Nice One, ANDYYYYYY!

[John Wiegerink]

With 4 or 5 min in just Bath A my "test' developed very nicely, a bit thinner than with B part, but totally usable.
Actually, after a few rolls in full A+B process, you can nicely develop film in just bath B too. Yes, I was thinking WTF-That is imossible and then I tried it. It works. So I start using single use bath B.

You're implying that there is that much carry-over into bath "B" that you can get full development in bath "B" alone? I guess if I were to go the two-bath developer route, I would likely pick Thornten's two-bath and dump or mix fresh bath "B" after one or two films. Otherwise, you would have an inconsistent developer.

 

[Donald Qualls]

Actually, after a few rolls in full A+B process, you can nicely develop film in just bath B too.

Or in other words, Barry Thornton may have been fooling himself...

 

[Andrew O'Neill]

You're implying that there is that much carry-over into bath "B" that you can get full development in bath "B" alone? I guess if I were to go the two-bath developer route, I would likely pick Thornten's two-bath and dump or mix fresh bath "B" after one or two films. Otherwise, you would have an inconsistent developer.

I was thinking the same so, no more than two 8x10's per bath B, then mix up a fresh bath.

 

[gorbas]

You're implying that there is that much carry-over into bath "B" that you can get full development in bath "B" alone? I guess if I were to go the two-bath developer route, I would likely pick Thornten's two-bath and dump or mix fresh bath "B" after one or two films. Otherwise, you would have an inconsistent developer.

Hi John, Unfortunately, Yes. I had long history of using 2 bath developers some 30+ years ago, but never until recently tested how single baths of it works. In my mind I had very idealistic picture of reaction and how carry on from previous bath properly develops negative if it's soaked in emulsion and rest of it magically get "sanitized" and neutralized. Far from it, there is serious accumulation of metol & sulphite in bath B. Raghu and me had long discussion about it a year and half or 2 years ago and then I did test. I think everything started with some Carl's 2 bath formula. Raghu proposed new single use bath B with sodium hydroxide that I think was published by here by Gainer. Other way is to use just inexpensive borax as single use bath B or live with slightly more expensive single use of Kodalk.

Sorry for quick and dirty Iphone snap. The first 2 bath developer I ever used was home brew and had slightly acidic bath A. On my ToDo list is to make that developer again and try is bath A capable of developing film on it's own.

 

[John Wiegerink]

Hi John, Unfortunately, Yes. I had long history of using 2 bath developers some 30+ years ago, but never until recently tested how single baths of it works. In my mind I had very idealistic picture of reaction and how carry on from previous bath properly develops negative if it's soaked in emulsion and rest of it magically get "sanitized" and neutralized. Far from it, there is serious accumulation of metol & sulphite in bath B. Raghu and me had long discussion about it a year and half or 2 years ago and then I did test. I think everything started with some Carl's 2 bath formula. Raghu proposed new single use bath B with sodium hydroxide that I think was published by here by Gainer. Other way is to use just inexpensive borax as single use bath B or live with slightly more expensive single use of Kodalk. View attachment 325070
Sorry for quick and dirty Iphone snap. The first 2 bath developer I ever used was home brew and had slightly acidic bath A. On my ToDo list is to make that developer again and try is bath A capable of developing film on it's own.

I would have never guessed there would be that much carry-over in such a short time to induce development in bath B, but obviously there is. In order to keep things as repeatable as possible, one should probably use bath "B" as a one-shot then. I have more than 20Lbs. of Kodalk so I could do that rather cheaply since the Kodalk was given to me anyway. I don't use two bath developers much anymore, but just might use it with some of my erratic 120 folding cameras. Thornton's two-bath and old folders should be made for each other.