Tuesday, April 12 2005, 7:35 PM
Acros 100 (120)
Well this was a nightmare to say the least. After 10 rolls I finally nailed it down and not a minutes too soon.
During my initial using HC110 at a dilution of 1:45 the problem I was facing was a short development time that gave near correct densities for zone 1 and 8. With a development time shorter than 5 minutes a contraction of N-1 would be worthless, so I decided to give more dilution to help increase development times and meet target densities. With that in mind, I ended up with a dilution of 1:66 that allowed me to meet targets with a great N development time.
After three tests with this new dilution I was able to set my EI and development time for Normal processing with Acros 100.
Conclusion
Normal processing; 7 minutes 15 seconds, E.I. 50 in HC110 with a 1:66 dilution at 68F (20C).
Ø All test were ran using a Jobo processor with a 5 minutes pre rinse and water stop bath.
Below are my test results for Acros using a 1:66 dilution:
6 minutes 7 minutes
Zone 1 Zone 8 | Zone 1 Zone 8
(80) .03 1.07 | (80) .03 1.12
(64) .07 1.12 | (64) .07 1.19
(50) .10 1.20 | (50) .11 1.26
(40) .17 1.33 | (40) .20 1.38
At seven minutes I was close enough that I could have stopped, but I wanted to run one more test to see if I could get the targets dead on. Results below.
7 minutes 30 Seconds
Zone 1 Zone 8
(80) .03 1.19
(64) .08 1.27
(50) .13 1.35
(40) .21 1.42
After seeing the results on the densitometer I split the difference and went with 7 minutes 15 seconds as 30 seconds was over and 7 minutes was a bit under? Now onto N+1, the fun?
N+1 Results
This went a lot smoother than the normal test as I was able to dial it in after three tests. The one thing I noticed with Acros is that zone 8 shifts very quickly in density with small changes in development time, with the shifts being very large.
For N+1 development and EI is as follows;
9 minutes 45 seconds, E.I. 100 in HC110 with a 1:66 dilution at 68F (20C).
Below are my test results for Acros using a 1:66 dilution:
8 min 30 sec. 9 minutes
Zone 1 Zone 8 | Zone 1 Zone 8
(160) .01 .84 | (160) .01 .92
(125) .04 .94 | (125) .03 1.04
(100) .08 1.06 | (100) .08 1.19
(80) .13 1.18 | (80) .15 1.35
| (64) .23 1.47
After seeing the results I decided to make a one-minute jump in development time to see where that fell.
10 minutes
Zone 1 Zone 8
(160) .01 1.04
(125) .04 1.17
(100) .10 1.35
(80) .19 1.50
(64) .28 1.70
I decided to stop testing and give the film a 9 minutes 45 seconds development time for N+1 as viewing the above data I think a 30 second reduction would be too much.
