First things First:  Are you sure you want to do this?

This page was developed in the "analog" era of amateur photography.   We are now in the "digital" age in case you haven't noticed..  I wouldn't contemplate using a slide duplicator unless three requirements are met:
  1. You have a lot of work to do.  Hundreds of slides or negatives at least.
  2. You really want simple copies to come out at the end.
  3. You are prepared to spend a lot of time "getting it right"
If you don't have a lot of images  you need to copy, hire a professional.  Kodak will make copies, convert negatives to positives or positives to negatives, or scan nagatives or positives, for very reasonable prices.

If what you want is not just a copy, but to improve, repair, or manipulate the original, or if you want prints more economically than from slides;  you should definitely consider going digital.  Get the originals scanned and work with bits instead of chemicals.  Kodak will do an adequate job of scanning for a reasonable price, or there are several do-it-yourself scanning options.

Using the Cambron slide duplicator

I experimented quite a bit with a Cambron slide duplicator I eventually abandoned the "recommended" technique of using a flash pointed at the duplicator screen - it was just too hard to control; Tiny differences in flash-to-duplicator distance make large differences in exposure; and if you want to adjust the exposure of the duplicate at all, it's all guesswork.

Instead, I have two acceptable techniques; one indoor, one outdoor.

The indoor technique

Instead, I point the duplicator at a bright incandescent light source ( I use a 150 watt soft white), let my camera body actually meter the scene, and use that as a guide to the exposure I eventually make. I either use program mode, and let the camera body select the shutter speed, or use fully manual mode, and adjust the exposure by moving toward the light source until the desired degree of over or under exposure is predicted by the metering system.

Exposures are in the range of a second or two. No tripod is needed, because the whole duplicator assembly, including the slide, is a solid tube. Some filtration has to be used to compensate for the light source. The best thing about this technique is that you can study the frame through the viewfinder and manipulate the exposure and filtration at leisure, with a reasonably wysiwyg interface.

The outdoor technique

It's also possible to use that ansi-standard light source, the sun. The problem with this technique is that the color of sunlight is quite variable, so getting the correct filtration is harder. Use the same setup every time, including approximately the same time of day and weather conditions. Use the same aim point; I recommend either "blue sky" 45 degrees away from the sun, or a white wall which is in bright sunlight.


It's definitely worthwhile to use slide duplicating film, unless you actually want the contrast of your slides to increase. I used Ektachrome slide duplicating film, type 5071. An added bonus is that it is tungsten balanced, so very little filtration is needed to compensate for the light source.

Kodak doesn't rate the speed of 5071, but for according to my notes ASA 8 is a good starting point. This implies an exposure time on the order of 1 second with the Cambron duplicator and a bright tungsten light source close to the diffuser plate.

 The biggest problem with these duplicators is that the viewfinder is quite dark, so it can be difficult to frame accurately. *Constant* vigilance is required to make sure each duplicate is framed square and centered on the original.


I use cheap gels, of the type intended to be used between light source and negative in enlargers without dichroic heads. Just hang them in front of the diffusing plate on the slide duplicator. Since they're not in the image path, the optical quality of the filters isn't important.

My "starting" filter pack is 30C.

Other caveats

  • Some cameras won't work at all with these duplicators, which have to be connected through a dumb adaptor. For example, the minolta 7xi will not trip its shutter unless it can electrically detect a "good" lens. This feature isn't universal in autofocus cameras; my minolta 7000i works fine. Also, this "feature" can be disabled in various

  • mysterious ways, depending on the camera model. On the 7xi, you turn the camera on while holding down
    a couple extra buttons. (I forget where I learned this, and exactly which buttons).
  •  Slide duplicating film is very slow ASA; definitely outside the usual rated range of most cameras. In order to get the metering circuitry to work correctly, you may have to use the slowest rated ASA, and coerce a multiple-stop "overexposure" to effectively jack up the rating. Needless to say, this is likely to severly test the accuracy of your camera's metering system.
  • Extra notes

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