Gevaert 504

[piticu]

Does anybody has a different formula for this reducer?

Mine is from “Gevaert manual of photography”, fifth ed rev, 1962 and it says:

Ammonium persulphate 20grams
Sulphuric acid conc. 10drops
Water to make 1liter​

Any help will be much appreciated.

 

[Ian Grant]

That's the correct fomula for the Gevaert Persuphate bleach, it's the same in earlier editions. Can't check the 1st 1938 that must be on my shelf in Turkey.

Ian

 

[piticu]

Thanks a lot Ian. It will be correct to say that 10drops equal 2.5 mililiters?

 

[Ian Grant]

I've found I do have the 1st edition here taht gives volumes in UK avoirdupois, I'll try and convert accurately later when I have more time. There is a conversion for drops to actual volume, but it's best left as drops.

Ian

 

[piticu]

I've found I do have the 1st edition here taht gives volumes in UK avoirdupois, I'll try and convert accurately later when I have more time.

Many thanks again Ian. Looking forward