View Full Version : Making sodium sulfite clearing mixture for Type 55

25-Feb-2005, 13:00
Can anyone tell me how to go about making the 18% sodium sulfite clearing bath for Type 55 without a scale? I have no way to measure the dry mixture by weight, but I know - in school - that I made it by measuring by volume. Also, is the mixture safe to dispose of down the drain? Thank you.

Steve Hamley
25-Feb-2005, 13:42

The percentage isn't all that critical. You'll find that it isn't very easy to get the weighed amount for an 18% solution to dissolve (involves a lot of stirring). So if you just dissolve all you can in a reasonable amount of time in water you just removed from boiling , you should be close enough.

They put small amounts of sodium sulfite in food as a preservative, so yes you can pour it down the drain.


Gem Singer
25-Feb-2005, 15:37
Hi Todd,

Formerly, I was purchasing sodium sulphite in 180gm. packets from Artcraft Chemicals. Mike, the owner of Artcraft, weighed it out and put it into individual plastic packets. I dissolved the entire packet in one liter of water to make an 18% solution. I stored the solution in a one liter Rubbermaid bottle and re-used it until it became too dirty to use. I filtered it through a coffee filter once in a while, and it lasted for a long time.

That was the way I used to do it. Now, I use liquid Heico Permawash, 25ml. in a liter of water. It is more convenient and cleaner working than dissolving the powder in water. Either solution can be re-used and disposed down the drain when it is used up. However, I usually use the Permawash solution as a one-shot clearing agent, and toss it out after I'm finished with it.

25-Feb-2005, 15:42
A 1/4 cup weight in right at 100g, an 1/8 cup at 50g. These are leveled off measures. Just shy of a 1/2 cup should be about right.

Tom Westbrook
25-Feb-2005, 16:33
<p class="story_text">Polaroid's manual (http://www.polaroid.com/service/filmdatasheets/4_5/55fds.pdf" target="_blank) for Type 55 says to dissolve 1 lb. of Sodium Sulfite in 2 liters of water. That's just to make it easy for most people to remember, but that's more like a 22% solution and is a waste of good Na<sub>2</sub>SO<sub>3</sub>. The following was taken from Ansel Adam's book on Polaroid films, but if you notice that 180 divided into 1000 is 18% of the total volume, it's pretty easy to remember this way.

<table width="433" border="1" cellpadding="2" summary="Solution used for clearing Polaroid Type 55 film.">
18% Sodium Sulfite Solution for Type 55
<td width="293"><div align="left">Water, 27&deg;C-32&deg;C </div></td>
<td width="120"><div align="left">750ml</div></td>
<td width="293"><div align="left">Sodium Sulfite (anhydrous or desiccated) </div></td>
<td width="120"><div align="left">180g (6.3 oz.)</div></td>
<td width="293"><div align="left">Water to make </div></td>
<td width="120"><div align="left">1000ml</div></td>

25-Feb-2005, 17:45
Speaking of sodium sulfite, where can you buy bulk quantities of the stuff?

Gem Singer
25-Feb-2005, 18:20
Ken M,

Read my post above. Call Mike at Artcraft Chemicals (www.artcraftchemicals.com (http://www.artcraftchemicals.com)). He accepts phone orders on weekends.

Tom Westbrook
25-Feb-2005, 18:45
Photographer's Formulary sells it in bulk, too. http://www.photoformulary.com

25-Feb-2005, 19:42
I buy most of my stuff from Artcraft as well, but hypo and sodium sulfite can always be purchased locally if you live in a big enough town for a fraction of any photo chem dealer, and no shipping.
Look in your yellow pages for commerical pool suppliers or commerical boiler suppliers. Sodium sulfite is used as an oxygen scavanger in big boiler units so they dont rust out, it essensially does the same thing in developer, thats why its a preservitive.
I bought a 50 lb bag for around 75.00$us.
Look for somewhere on the train tracks, these places get stuff by the boxcar load. I have never had any luck talking to the front office people, but there always seems to be a guy in the back who knows everything, you must find him.
You may have to jump through a few hoops to buy from wholesale sources like this, and they sometimes want to make sure your not making drugs or bombs or something. And bring a checkbook, using cash or credit cards can be kind of akward, these folk are use to selling by the ton to established accounts. One place even sold me a 50lb bag of hypo, net 30 days!

26-Feb-2005, 06:38
Mixing is not that critical Todd. You'll be able to tell very quick if you used too little because it won't clear very easily. But my experince has been just fine when I mix it at about a tablespoon to a pint or less of water. Type 55 clears almost instantly. I ususaly kept my 55's in a zip lock after shotting to keep them moist. Saved a little time in clearing and getting the paper off.
Good luck and happy shooting.

Gem Singer
26-Feb-2005, 12:26

With a 50 pound bag of Sodium Sulphite, you could produce your own brand of hypo clearing agent, bottle it, and distribute it to all of the remaining camera shops in the USA that still handle darkroom equipment. You could compete with Permawash, Orbit Wash, Ilford Wash Aid, etc.