Topic: Salt Fix

[Bryan]

I've been thinking about trying Caffenol for some time now but when Reinhold mentioned fixing with salt I just had to try that.  I decided to do an experiment since it was my first time attempting Caffenol.  I took two identical shots with my Crown Graphic using Kodak Super-XX film, expired in 1980.  The shots were both metered as 25 ISO, red filter.  Both sheets were developed in Caffenol C-L/S and semi-stand developed for 70 minutes.  The following link is where I got the recipe and the agitation schedule.  It's the same recipe that is found in the "Caffenol Cookbook" with salt (10g of iodized table salt) instead of Potassium Bromide.

http://www.largeformat-caffenol.com/p/recipes.html

One photo was fixed in Photographers' Formulary TP-5 Archival Rapid Fixer and the other was fixed in salt.  From reading Reinhold's blog about his tests with using salt as a fixer I mixed up 225g of iodized table salt into 750ml of distilled water (equivalent to 300g salt in 1L).  It takes a lot of stirring to get that much salt dissolved, that's why I used distilled water, I figured that may help it dissolve.  After adding the salt solution to the film I agitated it every now and then for the next 48 hours.  The agitation was not on a regular schedule, just whenever I happened by and remembered.  Usually I did 30 agitations then went about my business.  I did not wake up in the middle of the night to agitate but I did come home from work to walk the dogs at lunch one day so I agitated then. 

The biggest difference that I can see from the two negatives is the salt did not wash the coffee stains off as well as the TP-5 fix.  Otherwise I'm happy with the result.  The reason I wanted to try this is to have a way to develop film when I'm working on the road.  I can get everything I need at the grocery store without having to smuggle hazardous chemicals in my luggage.

This is the photo that was fixed with salt for 48 hours.

Clematis in Caffenol by Bryan Chernick, on Flickr

The next photo was fixed with TP-5 and following that is a comparison of the negatives.

[astrobeck]

beyond cool!
Is a salt fixer archival?  That always been my concern with using it.

One of the reasons I began using caffenol a few years back was because of the easy availability of the ingredients and that it leaves a little bit of stain on the negs and developed prints.
I have been using it exclusively for the past 2 years.
Looking forward to seeing more of this from you!
 

[Bryan]

Is a salt fixer archival?  That always been my concern with using it.

Thanks Becky.  From what I read on the internet, so it must be true, the negatives may fade over time.  I guess time will tell.  I have the two stored in a binder side by side so we'll see what happens.  I'll try to report back in a decade or two unless something happens sooner.  I would think like any photographic material it will last longer stored in a dark place.  I won't use the salt exclusively, especially since it takes 48 hours.

[jharr]

Pretty cool Bryan. Thanks for the side by side. It looks like the salt fix might result in the tiniest bit less contrast, unless you can attribute that to scanning or something else.

[Francois]

That is quite cool. I would have been afraid that the emulsion might lift off but it doesn't seem to be the case.

I can also see this as a good "in between" step where you fix with salt while on the road and then re-fix with real fixer when back home. Or something like that.

[imagesfrugales]

Great and thanks a lot for the report, Bryan.

I also noticed that Caffenol with salt as restrainer already gives a slightly yellow-brown tint, especially using -C-L version with less vit-c. More vit-c -> less stain after my experiance. Coffee solo always makes much more stain, but I don't like it.

Archival: I have (of course) no stressable knowledge about archival safety. But good sense doesn't tell me it's not. If you fix properly, meaning at least for the double clearing time, and rinse properly, why shouldn't it be equally archival? After some hours you surely can fix under light and inspect the negs by sight to determine the clearing time. That's most important imho to get clean fixings, especially with salt. But that's only guessing of course. At least I can tell, that re-exposing and a following forced development of a blank part of the salt fixed neg doesn't give any noticeable blackening at all. That's a very good sign imho. BTW, increasing the temperature reduces the fixing time very much. You decide how much you want to cook your films. But 38 °C is not prob for color films, so I guess it will be save also for most bw films. Increasing the temp will also help a lot to dilute the big amount of salt.

Maybe not all films work well with a salt fix. E.g. TMaxes, which are already delicate to fix in regular fixer, seem to work bad with a salt fixer. So you should test every film you work with before you ruin important negs.

[Bryan]

Reinhold, I would like to test it with other film like Ilford Delta or FP-5.  Does adding more vitamin C affect anything else that I should worry about?  I'm leaving town soon but won't be taking this show on the road this time so it may be a while before I can run any more tests.  I do have a project in Nevada later this summer that would be perfect to try this on. 

[imagesfrugales]

Does adding more vitamin C affect anything else that I should worry about? 

Yes, coffee and vit-c are rather acidic, and soda of course is alkaline. All 3 agents affect the pH and therefore the developers activity.  The (rs) versions of my recipes work fine because the pH is reduced but still high enough for less but sufficient development. Salt or bromide can be varied easily because they don't affect the pH.

[Jack Johnson]

That is quite cool. I would have been afraid that the emulsion might lift off but it doesn't seem to be the case.

I agree, and had the same worry. So cool that you tried it out, Bryan! And thanks for the tip, Reinhold!

[imagesfrugales]

And thanks for the tip, Reinhold!

My pleasure. I first denied a salt fix could work, I tried it with less salt. Then Henrique came and teached us how it works. E.g. here:
http://caffenolcolor.blogspot.de/2012/03/alternative-to-fixer-bath.html
http://caffenolcolor.blogspot.de/2012/04/making-better-salt-fixer.html

[Bryan]

Thanks to Typhoon Dolphin for delaying my project on Rota I had some time to do another test before I leave town.  This time I wanted to see how well the salt fix works with Delta 100 since that is a film I will likely be shooting more of.  I did everything the same as before and the results look very similar.  The only issue I found was a hole in the emulsion (see closeup below).  I'm not sure how this would happen, the negative does not seem thin but I'm no expert on that with my limited developing skills.  I have a theory, a piece of un-dissolved salt stuck to it and burned a hole.  Or somehow I nicked it.  This time I saved the salt solution for future developing, that way I will know it's fully dissolved.

Hosta by Bryan Chernick, on Flickr

[jharr]

Nice photo Bryan. It looks like there is another artifact at about 9:00 maybe 1/5 of the way in from the left edge. There is a blob of some sort on there (unless there was a blob on the actual leaf). Still, I think the fix is a good option for travel or for those who are enviro-conscious. Keep up the good work.

[Bryan]

Thanks James, I think that artifact is where a bug munched on the leaf.  The one I pointed out really jumped out at me when I held the negative up to a light, clearly no emulsion in that spot.

[Francois]

It could be the temperature there too low so the salt precipitated out of solution...
Or fixing for 2 days is too long...
Or it was a defect on the emulsion that was there from the start...

[Bryan]

It could be the temperature there too low so the salt precipitated out of solution...
Or fixing for 2 days is too long...
Or it was a defect on the emulsion that was there from the start...

I may be fixing for too long.  I have seen others on Flickr that fix with salt for much less time, 3 to 7 hours.  They are using warmer water which would not be practical for me if I'm doing it in a hotel room.  The salt is precipitating out, I checked the bottle of salt water that I saved from this last photo and there is salt in the bottom.  With more tests I may be able to refine the time and mixture but I'm pretty happy with the results so far.  That one hole was easy to fix in Photoshop.  We'll see if I get more holes in the future.

[Francois]

One thing could do is saturate the heck out of the solution, let it sediment and then decant the clear water before putting the film in.
Or filter it using a cotton ball and a funnel.

[Jack Johnson]

I may be fixing for too long.  I have seen others on Flickr that fix with salt for much less time, 3 to 7 hours.  They are using warmer water which would not be practical for me if I'm doing it in a hotel room.

I keep thinking of the monobath scenario where it's a horse race between the developer and the fixer, and with a salt fix that horse would always lose, which is exactly what you'd want in a monobath. If you could do a suitably weak developer and do it in one pass, maybe it would be gentler on the emulsion. Or, if the salt is acting also acting as a restrainer in my hypothetical monobath, maybe the horse race doesn't have to be very close. Way out of my league on that front, but it's fun to think about.

You hear these apocryphal stories about people using just about anything as a developer back in the day. I've started fantasizing that you could do something crazy like Diet Coke and Mortons in a spiral tank for a day, Mortons solo for another day, rinse, and voila.

But, for the topic at hand, in a hotel room, if you have a little coffee pot maybe you could heat the water to increase the salt saturation, let it cool, use the coffee filter to filter out the precipitate, and you might end up at max saturation for the resulting water temp.

[Bryan]

Funny you should mention the hotel coffee pots Jack, I was thinking how I could use that in my developing.  I don't drink coffee so I was thinking I could use the free coffee they supply but I don't think it's instant.  I may try your salt idea. 

[hjtsousa]

Hi, everybody!

Glad to join this forum. Thanks to my friend Reinhold G. who sent me a link to this thread. In fact, I re-discovered salt as fixer, searching the internet for old photo processes, namely daguerreotypes. Before the discovery of thiosulfates (once called hyposulfites) by Sir Herschell, salt was used to fix the daguerreotypes in a warm and concentrated solution. But it became a myth and I just succeeded to put it working again by using a solution of at least 300g/liter and some temperature, 35ºC is OK, it will not damage your film and you may reach acceptables fixing times of 90 minutes, or more, depending on the film.

But, thanks God, there are better fixers than salt. Another alternative is Ammonia, yes, it works. And all other thiosulfates other than the well known Sodium and Ammonium Thiosulfates. Also Potassium, Calcium and Magnesium Thiosulfates will fix and quickly your films or papers. Many fertilizers are using these thiosulfates, so they will be cheap enough, I hope.

PS - I am the Henrique mentioned above by Reinhold!

[Bryan]

Welcome Henrique, I look forward to your contributions to the forum!  That would be interesting if an off-the-shelf fertilizer would work as a fixer.  I like the salt because it's less toxic and I'm not very concerned about the time it takes.

[imagesfrugales]

Nice to see you here, Henrique, and a very warm welcome.

[hjtsousa]

Thank you, Bryan, thank you Reinhold for the welcome wishes!
About toxicity to human, Bryan, yes, no problem with salt. Also it is available everywhere and is a cheap stuff.
I had played with salt as fixer some time ago and at the time I was using Fomapan and Shangai films. They go very fast, compared to TMax as Reinhold already pointed. I understand you about having no rush with the process. But, also like Reinhold said, after one hour you may open the tank and control the clearing process. After clearing, double the time and it should be fine.
Really important is that it must be a saturated salt solution, it makes a big difference. I had a battery densitometer to check the concentration and the mark I used was beginning of «full charge».
Regards,
Henrique

[Francois]

Welcome Henrique!
Its nice to have some different insight

[hjtsousa]

Welcome Henrique!
Its nice to have some different insight

Thanks a lot, François! Only dead fish follow the water stream!

[Henrique]

Hello everybody!

After some people showed interest in this subject, I made an experiment where I added some drops of Sodium Hypochloride to the salt fixer. In this way it was possible to reduce the fixing time to 1/3 and to fix a stripe of TMax in about 12 hours what, with salt alone, was not possible, even in 48h or more.
I used household ammonia at less than 5% concentration and from it only 2ml/liter, about 40 drops.

[jharr]

Resurrecting this topic because I have a related question. Has anyone tried this with Harman direct positive paper? How about regular RC paper? I figure I'll give it a go, but it would be nice if someone knows that there's no way it will work. That could save me some time.

[Francois]

I think the final answer is probably "we have no idea"...
I could make a strong salt solution in a dark can, put a piece of paper in it for a day and develop after to see if there is any silver left...