Using EOS-M to copy slides/negatives

Larry Rexley wrote:

I spent some time making a slide duplicator for the EF-M 28mm macro lens with several step-up rings, and a bunch of old filters with the glass removed. I found that the setup worked best when the slide film plane was about 32mm from the plane of the front of the ES-22 adapter (43mm filter thread) mounted on the EF-M 28mm lens like so:

Ok that looks SICK. I have a 3d printer, that should be easy to replicate. I'm goint to print a film slider (or whatever they are called) to hold the film in place and avoid light spill from the top of the film which is my biggest issue now I think. This should block 100% of the light coming from outside!

To get a good light source, I used two work lights with 60-watt 3000k LED light bulbs placed 3 inches away from a stack of white printer paper. It is best if they are high quality LED lights with a Color Rendering Index of at least 90 to produce better full-spectrum color source, and I pointed the duplicator at a perfectly uniform part of the white paper, with the slide just a couple inches from the paper. I shot the images using Auto-White-balance with White Priority, but also would white balance in post using the eyedropper on something that was gray or white, when possible.

Do you have an external flash? I read some comments on youtube recommending it but never seen it done. It should allow you to use faster shutter speeds for better sharpness.

Exposures seem to be between 1/8 second and 1/30 second with this setup at ISO 100. It is important to shoot at ISO 100 to get the best dynamic range and most highilght and shadow detail to work with - critical for slide work.

Yup! I am able to go to 1/500 or so which is great because I have a tripod and it's not super sturdy.

If the filter stack is tight and snug, you can use slower exposures like 1/4s as the slide will not move relative to the camera sensor --- but you have to make sure to turn lens image stabilization off through the camera menus!! Otherwise the lens stabilizer will try to compensate for your hand-held motion (if you are hand-holding) which you do NOT want as the slide will move with the sensor and motion of the whole setup should not cause any blurring of the slide. I've gotten tack-sharp duplicates at 1/4 second (see last image below).

The problem with duplicating slides with most setups is that slides have an extremely high contrast range --- higher than a lot of duplicators can output. But the Canon M6ii, M50, and M200 have a great dynamic range that should be enough for most slides. Often you'll have to cut the contrast way back in post, or bring up the shadows pretty dramatically, and/or cut the highlights, especially if the original slide was shot in bright sunlight.

DxO PhotoLab is great at handling wide dynamic range, and as I've mentioned before, has great sharpening and de-noise abilities as well. Experimenting, I've also found that the micro-contrast feature of DxO works well for reducing the excessive grain that older slides often have, by dialing back the micro-contrast below the zero point, almost to the minimum value of the range.

Here's a typical example using one of my Dad's Kodachrome slides originally taken and processed in 1961 (61 years ago) with a vintage Kodak Pony 135 camera, a rangefinder 35mm camera. My dad used a hand-held light meter to determine exposure.

Here's the result right out of the duplicator --- in DxO Photolab 5, I have only white-balanced the image and downsampled it to 2160 pixels high:

1. 1961 Kodachrome slide duplicated with the Canon M6ii & EF-M 28mm f3.5 lens at f5.6, 1/25s, ISO 100

Here's the result after cropping the image and adjusting exposure, downsizing to 2160 pixels high with no other processing:

2. Same image after cropping and adjusting exposure, downsampling to 2160 pixels high

And here's a 'final' image after doing the following:

- Custom tone curve to bring out shadow and midrange detail

- Turn on Deep Prime de-noise, set to +95 to reduce severe grain

- Increase global sharpness to +50 to bring out detail (and balance de-noise sharpness loss)

- Apply unsharp mask of radius 91, Threshold 0, intensity 140 to bring out detail and balance de-noise

- Decrease micro-contrast to negative (-) 95 to further de-emphasize grain and dust

- Increase contrast to +20 to offset loss of contrast due to decreasing microcontrast

- Increase overall color vibrancy and saturation to +10, increase blue channel saturation to +10 to bring out blue in the sky and ocean, reduce Orange channel saturation to -30 to balance the skin tones

- Use the repair tool to 'clone out' most of the obvious dust on the slide (as R2 says it is best to blow or clean the slides before shooting to avoid this as much as possible!). I left a few so that you can see how reducing micro-contrast and increasing de-noise also reduced the impact of the dust fairly effectively

- Downsize image to 2160 pixels high (that resolution still captures all the detail in the image) - downsizing helps reduce the grain further. 'Bicubic Sharper' interpolation was used to preserve detail, and export image quality 85 was used to keep image size reasonable while maintaining very good image quality

3. Final image after processing for tone curve, de-noise, sharpness, reducing grain, repairing dust

Damn. Thanks for such detailed explanation! I'll keep this as a reference to imitate with my setup + software, which is quite different. But I love your results. If I'm honest, I do love #2. I think it looks a bit more organic? But kinda high in contrast too. Maybe the de-noising removed some of the detail in the water in #3. I do love natural grain though.

Finally, here's another slide duplicated.... this was a Kodachrome slide from the late 1990's that I took with a Canon T70 and a sharp Canon lens.

This one needed a lot of color adjustment, but no custom tone curve.... only bringing up the shadows a bit. Similar de-noise and sharpening to the image above --- but I did not need to dial the microcontrast or contrast at all, they were both left at zero.

The train is unsharp as it was moving and the shutter speed wasn't very fast, however the bridge trestle is extremely sharp and shows no grain. This one was downsample to 2160 pixels wide, so is the same scale as the previous image.

4. Burlington-Northern train seen from a trestle on a hike, somewhere out West. Original was a late 1990's Kodachrome slide, duplicated with Canon M6ii, EF-M 28mm f3.5 lens at f5.6, 1/4s (hand-held in home-made duplicator), ISO 500

Beautiful shot. Great scan as well! Crazy sharp!

Amazing work Larry, thanks for sharing! It sure is inspiring and informative!