Diluting HC-110 for Ilford HP5
Happy Accidents and the importance of correct temperature
from HC110 Technical Data
For 2 months, I developed using ratios from the dilution from the stock solution table. This is not correct. Developer made using the working solution ratios resulted in a 1:7 dilution of concentrate to water which we can call 2A since it is double the strength of A. This dilution is over 4 times stronger than what I should have been using for my development times for Ilford HP5. Why didn’t I notice? I’m reasonably new to analog and was honestly happy with my results. Until I started attempting to minimize grain.
HP5 ISO 400 developed in HC-110 Dilution 2A @ 25ºC 5 minutes
HP5 ISO 400 developed in HC-110 Dilution B 20ºC 5 minutes
The first photo has significantly more grain than the second, although it aided in the dramatic look. A happy accident. The second photo’s grain is much tighter. Both negatives were scanned using a Nikon D750 and macro lens on a Negative Supply copy stand and 95CRI light source.
When I started using the correct Dilution B, I took some test shots to compare development at 20ºC and 25ºC to determine if refrigerating deionized water was necessary.
HP5 ISO 400 in HC-110 Dilution B 25ºC 5 minutes
HP5 ISO 400 in HC-110 Dilution B 20ºC 5 minutes
The first image has more contrast at the expense of increased grain.
The remainder of the images were developed from the correct dilution B solution
Final Thoughts
I’m genuinely surprised I got any image after developing HP5 in 4x the strength of the developer, 5º warmer. I will stick with the correct dilution B at 20ºC for 5 minutes for HP5 and start playing with agitation cycles.