Cold tone developer

I've read a couple threads here where it is suggested to add Benzotriazole (BTAZ) to a developer to make achieve a colder tone. Would this work with Ilford Multigrade Developer? I ask because I have a huge jug of it and it would be nice to use that

Also, how do I go about doing this? I really only have used prepackaged chemicals for up until this point, so the directions are right on the package. I can order BTAZ for not too much at photoformulary, but I presume I just don't dump it into my developer. Would I mix up a solution of some % BTAZ and then add that to my dev? Is that by weight? Do I need a scale? hahaha. Sorry for the questions, I could use some direction here.

You need to try, it's too difficult to predict, make up a solution of IBT - 10gm Benzotriazole + 10 g Sodium Carbonate (anhyd) to 1 iltre of water. Then add this to your developer 10ml per litre of dilute developer, test, then add more if you need to up to 30 or 40ml Keep exposures short and develop fully. 3 mins rather then 1-2 minutes.

Papers vary, image colour gets colder with age, shifts may not be a big as you expect etc

Ian

Ian: what is the purpose of the sodium carbonate? I have been using a simple Bz solution for cold tones (from the Darkroom Cookbook, I believe); 30 ml seems to give good results. Does the carbonate enhance the cold tones?
Thanks,
Dan

Dan, I think it's just a more stable solution.

However increasing the alkali in a developer and making it faster working also helps produce colder tones.

Ian

Sounds good. Now I know what to order.

So there's nothing special about Ilford Multigrade developer that you know of that would prevent this from working? I've done some searches on Multigrade dev, but couldn't really find much about it one way or the other.

Tim, you need to try it. The main problem with Multigrade developer is it's PQ based, and Phenidone (or Dimezone) is warmer working than Metol. There's too many variables to predict just how warm or cold toned a paper/developer combination will be particularly in respect to Neutral/Cold tones.

When I'm next back in the UK I'll do some testing to see just how cold toned I can get with some developer/paper combinations.

Ian

Understood. Off to find a decent scale...