HC-110 dilution H - minimum amount to use

Hi,

I plan to use HC-110 (actually Legacy Pro L110, but believe they're functionally if not chemically identical) to develop -
- HP5+ @ 400
- Kentmere 400 @ 400
- Kentmere 100 @ 100

I am planning to use Dilution H i.e. half of Dilution B, i.e. 1:63

- I use a Paterson tank to develop 2x36 exp rolls (actually bulk-rolled about 40-42 exp per roll)
- It takes 600ml developer. For ease of use I am planning to use 640ml i.e. 10 ml of HC-110/L-110 and 630ml water

The question is - is 10ml HC-110/L-110 all right? Because I read somewhere that you must take a minimum of 10 ml of HC-110 per roll (and increase the overall quantity of solution to maintain the strength). So is my plan to use 10 ml developer for 2 rolls at a time, sensible? Of course I will try, but these are rolls with images I want to keep, and testing on 2x42 exp rolls is beyond my means, hence the question.

Many thanks.

I've used (old) HC-110 at dilutions up to 1+119 (Dilution G?) and always got good results. For 35mm in stainless (which I used at that time) that's just over 2 ml of syrup for a roll of film. You're using about 2.5 times that much. You'll be fine.

If you extrapolate the Kodak capacity information for HC-110, you will end up with the conclusion that Kodak recommends 6 ml of concentrate per roll.
Most likely there is a significant safety factor built into that, but as I am quite conservative about such things ....
That is one of the reasons I settled on Jason Brunner's 1 + 49 recommended dilution, which effectively is the same as dilution E (1 +47).
Here is Jason's article on that dilution: https://www.photrio.com/forum/resources/hc110-made-simple.220/

Thank you both! While I "think" (and "measure") in metric units... I will go with the dilution H, for the reason that it's easier to measure 10ml (for 640ml total solution) vs. 12ml (for 600ml total solution) i.e. it's easier to measure 10ml than 12ml...

I am planning to use 2x times specified for Dilution B. I read a fair bit and that sounded like it should work, too.

This should be a fantastically economical developer. Can't wait to try it (as soon as I finish off the Ilfosol... which does not like to wait around).

I've always used 6 ml concentrate per 80 sq inches of film. I agree with Matt that you could probably get away with less than that, but why risk it?

Ilfosol, you said? Fantastic developer.

Yes you should be ok. But for my films I use dilution B, where B stands for Bulletproof.