T-Max film -- EXPOSURE INDEX AND DEVELOPMENT

I've been runnning some film processing tests of T-Max 400(8x10in.) with T-Max RS Dev.(1:9) using JOBO rotary processor, and I have some questions about the results.

First of all, Exposure Index which came out was 560. Is this pretty normal?? Here is how I found my EI. (I followed the article, "exposure test" in the KODAK book. 1. I set the manufacturer's recommended ISO film speed. That is 400. I exposed 5 sheets of film shooting a gray card (focus at infinity). 2. In the first shot I underexposed 3 stop so that the gray card is placed at Zone 2, and the second shot is -3 1/2 stops (Zone 1.5) , and the third is -4 stops (Zone 1), and so on. 3. I develop the films with T-Max RS (1:9) for 9 min at 75F using JOBO (rotation speed 3 1/2) 4. I read the density of the negatives. Base+fog was 0.06. The negative which is 0.16 was the one which was underexposed -4 1/2 stops. 5. I multiplied film speed(400) by the factor(1.4) on the article. 400 x 1.4 = 560 EI=560 Next, the result of the Development test shows that the normal dev. time is 10min. I set my new system-speed number(560), and shoot 4 sheets of films--which were overexposed 2 stops (Zone 7)and--process them in defferent dev. times, 8min, 9min, 10min, and 11min. The density of negative which is 1.11 was the one was deveoped for 10 min. 5. Thus, the result was EI 560 and 10 min development for grade 2 paper printing. Is this the right way to figure out?? Also, I read the article by J. Sexton about T-Max film ,and his current starting recommendatin for T-Max 400 in a JOBO with T-Max RS 1:9 at 75 degrees is EI 320 for 7.75 minutes and rotation setting on 3 1/2. My result is very different from his recommendation. So, I shot normal subject and processed both in my way (EI 560 for 10min) and in his recommendation (EI 320 for 7.75min) The negative processed by my deta looked OK whereas the negative processed by his recommendation looked a little flat in terms of contrast. Therefore, I thought that what he is saying in the article is that make a little flat neg. and add some contrast later when printing, which yield more beautiful print in stead of adjusting contrast when making neg. Am I misunderstanding completely?? How come my deta is away different from his recommendation?? I used sekonic meter and shunider lens --they are pretty new!! Anyone can help me?? I am beginner of large format. Thanks Anausagi

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