Posted a few duotone images of mushrooms to Flickr. Didn’t mean to spend this morning making these images, but when you get the right subject matter, there is an eerie presence to toned images: Maybe it’s the intersection of image qualities that recall old photography and emulsions hand-coated onto paper coupled with high tech display and printing—or maybe the mushrooms (just shitakes) have an effect on me.
This tutorial on duotones over at Luminous Landscape was useful.
Can’t soft proof a duotone in Photoshop. Have to convert to RGB to soft proof; however, the color changes in subtle ways.
One way to compare the images is by checking their histograms.
The duotone image is just a little darker on average (mean 106.97 compared to mean 112.53), and it clearly has pixels in the darkest bins, including a spike of 0% black over on the left edge of its histogram. The RGB image has no black pixels until you reach level 11, about a 4% gray.
Comparison of RGB and duotone image histograms
You can use Curves adjustment layers to compare the dynamic ranges of the two versions of the image. Option-drag on the black point or the white point in the Curves dialog to see where in the image the darkest and lightest values are found. The duotone reveals solid black (0%) in a few places. The RGB version has no solid blacks. In the light tones, the two are practically the same.
Continue reading ‘Duotone Soft Proof’