There are actually two topics in this thread. One is about stains, the other is about chemistry. They are not connected in any way. The spots around the edge have nothing to do with chemistry.
Absolutely!
And even the chemistry has two lines.
1) Infosol 3:
Maybe you can't distinguish between an Ilford film developed at 1+9 from one developed at 1+14 unless you compare them side by side.
Foc mentioned:
"I don't have any test results between 1+9 and 1+14. I know Ilford mention a small trade off in quality, but I haven't see it with my own eyes. To me, they just looked the same.
My reason for using 1+14 at 20C was not economy but the longer developing times. Personally, I prefer times longer than 5 minutes"
This is my opinion too. The problem that I had at the beginning or my experience with Lab-box was not related with dilution, but with developing times. So I changed to 1+14 as Foc said. Another improvement was using a long presoaking. The reason why is that you can think in emulsion like a sponge, it needs certain time to get completely fill of water in order to allow an even development in short time, five minutes is a safe time. Somebody in the lab pass me the trick of adding drops of Photoflow, I thought it was sensible as it reduces superficial tension and would tend to fill "the sponge" quicker. Of course, Photoflow is not absolutely necessary in this stage. So long with Ilford film; I don't know T-Max, maybe is another beast. I hear that T-Max and Delta crystals are not the same. In my case, at the moment, no complains with Ilfosol 3. Maybe a source of problems I have is that I didn't check that presoaking and developing temperature were the same.
2) Mechanical process.
My benchmark is development I carried out in shared lab. There I used D-76, Paterson tank and inversions as Ilford recommended. I'm happy with the results.
When I started development at home, I use at the beginning Lab-box and later an old tank. Both of them doesn't allow canonical agitation, because can't be inverted. You agitate both of them turning the reel with a crank.
So I have a doubt about the agitation being properly made.
I know that Lab-box is very controversial. In my opinion is quite easy to use, and delivers results; for a person with little experience is really convenient. However, I don't know if it is the tool to use in the long run, I suppose that it depends very much on the user.
Conclusion:
Expose a roll in the way of the test for light leaking I found in the old post, and develop it in a canonical way -equalizing temperatures, Paterson, inversion, etc.-, If I find spots, there are light leakage and I have a lot of work resealing my cameras, If there is none, I would have improved my developing process and probably found the cure. Let's see...