Why is Zone V 50% gray?

[Kirk Keyes]

Ralph - did you work up your Reproduction Cycle graph by hand, or do you have some software that you did it in? I'd love to get ahold of some software that can do that sort of thing...

[Helen B]

Helen

I couldn't make that work. This formula returns 0.496 for K=50% and it should return 0.71 [0.66 (theoretical gamma) + 0.05].

What numbers are you using for DR and gamma to give 0.496?

Best,
Helen

[RalphLambrecht]

Helen

I used DR = Dmax - Dmin = 2.10 - 0.05 = 2.05, and gamma = 2.2.

[RalphLambrecht]

I do it 'manually' in Adobe Illustrator. It's more flexible than any customized software would be. Also, the curve smoothing abilities are unbeatable. It takes about 1/2 hour to do modify my template for a new film, paper, scanner, imagesetter etc.

[Helen B]

Ralph,

How did you arrive at that gamma? Something around 1.5 would fit that DR and mid-grey better.

Best,
Helen

[RalphLambrecht]

Helen

This is my monitor gamma.