From Analog Negatives to Digital Art: A Short Overview of a Technical Solution
I've had quite a few inquiries on how I scan my analog photos and which scanner I use. A lot of people were surprised, if not bewildered when I answered that, for monochrome negatives, I don't use a scanner at all.
In the moment, I use a Sony Alpha 77 DSLR with a Tamron 60mm Macro for DSLR digitzing. Generally, I would say any good DSLR with a large sensor (megapixels really count here!) is good. A good macro lens is essential because of the close distance to the negative. It must be good if you want to make 2 or 4 (or more) shots of a single negative, because distortions or unsharpness on the edges absolutely lead to bad results.
For backlighting, I employ a 19" computer lcd monitor that is lying on it's back side (by pure luck the one I use is perfectly flat and parallel to the front). I took the LCD panel out, as well as all the polarizing and fresnel sheets behind the panel. Only the diffusor sheet remains. I put a thin glass plate over the monitor that covers the whole top. This eases handling and prevents the diffusor sheet from being scratched or collecting dirt/dust. Cost: Zero. A good, professional light box can also be used, but it needs a color temperature controlled light source that has an even emmitance over the spectrum (some cheap LED types don't do well in that regime) .
The camera is mounted on a Kaiser enlarger stand, which is rock solid. I took the enlarger head off and mounted a repro adapter from Kaiser instead. Instead of the repro adapter (expensive) one can use an own creation made of a cheap sliding camera rail, but that places the camera off the table center towards the support stand. This limits the use for max. 4x5. The repro adapter reaches farther to the center of the table, upon which the backlight monitor is placed.
6x7 negatives are usually digitized with two shots. The camera is set up for manual exposure. I use f:8 to f:11 for a bit more DOF to counter out of DOF wandering of slightly warped negatives. Exposure time is determined by analyzing the histogram (the Sony does that in real time). This is essential for good results, because you want to capture as much of the dynamics of grey tones as possible and keep the histogram curve within the recordable bounds. You will notice that many negatives will deliver more than the camera sensor can catch, so you'll need to find the sweet spot. Experience teaches that eventually. Focusing is also manual / uncoupled. The Sony displays red marks that visually show when sharp contrasts correlate with a on spot focus. Also a non flickering green center mark signals a perfect focus. All shots are saved in the RAW format, of course.
The glass plate negatives just sit on the backlight box, of course. 6x6 and 6x7 are in a nifty digitizer frame called "Digitaliza". This tool works quite well and I can recommend it. For larger film negs like 4x4 /9x12 I use strips of cut glass to hold down the edges and prevent warping. All negatives are digitized with the emulsion side facing upwards to the camera. This is better for the sensitive emulsion because no physical contact can scratch it and the results are better because you are not capturing through the clear film base. I never handle negatives with bare hands and wear protective gloves. I use special laboratory type compressed air bottles for a quick blow to remove dust or lints prior to digitizing. I'm careful not to spray the propellant on the negatives and only deliver short blows.
After digitizing, I merge the usually two halves of the negatives in Photoshop. This usually works fine, but it can be problematic when you have large unstructured parts (grey sky or black) in the areas that merge. That can throw off the merging algorithm and you might need to move the camera a bit further away or use a single shot. Two exposures per negative result in a ca. 50 megapixel image with the camera I use. After cropping the excess it usually results in a 40MP rendition. This does not at all cover the resolution a sharp 6x7 photo with what, say, an Ilford Delta Pro 100 can produce! But it is more enough for the web and it is fun to explore these huge photos. Besides that, you have plenty of space to crop or choose compositions.
Next in the workflow is checking the focus. I do that by searching for lints or dust specs. Normally a nuisance, they are welcomed here because if they show up nice and crisp I know that my recording focus was spot on and any unsharpness is within the analog exposure.
Further work after merging in Photoshop is done: convert to 16bit, convert to grayscale, rotate, mirror horizontal, and then use the CF Systems ColorPerfect plugin to convert the negative to a positive. I could elaborate on why I use this plugin, but that would be too much for this article. Just check www.c-f-systems.com/Plug-ins.h…
After that I clean up the negative by stamping out the lints, dust specs or other anomalies. Then I save it as PSD and do the rest of the post processing and archiving in Lightroom. Here I straighten and crop the photo, if necessary, as well as make little changes to brightness and contrast. You also can determine by analyzing the histogram, checking if the distribution of the grey tones is OK and no values exceed or don't reach the bounds. I usually adjust the blacks and whites so that areas that should be exactly in the range of these values (maximal / minimal zone according to the zone system) deliver the RGB value accordingly. Can't trust any monitor for that by just looking at it. Sharpening is of very little use. You only make the grain sharper at higher settings, which looks ungainly and can produce weird artifacts. After all has been done I export the capture as JPEG.
All in all, compared to a full resolution scan, this method is very fast, you have full control over the resolution, and can digitize almost anything from 35mm to huge glass plates in a very good quality.