Sodium Thiosulfate "Plain Fixer" question
Hi All,
last week I posted a question about the mix of Sodium Thiosulfate "Plain Fixer" to water to make a plain fixer. I had planned to use it, with the addition of sodium bisulfite in fix one, as a two step fix process.
I mixed 16oz of the Sodium Thiosulfate to 2 liters of water at around 90'. It really did not want to dissolve and eventually did dissolve but I ended up with a very thick liquid that had a greasy feel to it. I did not want to chance a print in it so I swapped back to reqular rapid fixer for the rest of the session with no issues.
Did i mix this wrong? I bought regular Sodium Thiosulfate from e bay listed as for photography. Was the mix i listed above for the concentrate and should I make a working solution from that?
Should I give all of this up and admit defeat? :)
thanks
david
Re: Sodium Thiosulfate "Plain Fixer" question
When I asked about how to do Sodium Thiosulfate "Plain Fixer" of the folks from Photographers Formulary, they told me:
You want to go by weight so use 15 grams to 100 ml of water to make a 15% solution so 150 grams to 1000ml
So, for 2 liters of 15%, you'd use 300g by weight.
Richard
Re: Sodium Thiosulfate "Plain Fixer" question
Well, 16oz is roughly 454gm, so in 2 liters that would be about a 22.7% solution.
You're not that far above the desired 15%.
I don't understand why it would be "thick and greasy". Are you sure it was the right stuff?
- Leigh
Re: Sodium Thiosulfate "Plain Fixer" question
What you want is sodium thiosulfate pentahydrate rice crystals. The best source I've found for this is the Chemistry Store. The 50 lb. bag is the best value. 16 oz. (two cups) dry measure of this per 1/2 gallon of water at 90°F will give you the fixer you want. It goes into solution quite easily.
Either your ebay source gave you some other chemical or it's not prismatic rice crystals. I've used hundreds of pounds of this chemical from the Chemistry Store and it makes a great alkaline fixer. I promise. You can't go wrong.
Re: Sodium Thiosulfate "Plain Fixer" question
Thsi is what I bought:
http://cgi.ebay.com/ws/eBayISAPI.dll...=STRK:MEWNX:IT
Specifically stated to be:
Sodium Thiosulfate Pentahydrate
Crystals
When I say thick I am not talking maply syrup thick...it was just much thicker than any fixer I have ever seen and it did have a greasy feel to it and was sort of hard to wash off.
Funny enough I bought most of my other stuff at the chemistry store! Maybe I messed up here!
Re: Sodium Thiosulfate "Plain Fixer" question
Quote:
Originally Posted by
atlcruiser
The Chemistry store is cheaper, even in small quantities. ($2.50/lb. for 2 lb.) I don't know about the greasy feel, since I always have a glove on when I put my hands in it, but it's not particularly thick when mixed.
The picture looks like the right stuff. I would've tried fixing a print with it. In any case 1 lb. certainly won't last very long. Buy 9 lbs. or so and give it another try.
Re: Sodium Thiosulfate "Plain Fixer" question
Did you use hot water to start?
Re: Sodium Thiosulfate "Plain Fixer" question
A strong solution of thiosulfate is a bit viscous. Nothing wrong with it at all.
Re: Sodium Thiosulfate "Plain Fixer" question
Quote:
Originally Posted by
Richard Rankin
When I asked about how to do Sodium Thiosulfate "Plain Fixer" of the folks from Photographers Formulary, they told me:
You want to go by weight so use 15 grams to 100 ml of water to make a 15% solution so 150 grams to 1000ml
So, for 2 liters of 15%, you'd use 300g by weight.
Richard
exactly -
water is 1g = 1cc(ml)
Re: Sodium Thiosulfate "Plain Fixer" question
Thanks all...I did mix it a bit strong at 16oz to 2l of water. I will trash what i have and mix again.
I did mix it at about 90'. I think all is well and maybe I was a bit slow on the uptake