Hypo Clear

[jeroldharter]

I am just wondering...

I am used to using Heico PermaWash. I like the liquid vs. the solid of Kodak Hypoclear. Easy dilution etc. However, the availability seems to be waning and the cost rising. In searching various vendors, Freestyle seems to have the best selection of similar products which range in price. Their Arista Hypo Clear "equivalent" product is liquid and very inexpensive.

Why should I not use that?

Does anything really distinguish one liquid product over another? Thanks.

 

[Ian Grant]

Using Sodium Sulphite solution is even cheaper still and just as effective.

Ian

 

[PVia]

Ian...what's the dilution again? I know I saw it somewhere a while ago...

Isn't there anything else in HC besides Sodium Sulfite?

 

[Ian Grant]

A 2% solution is fine. You can add some Sodium Metabisulphite if you want but it's not necessary.

Typically:

Sodium Sulphite (anhyd) 200 gms
(Sodium Metabisulphite 50 gms)
Water to 1 litre

To use Dilute 1+9

 

[David A. Goldfarb]

Permawash (B&H still sells it) contains sodium sulfite and ammonium sulfite and claims to be more effective than a straight sodium sulfite solution in reducing wash times. The instructions for double weight FB papers are 2 min rinse/2 min Permawash/2 min final wash. I haven't actually made a comparison test, but can anyone verify or debunk that?

 

[Ian Grant]

Agfa recommended a Sodium Carbonate bath for clearing Hypo from their Fibre based papers. Others suggest Sulphite with a small amount of Carbonate. These aren't hypo eliminating baths, these hypo clearing baths are only an aid to shortening washing.

Plain Sulphite is sufficient.

Ian

 

[David A. Goldfarb]

I realize that, but can one kind of wash aid reduce wash times more than another type of wash aid? I realize that I should be doing a residual hypo test to figure this all out, but if, say, straight sulfite will get me a 30 min. wash time and PermaWash gets a 3 min. wash time, then that's significant.

Just to confuse matters, I usually use TF-4, which should require a shorter wash time than an acid fixer, so this gives me another reason to do a real test one of these days.

 

[Ray Rogers]

Since we are already talking about HC,

Can someone tell me why it is said that the useful life of a plain sulfite HC bath is very short?

Ian,
What is the Meta there to do?

???

 

[Ian Grant]

The Sodium Metabisulphite lowers the pH, making the solution slightly acidic. Steve Anchell in the DCB 2nd Ed states it can be left out when used with prints, but helps prevent emulsion softening with films. (3rd Edition due out very soo states exactly the same). Ammonium Sulphite is used for the same reason.

I guess working with a relatively weak solution there's a risk of the Sulpite breaking down to form sulphate which would be far less effective. The length of the rinse/wash after fixing will also have a large effect on the capacity of the HC.

The reduction in wash times will be much the same with any Sulphite based Hypo Clearing agent, but some manufacturers will be more cautious on the actual times they recommend.

Ian

 

[MikeSeb]

Jerold, another approach would be to switch to a neutral or alkaline fixer, like Formulary TF-4, which would eliminate the need for hypo clear entirely.

 

[Ian Grant]

It does actually eliminate the need for Hypo clear, because you don't need to use Hypo Clear after any fixer. Even after a neutral or alkaline fixer a Hypo Clear, which really should be called a wash-aid, will help reduce the washing times with fibre based papers.

Ian

 

[Mahler_one]

You beat me to it Mike...I was wondering the same thing with reference to Formulary Rapid Fixer. Anyone know? I can call the Formulary people tomorrow to inquire.

Edwin

 

[jeroldharter]

Thank you all for the helpful and informative posts.

My conclusions so far are that:

if I continue with a commercial product, then they are all about the same so just buy the cheapest.

if I make my own, buy some anhydrous sodium sulfate and mix the stock as I need it. If I do that and use the 200 g per liter of stock solution, must I weigh it with a scales or is there a common measure (i.e. 1/2 cup) or similar that I could use that would be close enough?

if I switch to TF-4, then I don't need to bother with a wash aid at all? I am not too familiar with TF-4 as an alkaline fixer. Does that mean that I should avaoid an acid stop bath as well?

 

[Ian Grant]

if I make my own, buy some anhydrous sodium sulfate and mix the stock as I need it. If I do that and use the 200 g per liter of stock solution, must I weigh it with a scales or is there a common measure (i.e. 1/2 cup) or similar that I could use that would be close enough?

if I switch to TF-4, then I don't need to bother with a wash aid at all? I am not too familiar with TF-4 as an alkaline fixer. Does that mean that I should avaoid an acid stop bath as well?

I'm sure that there's teaspoon weight in the DCB, but use SULPHITE not sulphate they are very different.

Most modern fixers like Ilford rapid fix or Hypam are only very mildly acidic and using an alkali or neutral fixer is not so different. It's the acid fixers & acid hardening fixers that are best avoided.

Ian

 

[jeroldharter]

...use SULPHITE not sulphate they are very different...

Ian

Yes. I made a typo. I use Hypam currently.

 

[ic-racer]

Personally, I treat recommendations on fixer, wash and wash aid like recommendations on exposure index and developing times. Just a guideline but not necessarily what's going to work in my darkroom.

I suspect most questions on fixing and washing could be better answered with a personal ST-1 and HT-2 test.

 

[jeroldharter]

I did some quick arithmetic. Using the Sodium Sulfite from Photographers Formulary, the cost of making homemade wash aid is about 50% the cost of using the cheapest commercial wash aid.

I wonder though how long a container of the anhydrous sodium sulfite would last before humidity had an adverse effect? I know the answer is "it depends" but for those who make their own, does humidity ever matter in practice or do you use up the container and move the the next without problem?

 

[David A. Goldfarb]

Sodium sulfite is even cheaper if you buy it in larger quantities from The Chemistry Store. They also sell a few other photographically useful chemicals like sodium thiosulfate and items that have non-photographic uses like sodium hydroxide, potassium permanganate, and such. They don't seem to have any developing agents. http://www.thechemistrystore.com/

 

[dancqu]

Most modern fixers like Ilford rapid fix or Hypam are only
very mildly acidic and using an alkali or neutral fixer is not
so different. It's the acid fixers & acid hardening fixers that
are best avoided. Ian

IIRC the ph of those two Ilford fixers runs 5.5. They are
without hardener. So I wonder, why are they the least
bit acidic? Off hand the only reason that comes to
mind is the ubiquitous preceeding acid stop and
Ilford's wish to maintain, for some reason,
the acidity of the fixer. Dan

 

[Ray Rogers]

It's the acid fixers & acid hardening fixers that are best avoided.

Ian

and thats because... ?

 

[dancqu]

Agfa recommended a Sodium Carbonate bath for clearing
Hypo from their Fibre based papers.

Others suggest Sulphite with a small
amount of Carbonate. Ian

Carbonate rates well as a hypo clearing agent and
has the advantage of not oxidizing. The problem with
it though is the lack of any quantitative data. How
long in what strenght and what about capacity?

How about carbonated fixer. B. Troop has himself
stated that the higher the ph, up to 10.5, the
more quickly the paper will wash. I'd suppose
that would apply as well to an immediately
following HCA. Dan

 

[Lowell Huff]

Hello Mike:
The pH of the fixer is not relavant to the use of a clearing agent. The purpose of clearing agent is to add ions to the wash solution to "bump" out the residual impurities from processing. Since this is a physical not a chemical reaction, more ions speeds the process. What ever the case, more than ten minutes of washing is a waste of your life time.