It is no secret that the 2500 reels in a Jobo do not always produce a nice, flat and uniform density across the negative using Tmax developer on Tmax film (and perhaps other film stocks as well). An additional problem is Kodak's recommendation against using Tmax developer with sheet film, and who wants to deal with two different Tmax developers?

Thus began my quest for a cast-iron reliable way to get consistent results from my Jobo. First, I decided to load only four sheets rather than six, which allows for enough space between sheets to prevent fresh developer from "catching" in the narrow spacing you get with six sheets. BTW, I do not have the weird clips you are supposed to fit onto the reels to prevent turbulence and to keep the film from sliding out of the grooves. The next change I made was running a four-minute presoak. Curiously, when I dump this out the water is a bright blue. My thinking is to wet the film surface so that the developer can get started more evenly across the film surface. Then I add Tmax developer diluted 1:8 at 75 degF. The next change I made was to lower the speed of rotation to the "1" or low setting, about 2 rev/second. This gives a "lazy" rotation that keeps the film wet with developer but does not suck liquid into the grooves on the reel, which causes additional agitation on the edges and thus more density. My standard development is 11 1/2 minutes. I also note that I never see the dreaded "dichroic fog" or staining that is supposed to show up when you don't use the RS version of Tmax developer.

I own a densitometer so I can verify the ISO setting for a Zone 1 density of 0.1, and my Zone 8 density is 1.2 or so, which is in line with Kodak numbers for average contrast, for those zone system enthusiasts out there. The Jobo allows for precise repeatability of time, temperature and agitation, and now that I have tamed the film reel issues, my negatives are clean and free of steaks.

I'll wait for comment on the blue water that emerges from a presoak, and why I have no issues with going against Kodak's recommendation on the choice of developer.