benzatriazole and HC-110

[icmartin]

How much benzatriazole powder should I add to my HC 110? I used to know but haven't done it in a long time. I did it to get an additional stop of shadow detail. I use working solution B and HP5+. Should I add the benzatriazole to the stock solution or the working solution?
Thanks!
-IC Martin (Ian Martin, the new one, not the Ian Martin who joined the formum before me...)

 

[MikeK]

Never heard of using Benzo to gain an extra stop of speed before, I would have thought it would have the opposite effect. A small amount of benzo will stop a developer dead in its tracks. The main use of benzo is an anti-foggant like Potassium bromide.

Are you sure you really mean sodium sulfite?

- Mike

 

[Poco]

Mike,

I regularly add potassium bromide to D76 to suppress base/fog and thereby get better shadow contrast. I guess it "increases speed" to the extent it makes the lowest densities printable by separating them from base/fog .

 

[Bruce Osgood]

How much benzatriazole powder should I add to my HC 110? I used to know but haven't done it in a long time. I did it to get an additional stop of shadow detail. I use working solution B and HP5+. Should I add the benzatriazole to the stock solution or the working solution?
Thanks!
-IC Martin (Ian Martin, the new one, not the Ian Martin who joined the formum before me...)

Ian Martin The Younger,
I've not used any form of HC 110 but do regularly us a variant of Dektol (D-73) with an additional 10 mL of a 2% solution of Benzotriazol. I have not altered the amount of Potassium Bromide I usually use. I add the Benzo as the last additive in preparing the stock solution and dilute a portion of the Stock to 1+2 as a Working solution.

As Benzotriazole is difficult to dissolve in water I use Isopropyl Alcohol (99% pure) and find no problem in its' dissolving.

I do feel the 'de-fogging' of shadows to allow greater definition but I wouldn't say there is a full stop difference.

 

[icmartin]

more info

When I was in college (UC Davis) I had an excellent professor who suggested adding a 1% benzatriazole solution to HC-110 for processing my HP5+. I haven't done this in a long time and I can't remember how I was supposed to do this... My best guess was that I was supposed to do this to the stock solution and go from there. I do remember excellent shadow detail from doing this. How does this sound? I take benzatriazole powder and add it to the stock solution so that it's 1% by weight. Does that make sense? Is there a better way to go from a dry powder to a liquid by volume? I would then use solution B. I appreciate the feedback!

 

[Dr.Kollig]

Certain formulas list a few ml of 1% Benzotriazole solution, like Crawley FX-37, it says 5 ml for the stock which is diluted 1:3-1:5, giving a total of 0.8-1.25 ml Benz. solution per litre working solution.
So I would aim 1-2 ml of a 1% Benz. solution per litre working solution.

I would add the Benz. solution when you prepare the working solution and not to the stock solution of HC 110.

We rather use 1% Benz.-solution when working with papers to change the tone towards cold or to "repair" fogged papers. We use 2-5 ml per litre of paper developer and adjust from there.

Wolfram