Ilford Hypam Fixer and “Hypo” clearing agent.

[PeterDendrinos]

I have used Kodak Fixer over the years, and the hypo clearing agent following to aid in wash times, for both film and FB paper. Perhaps 2 years ago I switched to Ilford Hypam Fixer. I find it much easier to work with as it’s already in liquid form. However I never changed my method of processing. I continued to use the Kodak Hypo Clearing Agent.



In reading the spec sheet for the Hypam recently, I noticed that it indicates that it does not contain “Sodium Thiosulphate (Hypo)”, but rather is made up of “Ammonium Thiosulphate”.



Does this mean that there would be no benefit to using the Hypo clearing agent? I note two points here, one: The fact sheet for Hypam mentions using Ilford Washaid for FB Paper. And two; Ilford Washaid is stated to be “a hypo-eliminator formulated to aid the efficient removal of the thiosulphate byproducts of fixation by ion exchange”



I am a bit confused here about the term Hypo I guess. Any help in clarifying this would be greatly appreciated.



Thanks

Pete

 

[Ole]

"Hypo" is an abbreviation of "hyposulfite", which again is an obsolete term for thiosulfate. ANY thiosulfate, not just the sodium salt.

In photographic usage "hypo" has been used as a synonym for sodium thiosulfate...

And Kodak's "Hypo Clearing Agent" is sometimes confused with "hypo", with predictable results.

Personally I've never used HCA, and never felt (or seen) the need for it.

 

[ann]

I am sure some others will speak up to explain the chemical side of this question; however, what i do know is that Ammonium Thiosulphate is considered to be rapid fixer, which reduces the time factor for fixing.

We have been using Ilord's recommendations for fixing film for many years without any diffiuculties with the film. They, (Ilford) recommend not using a HCA with film .

With the use of fiber papers using a HCA is considered a help with the reduction of washing times. With RC papers it seems to be considered a waste of money.,

The term Hypo, is an old one with a general meaning of fixer.

 

[Lee Shively]

Kodak HCA does help with reducing washing times for fiber paper when using rapid fixer. I don't think the brand or type of rapid fixer matters much.

 

[George Papantoniou]

Hi Pete.

I agree that you don't have to use HCA with film (and RC paper, of course). It's only useful to reduce washing times with FB paper.

It'll work with ammonium thiosulphate, so don't worry about using it with Hypam.

Ilford reccomends photographers to use rapid fixer (Ammonium thiosulphate) in order to reduce fixing times, resulting to reduced infiltration of the chemical in the paper's fiber base (you see, the shortest the paper stays in the fix, the less the fix gets absorbed). This way, it's easier to get it out (wash it) and you can succeed to have archival processing with less water waste. If I'm not mistaken, Ilford has some info (a PDF) on their archival processing sequence on their website...

I actually use rapid fixer (amm-thio) since I began serious printing (it's almost 20 years now, I only use FB) and never had problems. I once had my prints tested for residual "hypo" and the result was great (zero...). Those prints were not treated in HCA...