The learned demosaic was an option under Detail, off by default. It is
now how a Bayer raw is developed: on by default at full strength on
every device — which hardware runs it is the inference engine's choice
— and first in the Adjust panel, since it decides what every control
below is applied to.
Strength (0-100, default 100) replaces Keep grain: grain = 100 -
strength, the same luminance-only blend, so moving it is one GPU pass
and never a re-run. 0.21.0's sidecars stored grain; it is still read,
as the inverse, and never written.
With it on for every photograph, the result is now kept on disk
(denoise.md §7.1, §12): the network's output as half floats, keyed on
a SHA-256 of the file's bytes and the model, oldest first past a 5 GB
budget, beside the inference engine's cache. A reopened photograph and
an export of one already developed read it back instead of running the
network again; a damaged entry is a miss.
Whether to use the learned denoise, and how much grain to keep, are what a
photographer sets, so they travel the one road every setting does: published
as a capability, captured by Preset, stored in the sidecar, replayed by the
undo stack (FR-DEV-3c). Published only on a photograph that can take it, for
the lens switch's reason; the availability is derived from the file and is
not in the state. Off by default, grain 0; a reset returns both.
dtourolle