Hypo or not?

[Asha]

I will soon be ordering some fixer ( amongst other items) for film / paper.

I've used Ilford Rapid Fixer for years with no probs so I see little reason to change, however I see that there is a HYPO version available.

I don't understand much about the differences …something about adding hardener isn't possible with the standard fixer, not that i know why one would add a hardener anyway ( I need to read more! lol)

So what do you guys recommend.....Stay with what I know or go for Hypo ?

 

[dmb]

Hypo - is a short name for sodium thiosulphate aka "hyposulfite of soda". This was the original fixer described by Sir John F. W. Herschel in 1839, and solved Fox Talbot's problem of his salted paper negatives and prints fading, previously he was stabilizing by soaking in very strong salt solution. When gelatine coated plates were introduced 'alum' (aluminium sulphate) was added to fixer to harden the emulsion to stop it lifting off the plates during fixing. This practice of using hardening fixer carried on into the film era. The downside of hardening was that it required very long wash times to remove remaining silver salts and hypo from films. Modern film emulsions are tougher than those of the past. Rapid fixers using ammonium thiosulphate are more modern fixers and as they work more quickly the film emulsion does not need to be hardened while fixing and so washes more quickly too. It is possible to add hardener to a rapid fixer but only when developing at high temperatures (>30 C), or when rapid drying needed or using roller transport processors.

 

[Kevin Allan]

My approach to buying fixer is to get the cheapest I can find, which will always be in a 5Litre bottle rather than the little ones. That makes 20-50 litres depending on dilution. It may go off before I finish it but it's still a lot cheaper than buying smaller bottles. I may be wrong but I'm reluctant to believe that there's any functional difference between brands. The current bottle is Fotospeed FX30, the one before that was made by Agfa.

 

[Asha]

My approach to buying fixer is to get the cheapest I can find, which will always be in a 5Litre bottle rather than the little ones. That makes 20-50 litres depending on dilution. It may go off before I finish it but it's still a lot cheaper than buying smaller bottles. I may be wrong but I'm reluctant to believe that there's any functional difference between brands. The current bottle is Fotospeed FX30, the one before that was made by Agfa.

My last container of ilford rapid fixer was of 5 litres bought before I moved from Nice to Sospel in 2014. !!
I’ve only just started to have problems with its performance.
The last batch made last week needed nearly 10mins to clear the film completely but it still worked!
The dregs of about 500ml concentrate left in the container don’t look good and have a lot of white sediment so will be going in the bin.
I am very impressed at how long the concentrate lasted though.
I will be buying 5 liters again this time not least of all as I will get through more chems due to my adventures into wet printing.