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Ryuji · 05-06-2007, 01:07 AM

I don't know about that. US Pat 5422845 is Method and device for improved programming threshold voltage distribution in electrically programmable read only memory array.

5248577 is as described.

Anyway, the sensors mentioned in these abstracts cost at least a couple of hundred bucks each. Durable and accurate ones typically used for process control can exceed $1000. A good problem is that these probes are rather bulky in small reacting vessels. But they must be immersed in the bulk solution in such a way that they don't create pockets where the solution doesn't get mixed well. The nozzles of silver and halide jets in the diagram of the second patent is above the solution surface, but that's intentionally deformed. I can't imagine modern Kodak plant using jets that drip solutions into the vessel like that. Usually the nozzles are immersed, often with multiple fine endings, and they are always located very close to the mixing propeller(s), often in a smaller immersed chamber. These silver ion sensor and halide ion sensors are best situated in the immersed chamber, and another set placed in the bulk solution. I wish I had a small research mixing vessel like that but making such thing with 316 stainless or titanium is very expensive.

Anyway, you can go through many of these things, and they are good as a making process controller but not as an emulsion design software. There are too many tweaking parameters taht require experimental measurements. Without doing this, the system can't answer questions like this:

What is the best flow profile or model to make a tabular grain emulsion of average diameter 0.6 micron and average thickness less than 0.04 micron, and optimize everything to minimize reciprocity law failure but the emulsion has to have a shadow speed exceeding equivalent of ASA 100? This is by no means a trivial question but experienced emulsion engineers can tell you a couple of ways to do this in the equipment, gelatin and a host of additives they are familiar with.

Well, like any project, this is doable if you set a realistic goal. But to make an emulsion design software without tedious experimental calibration, you'll need something Kodak and Fujifilm do not have.

05-06-2007, 01:07 AM	#7 (permalink)
Ryuji Join Date: Jan 2005 Location: Boston, MA Posts: 1,238	I don't know about that. US Pat 5422845 is Method and device for improved programming threshold voltage distribution in electrically programmable read only memory array. 5248577 is as described. Anyway, the sensors mentioned in these abstracts cost at least a couple of hundred bucks each. Durable and accurate ones typically used for process control can exceed $1000. A good problem is that these probes are rather bulky in small reacting vessels. But they must be immersed in the bulk solution in such a way that they don't create pockets where the solution doesn't get mixed well. The nozzles of silver and halide jets in the diagram of the second patent is above the solution surface, but that's intentionally deformed. I can't imagine modern Kodak plant using jets that drip solutions into the vessel like that. Usually the nozzles are immersed, often with multiple fine endings, and they are always located very close to the mixing propeller(s), often in a smaller immersed chamber. These silver ion sensor and halide ion sensors are best situated in the immersed chamber, and another set placed in the bulk solution. I wish I had a small research mixing vessel like that but making such thing with 316 stainless or titanium is very expensive. Anyway, you can go through many of these things, and they are good as a making process controller but not as an emulsion design software. There are too many tweaking parameters taht require experimental measurements. Without doing this, the system can't answer questions like this: What is the best flow profile or model to make a tabular grain emulsion of average diameter 0.6 micron and average thickness less than 0.04 micron, and optimize everything to minimize reciprocity law failure but the emulsion has to have a shadow speed exceeding equivalent of ASA 100? This is by no means a trivial question but experienced emulsion engineers can tell you a couple of ways to do this in the equipment, gelatin and a host of additives they are familiar with. Well, like any project, this is doable if you set a realistic goal. But to make an emulsion design software without tedious experimental calibration, you'll need something Kodak and Fujifilm do not have. __________________ Info and Photography at silvergrain.org. Users Information for Silvergrain chemicals at silvergrain.info. Last edited by Ryuji; 05-06-2007 at 01:19 AM.