Hey Drew, just a quick note to says thanks for your help with printing 30x40s on the CPI 40. Everything worked out great. Just for the record I was able to figure out how to make the 30x40 CPI 40 drum Kodak test strip compliant. This allowed me to do determine exposure time, enlarger aperture lens setting, and color head CC settings using my Fujimoto CP-51 to develop 8x10 test prints, and then develop the final 30x40 print using the CPI 40 30x40 drum. It was amazing to get the exactly the same results on both machines. If you are interested I can send you the documentation I wrote for making the CPI 40 Kodak test strip complaint.
That said, I also use TMX100 for my mask. However, I do not try to achieve a straight line characteristic curve when developing my b&w mask for my 5x7 and 4x10 color negatives. I have decide that a curved characteristic curve (CC) is better because it will builds up density faster in the shadows than in the high lights. This produces a better light contrast mask (LCM) for color negative film that results in a more normal looking print. To get a curved CC as opposed to a straight line CC, I develop TMX100 using HC110 at a 1:7 dilution of stock solution. I am attaching a family of curves for both 5 and 10 minute development times that I use to predict my exposure time for the mask.
Ektar 100 is not as great as you may think. Its reds are I slightly more exaggerated then 160VC, but 160 VC is better for greens and blues. The big difference is the dynamic range. 160 VC is around 13 stops while Ektar 100 and 160 NC is closer to 9 stops. I have attach a CC graph that compares the CCs for Portre 160 VC, Ektar 100, and Portra 160 NC. Both the CCs for 160NC and Ektar 100 show notable fall off of gamma or film contrast at Zone IX. The graphs are only through Zone X, but you can see both the CCs for Ektar 100 and Portra 160 NC start to fall off a Zone IX while Portra 160 VC keeps climbing.
I have also attached bar graphs for the red, green, and blue layers for the Macbeth chart as well.
Thanks again....
PS I was not able to upload the blue or green layers for the Macbeth bar graphs(4 files is the limit). I will do it in my next posting.
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