corresponding to about 2600 dpi.

One advantage of the camera approach is that if necessary you can use short focus stacks to handle unusually curved film.

"Better" has many dimensions. A lot depends on whether you have 10 slides to do, or 100, or 1000.

--Rik

Harold Gough · Post by **Harold Gough** » Sat Jan 17, 2009 12:36 am

By the copying route the biggest problem is likely to be dust on the film. Grease (fingerprints), if present, can be wiped off with products such as Tetenal, which will also take off the dust.

Harold

DaveW · Post by **DaveW** » Sat Jan 17, 2009 1:30 am

Also slide copying tends to increase contrast and clog the shadows a bit, but at least as they are now digital you have some adjustment in post processing.

DaveW

Harold Gough · Post by **Harold Gough** » Sat Jan 17, 2009 2:55 am

DaveW wrote:Also slide copying tends to increase contrast and clog the shadows a bit

If you copy a given film stock onto the same stock the characteristics are additive. Thus, e.g., a contrasty film will give an excessively contrasty copy. Specialised copying film stock would lack impact for primary photography but gives copies much like the originals.

Harold

AndrewC · Post by **AndrewC** » Sat Jan 17, 2009 3:45 am

Using a scanner like the LS-4000 will remove dust and emulsion scratches very effectively using Digital ICE.

Planapo · Post by **Planapo** » Sun Jan 18, 2009 3:59 am

Harold, Dave, Rik, Andrew, thanks boys for your helpful suggestions.

So I will give it a try. Going to light with a bulb from a distance, because I haven't got a ttl flash for this camera yet. But will also try a scanner, if eventually I have access and that Nikon scanner is working as the expectation to have dust and scratches corrected automatically is just too tempting.

Yes, Rik it´s that Oly copier your link is leading to.

Thanks again,
Betty

g4lab · Post by **g4lab** » Sun Jan 18, 2009 2:33 pm

You could correct for the contrast increase and even produce a copy that makes more of its information visible (for ones that might be important) by doing one of those techniques where you take two exposures at different exposure values one to get the shadows and one to get the highlights. Then merge them in post processing.

I think when this is done to take an original picture, they call it "high dynamic range photography", or something like that.

This is definitely a task where digital beats the pants off of film (with due apologies to Harold G.) I used to copy slides on Ektachrome and pre-flash the frame to reduce the contrast. TTL flash illumination of the copier was very handy.
The copies still were never as good as the originals. And my eyes were not presbyopic back then.

Planapo · Post by **Planapo** » Sun Jan 18, 2009 3:24 pm

Gene, Thanks for your additional thought.

Now I have learned a new English word: presbyopic. Sorry to hear that this affects you, know it from my Mum whose arm is hardly long enough when she wants to read something without her glasses.
Must be especially annoying when working with optical devices where one tends to take one's glasses off all the time, at least I have this habit.

--Betty

g4lab · Post by **g4lab** » Sun Jan 18, 2009 4:24 pm

Planapo wrote:Gene, Thanks for your additional thought.

Now I have learned a new English word: presbyopic. Sorry to hear that this affects you, know it from my Mum whose arm is hardly long enough when she wants to read something without her glasses.
Must be especially annoying when working with optical devices where one tends to take one's glasses off all the time, at least I have this habit.

--Betty

It is maybe my least favorite word in the whole language. Thank you for the tea and sympathy. Don't even get me started on the subject. I wear my readers on a librarian neck cord. The chicks go crazy since I started doing that.

Harold Gough · Post by **Harold Gough** » Mon Jan 19, 2009 12:35 am

g4lab wrote: I used to copy slides on Ektachrome and pre-flash the frame to reduce the contrast.

I don't understand pre-flash in this context.

Harold

AndrewC · Post by **AndrewC** » Mon Jan 19, 2009 12:50 am

Harold Gough wrote:
g4lab wrote: I used to copy slides on Ektachrome and pre-flash the frame to reduce the contrast.
I don't understand pre-flash in this context.

Harold

Exposure is a cumulative process but you need to get above a critical or activiation energy to start to see detail, by pre-exposing the film you make it more sensitive to areas which receive very little light during exposure and you push everything to the right on the zone scale. Ansel Adams' "The Negative" has a section on it. Large format guys sometimes call it "fogging".

Harold Gough · Post by **Harold Gough** » Mon Jan 19, 2009 1:37 am

I understand fogging. This is what I imaginged was the possibility but did not believe was your intention. Fogging is what I do my very best to avoid at airports.

What does it do for your highlights?

Harold