ESR Portraits : Analog Photography

Scanning Film with a Digital Camera

At one time the measure of a good negative was the ease or difficulty it provided in making a paper print with an enlarger. Sadly the technology for creating analog prints from color reversal appear to have been lost forever. I still value a B&W negative that prints easily, but in most cases ease of scanning is even more important because the digital representation is the first and maybe only way that other people will see the photograph.

Digitizing

For 35mm and medium format I prefer a digital camera over a consumer-grade scanner for several reasons: speed and control over exposure.

To get started with macro photography you'll need a tripod with a reversing post such as the Slik 700DX Pro and a light pad with a high color reproducability such as the Kaiser Slimlite Plano 8x11.

Always use the 2-second self-timer to get to get a sharp image. You probably need to use manual focus, but contrast-based systems are also good enough. I usually take macro shots at f/8 or f/9.

Adjustments

In my experience, the first edit is never your final adjustment. Walk away from the computer and come back an hour or a day later. In a way, you are partially blind while making an initial composite. With the passing of time you will almost certainly perceive each frame (and the collection as a whole) differently.

I generally keep Gimp files for two weeks, if I'm still happy with them I export them as a tiff and delete the intermediate files.

B&W Negatives

Black and white negatives capture a relatively wide tonal range which does not map the linearly to the digital camera's dynamic range. This means that you will almost want to adjust the shadows and highlights using an s-curve. (This vaguely mimics the restrainer in the highlights and depletion of halides of shadows on photo paper.)

Another technique, and one that I use quite often is to use the Grain Merge blend mode to simultaneously deepen the shadows and brighten the highlights. I then use the +1 layer to restore some information lost in the shadows.

B&W reversal bracketed scan

Layer Mode Opacity Mask
-1 Normal 100% -
0 Gain Merge 90% -
+1 Normal 10% -

Color Reversal

Slide film is a real joy to inspect by eye, but requires creativity to scan because it has subtle details embedded in the shadows. Because of this I always auto-bracket by 1 stop. There are many complex ways to combine the three exposures using luminosity masks. but I will list the most strait-forward technique I know of.

The concept is to pick up some of the shadow detail by adjusting the opacity of layer "0" over layer "+1", then restore color and detail in the bright areas by merging the underexposed frame using a layer mask.

Color reversal bracketed scan

Layer Mode Opacity Mask
+1 Normal 100% -
0 Normal 90% -
-1 Normal 50% Mask from image on
"+1" layer

Alternatively I may use this arrangement to create more contrast

Layer Mode Opacity Mask
+1 Normal 100% -
0 Normal 100% Mask from image
-1 Grain Merge 20% Mask from image

Color Negatives

Color negative film is easy to develop, but very difficult to scan because it has no inherent color balance. For this reason I avoid color negative film if possible.

80A filter colorcube comparison

You loose two stops of light using this filter, so skip this if you need to.

Color adjustment is the second step. If you are in a hurry you can use the filter such as Auto White-Balance (as it's called in Gimp) which will stretch each channel. One problem with this is that it clips areas of low and high intensity. This sort of adjustment only works well if you apply it once to three separate exposures and fiddle with the opacity of each layer to balance the colors.

Final color correction is hard. In Gimp you might get close by using Mid-point eyedropper in Levels. More likely you will need to adjust curves. I have found the following envalope to work reasonably well with Fuji Pro 400H

Color Negative Adjustment curves

This is a preset I save called my Color Envalope gives you six control points, two for each channel that work by giving you separate control over compression of hilights and shadows as well as relative saturation.

Scan Resolutions

Using a digital camera

Pixels/mm 56 41 MP
30 1680 1230 2.1
40 2240 1640 3.7
50 2800 2050 5.7
60 3360 2460 8.3
70 3920 2870 11.2
80 4480 3280 14.7

Drum scan resolutions

PPI 56 41 MP
2400 5292 3874 20.5
4800 10528 7708 82.1

Last updated on November 02, 2019