The toning of these images was done with a Photoshop set of
actions called "epaperpress". This Photoshop action set can
be downloaded *here*. And the specific action from that
set used here is called "Silver Gelatin".

When the "Silver Gelatin" action is used, leaving the layer at
100% opacity seems to make the image look way too much sepia color
(see bottom image).

However, I imagine this Photoshop "Silver Gelatin" action was
designed this way so that we might change the opacity of the
layer and decide for ourselves the degree of seeming toning
that reminds us of chemical based silver gelatin photographic
papers

For my own part, when the opacity of the toning layer is reduced
down to about 25% opacity, the very subtle green of this toning
(the middle image here) as compared to the image with no toning
applied) somewhat reminds me my earlier physical darkroom days
and of the common look of Iford's Ilfospeed resin coated paper,
or Ilford Ilfobrom fiber based paper.

And this, I imagine, is how this Photoshop action was designed
to be use -- employed for our black & white images, and to give
a relatively subtle degree of toning which perhaps most resembles
the look of B&W photographic papers, or resembles how those
B&W might look when in a physical darkroom we chemically
toned (usually subtly) our B&W pictures.

CJ