not sure if you searched here for dk50 threads
might be helpful ...
i have never heard of diluting it as you suggest. the best use of dk50 is straight, with sheet film.
i used it for a long time as i was a lab-person for a portrait photographer trained in the 20s/30s ...
i processed armloads of 5x7 sheets of tri x and tri x ortho, straight never dilute developer in deep tanks.
the trick with a lot of deep tank developers is they need to be mellowed to work best.
that means not to dilute them, but to process a bunch of film in them so they get oxidized
and then use it. i replenished ours for a certain number of films through it, and then when i mixed fresh
i left about 1/3 a tank of spent developer to mellow the new, so it would work right ...
besides 5x7 sheets, i processed my own 4x5 (hangers) and 35mm ( on a bent coathanger ) in the same tanks
and got very good results. grainless, nice contrast ...
i wish i could be of better help for dilute dk50 ...
digitaltruth doesn't even have times for this developer, dilute ...
if you have a green safelight, you could always develop by inspection
and get a better idea on what your times should be.
there is a very good article here .