Slide Copying: Scanner vs Duplicator

cooltouch · Joined: 15 Jan 2009 Posts: 9097 Location: Houston, Texas

I started out using my Epson 3170 scanner to duplicate my slides. But even when set to maximum resolution -- 3200 dpi -- it seemed I wasn't getting all the detail. More recently, I bought an Epson 4990. Still, even at its max resolution -- 4800 dpi -- I felt that the maximum level of detail hadn't improved by all that much.

So I bought an Opteka slide duplicator, which is attached to the front of a lens, and which contains an optical element to achieve close focusing. This worked, but it was somewhat of a hassle to use, since I was constantly having to adjust its horizontal position because my lens's front element rotates. Also because I was using a 1.6x crop body camera, it required the use of a zoom because it worked out to a necessary 69mm or so for 1:1 dupes.

Finally, I modified my rig by removing the Opteka's optical element (it just unscrews), threading the copier barrel onto my 55mm f/3.5 Micro-Nikkor, and using 30mm worth of extension tubes. At last, this gave me 1:1 dupes with no other optics in the light path other than the Micro-Nikkor.

Here is a shot of the slide I used for comparisons. It was taken in 1989, Fujichrome 100, Canon F-1 with a Canon FD 50mm f/3.5 macro lens.

Here are the results. The camera for the two slide dupes was a Canon XS (1000D). 100% crops for the ones using the Opteka, 50% crop for the Epson 4990. No post processing of any kind were done.

Epson 4990 scan at 4800 dpi

Opteka slide duplicator with element and Canon EF 28-80mm lens

Customized rig using Opteka, 55mm Micro-Nikkor, and 30mm of ext tubes

If we can ignore the differences in color balance and exposure for the moment, we can see that the dupe using the Opteka with element is clearly sharper than the Epson 4990 scan, and that the rig using the Opteka with the 55 Micro and extension tube is even sharper than the Opteka with magnification element. The last image does look a bit overprocessed, though. I think I may have the camera's sharpness level turned up a bit too high. Still, you get the idea. It's pretty obvious that using a slide duplicator rig something like what I put together does a clearly better job than even a good quality scanner. And speaking of the rig, here it is -- showing both the slide and roll film stages.

ManualFocus-G · Expire: 2014-11-24

Wow, fascinating stuff! I've got a slide duplicator hanging around here that I haven't tried yet (I hoard all sorts of crap it seems Laughing

). I will first try it with a zoom as in test 2, as I have a number of slides from my old Praktica BX20 which I'd like to see digitised. Many thanks for demo! Smile

cooltouch · Joined: 15 Jan 2009 Posts: 9097 Location: Houston, Texas

Here are some more examples of slides I've duped using the above described rig with the Micro Nikkor. All slides are Kodachrome 64 and were taken in Southern California during the 1980s.

Canon F-1, Vivitar S1 28-90mm f/2.8-3.5

Canon F-1, Vivitar S1 28-90mm f/2.8-3.5

Canon FTb, FL 35mm f/2.5

Canon F-1, Vivitar S1 28-90mm f/2.8-3.5

poilu · Expire: 2019-08-29

nice demo and great samples from 30 years ago

cooltouch · Joined: 15 Jan 2009 Posts: 9097 Location: Houston, Texas

Well -- more like 20 to 25 years ago, but who's counting? Cool

Thanks, btw.

ludoo · Expire: 2011-12-05

Interesting. I have an Epson 4490 which produces very soft scans, and even trying to adjust the film placement makes little difference.

I might try a slide duplicator to scan b&w film I shoot with my analog cameras (btw nice Canon RF in the pic, which model is it?), but I'm a bit puzzled by the crop factor. You write that you need a 69mm focal length to compensate for the 1.6 crop factor, but going by logic it seems that the focal length should be wider to include more in the frame. Can you clarify this a bit for me?

If I can use my Flektogon 35mm (which already focuses very close) with extension tubes instead of having to buy a macro lens, it could turn out into a very cheap scanner replacement. Unless I *do* need a macro lens for its flatter geometry etc. I'm a total newbie at macro.

cooltouch · Joined: 15 Jan 2009 Posts: 9097 Location: Houston, Texas

cooltouch · Joined: 15 Jan 2009 Posts: 9097 Location: Houston, Texas

One other comment I feel I should add that is generally true with slide duplicating, no matter the method you use, as opposed to scanning the slides, is the issue of contrast. Copying slides increases contrast. This was true back in the days of film and it's still true in the digital age. Scanners, on the other hand, do a better job of controlling any increase in contrast. Thus, a scan will probably provide better image detail in the shadow areas of a copy than a dupe, but at the expense of resolution.

A couple of methods used by people who duplicated using film was 1) use a special, fine-grained low-contrast film made especially for duplication, or 2) use Kodachrome 25 and "prefog" it to reduce contrast. Prefogging was a technique where the film was prefogged by triggering a flash at low setting and small lens aperture prior to the regular exposure. This required the use of a camera that permitted multiple exposures, or the very careful respooling of the film onto the camera's take-up reel so the frames are aligned.

I've used both methods, and I was not really able to tell much difference between either. However, even when using the special slide film or prefogging K25, there was still some contrast build-up.

With my DSLR, I have run into almost the exact same problem, although it isn't quite as severe. What I do to counteract this problem to some extent at least is to turn down the contrast setting in my camera's selection menu. Then in Canon's Digital Photo Professional software, where I can make non-destructive changes to the RAW files, I may increase or decrease the contrast even further, depending on the requirements of the individual image. And then in my image processing software, where I have finer control over contrast settings, I may make a final adjustment to it, all the while doing my best to retain shadow detail.

ludoo · Expire: 2011-12-05

Michael, thanks for your extensive replies.

I read about the contrast issues, but strangely the crop you show above taken with the DSLR+duplicator shows more details in the shadow than the scanned one. I'll try to get a cheap duplicator and a set of extension rings and make a few tests, if it works better than my 4490 I may be able to save (uhm, spend on lenses) the money I wanted to spend on a dedicated film scanner.

As for the Canon RF, I had a IIF a while ago and it was a marvellous camera. I sold it to finance my DSLR but I keep checking auctions and will probably get another one (a 2nd series like yours or maybe a later V L etc.) sometimes in the future.

cooltouch · Joined: 15 Jan 2009 Posts: 9097 Location: Houston, Texas

Yeah, there's something about Canon rangefinders. I'd like to add a P to the IIIa. Of all the more modern Canon RFs, I like the P the best.

Regarding the slide dupe's preservation of shadow detail, well I was very careful to preserve as much as I could. With the scan shown and with the dupe using the Opteka's element, I might not have been as observant during post processing.

Your 4490 is a good scanner, and is on par with my 4990 as far as resolution goes -- they're the same generation of Epson scanners. It's just that it doesn't work as well with 35mm as we need. However, I find that the 4990, and even my old 3170 (max claimed 3200ppi), works great for medium format slides and negatives. So if you have medium format photos, try scanning them with your 4490. I think you'll be impressed.

Yeah, now that I've demonstrated to my satisfaction that I can obtain critically sharp copies of my slides using my DSLR, I don't see much point in buying a dedicated film scanner. I would rather put that money toward a future DSLR purchase, one with a higher megapixel count than my current one has.

trifox · Expire: 2014-05-29

Hi Michael..

the result with Micro-Nikkor -- simply rocks!

Can you tell me, if there is something similar applicable on EOS 5D Mark II?

And also -- does this work on negative film, i.e. BW or coloured?

Thanks!

GREAT PICTURES !! - I love film BTW.

tf

cooltouch · Joined: 15 Jan 2009 Posts: 9097 Location: Houston, Texas

Hey Trifox,

Well, I'm using my old Micro-Nikkor with a Canon XS DSLR, so something like this will work fine with your 5D Mk II. I don't know without trying, but you would probably have to use a different combination of extension tubes to achieve the same result.

But because your camera is full frame, you have a big advantage -- you can use bellows with slide duplicator attachment as they were meant to be used for this purpose. Rather than going with the Canon FL or Autobellows, I'd probably go with a set of Nikon bellows and use an adapter for the camera mount, and a Nikkor lens. But this is mostly because I already have a Nikkor macro.

I've shot dupes of negatives using an old T-mount zoom slide duplicator I also own. It works pretty well, but has an element to adjust for focus distance and magnification. As a result, dupes are only slightly sharper than scans from my Epson. I have a roll-film stage for my rig (as shown in the photo), which allows me to shoot negs as well. But duping negs is tricky. It takes a fair amount of work getting the color balance right, and sometimes I can't quite get it exactly right.

A G Photography · Joined: 11 May 2008 Posts: 1480 Location: Bologna - Italy

I was interested in this system to digitalize 35mm (yep for MF on the Epson scanners 4490, 4990 and my v700 are enough).

My main problem is that I don't have slides mounted, but usually still in rolls and don't knwo if I can make them fit into the opteka system.

cooltouch · Joined: 15 Jan 2009 Posts: 9097 Location: Houston, Texas

PaulC · Joined: 23 Dec 2008 Posts: 2318

Just looked at your test and I don't really follow your logic. It looks to me as if the resolution has exceeded the detail in the last one (the blanket has very little fine detail) and you appear to have sharpening fringes or pixelation created either by attempting to bring up detail through sharpening or by blowing it beyond the native resolution of the sensor (i.e. beyond "actual pixels" view).
With that lens, I believe you need a 27.5mm tube to get a true one-to-one resolution on a 35mm frame. If there was no sign of the image breaking up/blurring out at that resolution then you could be confident that the slide equalled or exceeded the resolution of a 10MP full frame digital camera - which I guess brings in a question about "pixel quality" between crop and full-frame sensors.
Anyway, if the image is blurred and breaking up with 5mm extension it doesn't seem to me to prove it has outresolved the sensor - quite the opposite.
Interesting example, though.

pablo · Joined: 10 Jan 2010 Posts: 6 Location: New England

Can you describe the light source you used for duplicating these slides into a DSLR? Is it a diffusion type or a condensing type? Would that make a difference in a DSLR?

TIA

cooltouch · Joined: 15 Jan 2009 Posts: 9097 Location: Houston, Texas

Hi Pablo,

Wow, I'm surprised I left that important bit of information out. The slide duplicator has a piece of white diffusion plastic that is positioned between the slide and the light source.

Probably most often, people will rig up a strobe as the light source for duplicates. Back in the day when I shot film duplicates of slides, I usually used a small flash for illumination.

But in this case, most often I use a reflective white surface illuminated by the sun during hours close to mid-day. Too early in the morning or late in the afternoon, and the reflected light will take on a yellowish-orange color, which affects the color, and I've found that my camera's white balance doesn't entirely correct for this.

I have also had good results shooting duplicates on overcast days by just pointing the rig skyward and taking the pictures. On overcast days, the skies are a nice, neutral tone which works very well for duplication.

I don't currently own any sort of off-camera flash setup that I can use with my DSLR to do things the way I did years ago, so I just make do with natural light. So far it's worked well.

[UPDATE: Now I use a simple off-camera flash setup with sync cords and a couple of adapters. I mount the flash to a small light stand and point my dupe rig at the flash. I have the flash set to 1/32 power, and for this particular flash model (an old Canon 420EZ) that allows me to position the front of the rig about 20cm from the flash.]

pablo · Joined: 10 Jan 2010 Posts: 6 Location: New England

Hi cooltouch,

Thank you for your reply. I was thinking of using some sort of LED arrangment for a light source. Adorama had a light source that was a small bank of LEDs whose color temperature was 5600k. I can't find it on their website now, but it was about $40.

This would give me a Nikon Coolscan-like light source. Smile

On the other hand, over Christmas, various stores were selling strings of white LED Chistmas lights that I thought maybe I could mount in a grid, and put a diffuser over.

I used to have a Beseler 23C enlarger. I wish I still had the condenser lenses from it, then I could choose between diffuse or condenser type of lighting.

cooltouch · Joined: 15 Jan 2009 Posts: 9097 Location: Houston, Texas

Sounds like you've given this some thought. I've recently constructed a light box for proofing slides. The illumination is two fluorescent light tubes. Unfortunately the light fixtures came with "warm" bulbs, which have a yellow cast to them. I've been thinking about using this light box as a light source for duplicating slides, but I'll probably have to change the bulbs out.

ludoo · Expire: 2011-12-05

If you know how to solder, LEDs are really cheap and very easy to work with: all you need is a current source (say, a 12V adapter) and a handful of resistors.

visualopsins · Expire: 2025-04-11

These are fun: Click here to see on Ebay (the tiny Minolta Mini-35 Slide Projector, only 3.5"x4"x7" in carrying case)

for even lighting:

I bought two because the tripod-mountable lamp-condenser assembly is a single unit, simply removed from the cover with a few screws. (see black unit in first photo) I plan to use it as light source for slide/negative dup. Unit is

Some inventive folks have automated the process using projector without a lens; press the projector advance, press the shutter, repeat... http://babryce.com/slidedigitizer.html

cooltouch · Joined: 15 Jan 2009 Posts: 9097 Location: Houston, Texas

Cool little projector. Yeah, I've seen the projector-duplicator rig. Clever, but it sure helps if you already know something about electronics and breadboarding your own circuits and stuff.

My rig's a lot simpler Cool

my_photography · Expire: 2016-12-25

Is there any different when duplicating/copying a negative instead of slide?I tried copying some few year old negatives last week and the result was horrible. Maybe I am doing something wrong?

By the way what lens are you using when duplicating the slide/negatives? Normal 50mm, 50mm macro or something else?

pablo · Joined: 10 Jan 2010 Posts: 6 Location: New England

cooltouch · Joined: 15 Jan 2009 Posts: 9097 Location: Houston, Texas