How Much Metol in Pyrocat?

Hello,

I'd like to mix Pyrocat-M, but there's something I don't understand. The formula calls for 2.5 grams of metol. However, Sandy King says here that in Pyrocat-HD the phenidone can be replaced with 25g of metol.
Admittedly, Pyrocat-M has no potassium bromide, but somehow I don't think that potassium bromide alone could account for such a great difference in the amount of metol.
So, how much metol should I use?

Another question: is the shelf life of Pyrocat-M the same as that of Pyrocat-HD? Can I expect solution A (mixed in water) to last up to a year in a partially full glass bottle?

Thank you.

hello,

i've tested both levels out of fear and the lower amount is correct. from my understanding the pot. bromide is a carry over from the phenidone version and Mr King has omitted them from all the recipes. at this link you can find the lastest on the pyrocat developers. i mix up 50ml at a time so that i don't have to worry about stock A failing so i can't comment on the longetivity of the solution. hope this helps.

Thank you.

The Pyrocat-M formula, which calls for 2.5 grams of metol, is also for one liter.

VladSoare said:

The Pyrocat-M formula, which calls for 2.5 grams of metol, is also for one liter.

Click to expand...

Noticed it and deleted my message within 5 min. Unfortunately, you were even faster with your reply.

skahde said:

Noticed it and deleted my message within 5 min. Unfortunately, you were even faster with your reply.

Click to expand...

So that's why I couldn't quote your post, thought APUG had got a glitch


Sandy King changed the level of Metol from his original 25g/litre to 2.5g some time ago.

So both are technically correct, but his current thinking is that 2.5g is better.

Ian

Noticed it and deleted my message within 5 min. Unfortunately, you were even faster with your reply.

Click to expand...

Yup. Speedy is my middle name.
I'm subscribed to this thread and I receive an e-mail whenever a new reply has been posted. And Google Talk alerts me of new e-mails in real time.

Thanks Ian, it's all clear now. I'll go for the 2.5 version.