I had an idea for a thick emulsion b&w film reversal development but got stuck.

[fert]

Previously, using the D67 to develop inversion on the 5222 always did not get the desired results, such as yellowing and a less-than-transparent image. So I wanted to create a reverse developer for thick emulsions. But due to my lack of knowledge this idea is stuck.
I used CD1 and sodium VC as developer and pushed the ph to 9.5 and developed at 30 degrees C for 8 minutes, at first I got yellowish negatives, later I added ammonium thiosulfate as a silver melter and the image seemed to be normal. But after densitometry it seems that there is not enough contrast. I don't know how to proceed anymore.
I hope everyone can give me some advice as well as recommendations for science data.

 

[fert]

Some questions: How to control the development time at 20 degrees Celsius to 7~8 minutes? Is there a problem with my choice of developer? How can I increase the contrast? Are there other options for silver melt?

 

[Alessandro Serrao]

Previously, using the D67 to develop inversion on the 5222 always did not get the desired results, such as yellowing and a less-than-transparent image. So I wanted to create a reverse developer for thick emulsions. But due to my lack of knowledge this idea is stuck.
I used CD1 and sodium VC as developer and pushed the ph to 9.5 and developed at 30 degrees C for 8 minutes, at first I got yellowish negatives, later I added ammonium thiosulfate as a silver melter and the image seemed to be normal. But after densitometry it seems that there is not enough contrast. I don't know how to proceed anymore.
I hope everyone can give me some advice as well as recommendations for science data.
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There are probably better silver halide solvents than thiosulfate (which if I remember correctly eats density very fast if not carefully dosed).
DTOD comes to mind.
There are also developer accelerators that can be used to obtain clear highlights.
PEG polyethyleneglycols for example.
Finally you have to use sodium hexametaphosphate in the permanganic acid bleach to avoid MNO2 redeposition that cannot be cleared in the metabisulphite clearing bath.

 

[fert]

There are probably better silver halide solvents than thiosulfate (which if I remember correctly eats density very fast if not carefullt dosed).
DTOD comes to mind.

Thanks for the reply, I'll give it a try.

 

[Alessandro Serrao]

Don't develop for too long otherwise theoretically Ag will redeposit too much also in the highlights region...