Robert D Feinman

Using Color Film to Make Black and White Prints

Black and white film is obsolete!

Not black and white photography, just negative film. As explained in Scanning Black and White Negatives , negatives have a limited tonal range and thus fit the dynamic range of film scanners poorly, This produces images with poor gradation, unless hi-bit (12-16 bit) scans are used.

Color transparency film is much better fitted to the range of the scanner with a density range of 3.0 to 4.0 rather than the range of less than 2.0 for negatives. In this tip I'll show  how to produce a variety of black and white prints from a single original. This allows the creative decisions to be made after the exposure, rather than in the field.

Here is the original scanned in color image. A nice white church on the Big Island of Hawaii taken on a slightly overcast day.

The third column shows a color spectrum.

Color Original
Color Original

spectrum wedge
Color Wedge Original

We now select just the green  channel as a separate file and convert to gray-scale. This is equivalent to having taken the picture through a medium green (Wratten #11, X1) filter.

Notice the overall tonality tends to match the color image. This is similar to what a standard landscape photographer would choose to render a "normal" print. Medium green or yellow (Wratten #8, K2) are usually the first choice to balance the sky to foliage.

The third column shows the spectrum under the same conditions. Note green appears white. Real filters would not be this pure.

Green Filter Image
Green Filter Image
Green Channel Green Channel Wedge

But we don't have settle for this treatment. We could give the image an old-fashioned, orthochromatic look by using only the blue channel. The sky is lighter and the foliage darker. 

This would be more apparent if there was any actual blue sky showing. The clouds and the sky would merge together.

The third column shows the spectrum under the same conditions. Note blue appears white. Real filters would not be this pure.

Blue Filter Image
Blue Filter Image

Blue Channel wedge Blue Channel Wedge

But maybe we're still not happy. In that case let's choose the red channel. This gives an image as if taken with a Wratten #25, A filter.

Now we have the typical contrasty sky and almost black foliage on the trees. Very dramatic!

The third column shows the spectrum under the same conditions. Note red appears white. Real filters would not be this pure.

Red Filter Image
Red Filter Image

Red Channel Wedge Red Channel Wedge

We're still not satisfied. So we apply a curve filter to this image as shown at right.

This curve is similar to what would happen if we printed on a grade 3 paper.

The third column shows the spectrum with a curve applied with a big dip in the middle of the red tonal range. This effect is not possible with conventional film except by making color separations and masks. Note color distortions in the middle of the spectrum.

red channel curve
Increased Contrast Curve

Impossible curve Impossible Curve Wedge

Here is the resulting image.  The sky is more dramatic and the whole picture is much more contrasty.

This is similar to what would have happened if we had given the film additional development as is done in the zone system.

So, rather than agonizing over "previzualization" and forcing a single decision when the image was shot, we can explore variations later on. Maybe our original conception was wrong, maybe we couldn't anticipate the actual effect of the exposure or filter on the negative. In any case we have the flexibility to realize our goal later on.

Other variations using the channel mixer option in Photoshop allow for color blending of individual channel to produce intermediate results.

The third column shows the previous impossible spectrum in black and white. Notice the odd tonalities.

Enhanced Red Filter Image
After Contrast Increasing Curve

Impossible in B and W Impossible Curve Wedge B&W

But wait! You want a real, silver-based print. In that case, reverse the tonalities, make some curve adjustments and print out a full-sized negative on clear film.

Using a resolution of 300 - 360 dpi on a modern printer will give a negative that can be contact printed onto any desired enlarging paper. And remember that all burning on dodging can be done on the negative so that the printing in the darkroom is routine, with as many identical prints made as desired.

Before anyone objects too strongly, I'll admit that there is one aspect in which negative film is superior: latitude. The exposure range of slide film is 4 to  6 stops compared to 8 to 10 stops for negative film (especially if given full exposure for shadows). There is even a solution for this, at least for static subjects.

See my tip Photographing "Impossible" Lighting Conditions.

The third column shows the original spectrum set to greyscale. This doesn't produce a very good likeness. Use the channel mixer for better results.

negative image
Negative Image

Standard Image in B and W Wedge set to  B&W
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© 2002 Robert D Feinman