my HC-110 stand development experiment

I used HC-110 1:100 @20C/72F to develop HP5+ rated at iso 400.
I agitated continuously for the first minute, then left it untouched for 1 hour.
The results are too dense and contrasty, with blocked up highlights.
I guess I need to cut down the total time, and/or reduce the initial continuous agitation?

Covington's HC110 page recommends 1:31 at 5 minutes for this combination with regular agitation. Doubling dilution about doubles time, so you would be looking at something like 15 minutes at 1:100 with regular agitation. For semi-stand I'd cut agitation to 5 minute intervals and add approximately 50% to time for something like 21 minutes. I probably wouldn't go full stand myself, but that's your call.

BTW, the above adjustments are very close to Ansel Adams' times of 18-20 minutes, agitation every 3-4 minutes, 1:30 from stock (stock is already 1:3 dilution), with Tri-X. This was aimed at compensation effects.

Shortening time or increasing dilution would decrease the excessive contrast you got. Be sure to use at least 3 ml of HC110 "syrup" for each roll of 35mm film or 80 square inches of film.

Lee

I just successfully developed two rolls of Kodak Plus-X, rated at box speed, in a dilution of 1.5:200. 500ml per film, which means 3.75ml of concentrate per roll.
Development time was 30 minutes, agitation every five minutes, with the chemistry at 70*F, and 90 seconds initial agitation, rolling the capped tank on the floor. I presoak the film for about 3-5 minutes.

Interestingly, I've been using Rodinal at a dilution of 1:200, also 500ml per film and identical agitation, and the results are remarkably similar. The only main difference that I can see is a bit more highlight density with HC-110.

- Thomas