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JOZO brand?
I think that comes from Holland, they're selling it here.
Posted 12 months ago.
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In cooking, I have come to think of a small salt addition as equivalent to adding a wetting agent in photo chemistry. e.g: I use a decoction of ginger root for reduction of dizziness (I drink it!). When I create the decoction I add a small amount of "NaCl" and have a stronger brew come out (which then is to be diluted before drinking, a bit bitter as it is).
Might it be possible to have the above "Salt effect" with wetting agent too? Might be something to try as time allows and there is opportunity.
Posted 12 months ago.
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Cool I may have more chance of getting that :-) the potassium bromide was not going to happen
Posted 12 months ago.
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The restraining effect is made by the iodates, therefore one has to use iodized salt. I wouldn't use iodized and fluoridized salt, as the fluorides may cause more problems than benefits.
Salt effect with wetting agent??? Never say never but sounds very strange and wetting agent (detergent) imho has not to be in any developer at all. But don't quote me about that, esoteric formulas aren't my cup of tea at all.
BTW I'm not the first to use iodates as a restrainer and the effect is well known in literature since many years but not very often used. For ready made commercial developers pot. bromide is the choice. But for us homebrewers it can be an alternative if the bromide is not available easily. As a starting point you may use the tenfold amount of the recommended pot. bromide, f.e. 10 g/l iodized salt instead of 1 g/l pot. bromide.
Originally posted 12 months ago.
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imagesfrugales edited this topic 12 months ago.
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Hi Reinhold I have a question here:
Iodized salt is a mixture between NaCl (common table salt) and NaI or KI, I'm not familiar with what different brands place into this.
Since placing 10 g per litre ogf this into the developer, most likely we then place about 8 gram of NaCl in. (generally speaking the mixture is rarely more than 20% KI or NaI)
Have your info-source on this anything to say of how this amount of NaCl in the developer affects how the rest of the developer works?
Posted 12 months ago.
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Now I have checked the facts:
I have access to two types of table salt that contains Iodine:
Both JOZO brand from AkzoNobel out of Denmark.
First is known as HAVSALT (oceansalt) and is said to contain traces of "valuable elements". Since there is iodine dissolved in the ocean, there is a tiny little amount.
The other is known as JOZO salt - fint salt med jod (fine salt with iodide).
The label says antilumping additives E551 and E535 (will look that up after my trip to the bank) and Iodine (KI , potassium iodine) 0.5 mg / 100 gram.
That is 5mg per kilo or 0.005 gram per 1000 gram salt. (numbers corrected by Robbe K).
Or just 0.00005 gram into the solution if we add 10 gram salt per liter.....
Clearly this concentration is too low to have any substantial effect.
But there are 99.9995 gram of NaCl, sodium cloride.
We are talking HALIDES here, in film we have iodine, bromide and maybe cloride as silver-salts, these all reacts to light.
If theres any effect, my hunch is that cloride is the culprit!
I will be following Reinholds experiment here with great interest, because theori is worth zilch, if it works in practice..... we have to find another theory if thats the case as with all natural sciences....
Originally posted 12 months ago.
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hfandrep edited this topic 12 months ago.
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Oops, not Reinhold but ..
In "Photo Techniques" (Dr Chapman) is mentioned that Chlorides are perfect restrainers if there is AgCl in the emulsion (probably only for paper thus). The Iodo-Bromide emulsions should be restrained either (or both) by Bromides and Iodides. However for the Iodo-Bromide emulsion he estimates the restraining capability of Cl's at 1/200 compared with the Bromides - (the Iodides ar much stronger).
Some books mention Chlorides as silver-solvents.
Posted 12 months ago.
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0.5mg/100g = 5 mg/Kg , not ?
Posted 12 months ago.
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You're right, Robbe, I was too preoccupied with going to the bank lending a million!
Posted 12 months ago.
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Just for info, the modified Crawley FX-1 high acutance developer employs as restrainer 10 ml/liter of potassium iodide 0,001% (in weight) solution (50 ml in the original formulation).
It means 10 mg/liter in the mother solution, and 0,1 mg/liter in the working solution. (0,5 mg/liter in the original formulation). If the salt contains 5 mg/kg iodine (equivalent to about 6 if expressed as KI) , 10g of salt should contain about 0.06 mg of KI equivalent, very close to the FX-1 content. Moreover, there is a 1700 times larger quantity of chloride and an unknown quantity of bromides that also have some additional anti-fog effect.
Next time, I will experiment the addition of 10 g of iodized salt.
BTW: in the old good times when I could easily buy raw chemicals, I experimented the homemade FX-1 : excellent and very cheap !
Originally posted 12 months ago.
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stragatto edited this topic 12 months ago.
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What about a drop of tincture of iodine into the developer with no salt?
Posted 12 months ago.
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the elemental iodine is a strong oxidizer and it would destroy the developer !
Posted 12 months ago.
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Destroy it how fast? If using one shot this is most likely not a problem.
Posted 12 months ago.
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immediately:)
Posted 12 months ago.
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I have no facts teling this, just the empiric finding that a small amount of NaCl has about the same effect as wetting agent. i.e. salt is a "wetting agent" in cooking.
Now if "wetting" (reducing the surface tension) would be part of the practical effect of salt, one could try real wetting agent instead.
In theory, I'd expect wetting agent to open up access for other chemicals to enter the emulsion. If that is the effect in practice, is still to be found out.
Originally posted 12 months ago.
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Hannu E. K. edited this topic 12 months ago.
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but you can reduce the iodine to iodide by adding some fixer (thyosulphate) to a little quantity of tincture. The tincture is 7% elemental iodine plus 5% potassium iodide. According to the thyosulphate concentration of your fixer, you could calculate the quantity of fixer to add (better some small excess) and the quantity of tincture to dilute and the quantity of diluted solution to add to your brew. I think that is a lot more practical to try with the salt :)
Posted 12 months ago.
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Bingo thanks. Sorry but my brain is moving a little slow these days but my LED just came on. :-)
Posted 12 months ago.
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Excellent Stragatto, I like tha way you think.
Also thanx for the insight into FX-1, I think the massive excess of clorides would be the operating factor here - still looking forward to Reinhold's report on this!
Posted 12 months ago.
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@hfandrep: I am now retired and trying to forget that I was a chemist, but sometimes I still (unwillingly) think as a chemist :)
Posted 12 months ago.
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The salt I'm using is containing 0,0025 % potassium iodate (Kaliumjodat) = KIO3. So no iodide (KI) but who knows what is happening in the developer to the iodate. Iodide again is said to be a very strong restrainer in smallest amounts. Cloride is said to have absolutely no restraining effect, even in highest concentrations, on silveriode and silverbromide based emulsions like all film emulsions used today.
So as I don't kow what happens to the iodate but iodide is a strong restrainer and cloride most probably doesn't do anything, the iodate should be responsible for the restraining effect. But how much to use? The only useful way is try and error. Others did that try and error before like Rob and most probably some others, and my first trial with 20 g/l was way too much restraining but also not too far away from the possible optimum.
With FP4+ 6 g/l iodized salt was quite optimal and gave me fine negs with a completely clear film base, no fog at all. Done with Caffenol-C-M(RS) - reduced soda 40 g/l waterfree instead of 54 g/l). Of course the FP4+ wouldn't have needed any restrainer in an agitated Caffenol-C, but why not use a so cheap and commonly available one and get even better negs?
With HP5+ 8 g/l was a bit too little, remarkable fog but still very good usable negs. So I think about 10 - 12 g/l would be fine for the HP5+. But don't overdo the restraining. Fast films always have a higher base fog level than slower films. Done with standard Caffenol-C-L.
Since I use about 0.5 g/l pot. bomide compared to 6 g/l iodized salt for medium fast films, and 1 - 1.3 g/l pot. bromide compared to 10 - 12 g/l iodzed salt, the conclusion is to recommend about the tenfold amount of iodized salt compared to pot. bromide as a good starting point.
Provided your salt has the same iodate concentration. My fault was not to specify exactly which kind of salt I used. Sorry for that.
Cheers - Reinhold
Originally posted 12 months ago.
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imagesfrugales edited this topic 12 months ago.
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Thank you Reinhold, as usual you comes through with DATA.
One should think you're a chemist! :-))
Posted 12 months ago.
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I did some tests after buying 5g of KI at the pharmacy.
Without a starting point I used the same amount of a DDR developer that uses it in combination with Benzothiazole (same amount) : 4mg/L.
For PolypanF this imho is too much (I skipped the Benzo, i simply can not buy it).
[http://www.flickr.com/photos/32981029@N07/5716752168/]
I think it almost works like a lith developer - this very thin film imo does not need it an maybe some of the shadows are already gone.
But on Double X this amount worked fine :
users.telenet.be/bobkeppens/2011/KI01.jpg
(it was raining, so contrast was better than expected).
Cl's restrainers ?
This is a copy/paste from one of the fora :
" I did some very limited experiments recently. Sodium chloride does seems to
act as a restrainer, if you use enough of it, but the effects are
noticeably different than with potassium bromide. Its slight silver
solvent action (it is quite slight) may account for this. The grain seems
rather more point-like. You should compare results under a microscope (30X
will do) to understand its action. I don't know how it affects fog, but
there was no obvious difference vs. KBr in my limited tests. "
And the early Rodinal formulae also contained Cl's, because based on p-Aminophenol.hydrochloride. I simulated this with adding some KCl in my home brewed R09 (well kind of) - and the results were certainly not worse, but same remark is in the quote : the grains seem more point-shaped (? strange because the low amount of Cl's -- but I also started with metabisulphites as the formula published by Dr Andresen (1919 ?) i don't understand why the metabi's should give another result than the usual Ksulphites -- pH is adjusted ofcourse)
Rob
Originally posted 12 months ago.
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RobbeK edited this topic 12 months ago.
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@Reinhold: probably some very small quantity of vitamin C is oxidized by the iodate, which in turn is reduced to iodide.
3 C6H8O6 + KIO3 → 3 C6H6O6 + 3H2O + KI
(C6H6O6 = dehydroascorbic acid)
If it is really so, inetjoker was right, and thanks to vitamin C, even the pharmaceutical iodine tincture (if opportunely measured and diluted, not just a drop) could be used as a restrainer,
Originally posted 12 months ago.
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stragatto edited this topic 12 months ago.
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Wot is a DDR developer? A developer from DDR (former east germany)??
Posted 12 months ago.
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Interesting Stragatto, and according to wikipedia bot NaOH and CO3 (soda) will work the same to some degree.... admittedly I just had a glance on those pages, tonite was Finals of the local variant of xxxxx Got talent! :-)
Posted 12 months ago.
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Wow. I will have now to look into this.
Posted 12 months ago.
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DDR, yes : Deutsche Demokratische Republik.
It seems a part of the KBr was replaced with Benzothiazole in the Calbe R09 developer.
The combination Benzothiazole / KI comes from a DDR E6 developer.
But imho the KI is rather iffy, less universal than KBr -- quantities may be much more specific for a certain emulsion than Bromides (but as we make our own developers, no problem at all, ofcourse ;-)
Posted 12 months ago.
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I think the DDR people published a lot that was kept quiet on this side of the wall?
I have an old book from there, selbst-basteln......
Lots of info on how to make everything in the darkroom, rebuild cameras etc etc, don't remember if there was any recipes in it....
Posted 12 months ago.
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Quote=Wiki
"Kelp is a natural KI source. The iodide content can range from 89 µg/g to 8165 µg/g in Asian varieties, making prepared foods content difficult to estimate. Eating 3-5 grams of most dried, unrinsed seaweeds will provide the 100-150 micrograms iodide recommended daily allowance for nutritional purposes."
Freezedried kelp, freezedried coffee, soda and c-vitamin.. I wonder how much kelp you´d need for a working concuction? :)
Originally posted 12 months ago.
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FiatluX - Optimistic Illusions edited this topic 12 months ago.
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He he Fiat, you finally released us from the chemical companies!
Does this mean my local stash of KBr is worthless?
Hut here's a local headace: for about 4 - 5 decades they have tried to nudge us into eating kelp, not freeze dried, but kelp-based tablets!
Now theres another source for ingredients that keep the tablets together, but no sugar at least! They pushed this as health care back in the 60's.... dunno if its still for sale.-
Posted 12 months ago.
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Tried CCL with KBr substituted with 10g/liter Iodized (sp?) household salt ("Jozo") yesterday. No other changes. A lot better result with Tmax 400 - I had some Kentmere 400 and Fomapan 400 in the same tank and the negatives seem well on the good side of usable. Not as good as the Fomadon R09 1:100 (1hr stand) test on the same subject, but still OK. (Tmax came out less good here IMO, ISO 50-1600 tried, even 1600 was "overexposed" in look). Will put up the scans "real soon now" (almost all scanned).
Posted 12 months ago.
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I just read that the Jozo brand contains:
Iodine 5 mg/100 g.
and 2 anticaking agents:
E535 Sodium ferrocyanide
E551 Silicon dioxide
Posted 12 months ago.
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I will just grab my 1 lb box of KBr, weigh out 25 gram for a 250ml mix (10%) and use that - just finished my first 250 ml bottle, and I'va hardly made a den't in the 1 lb box.....
This means I have now around 80 films developed with KBr plus all those experiment without, started out before KBr with citric acid, did a lot of films with that, which also worked well, and now realize (after a swag of Tullamore Dew and some peace & quiet), that I need not concern myself with this salt business, I have KBr to my death....
Posted 12 months ago.
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Wow !! Salt works great. Thanks everyone who contributed on that find.
This is so awesome as my search is over. : )
Still true to the original idea of all the ingredients being found in a supermarket. A-Yay.
Cheers
Originally posted 12 months ago.
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jon caradies edited this topic 12 months ago.
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@ Hannu,
yep, I'm still not 100 % sure with Tmax400. Seems it must be rated very high and dev time maybe shortened.
@ Jon: I believe in the iodates and not the salt and would always declare that.
Thanks a lot everybody for the great insights.
Originally posted 12 months ago.
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imagesfrugales edited this topic 12 months ago.
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Here is a clear indicator of the influence of "Jozo" on Tmax development.
Kodak Tmax 400
Top snippets were cut off Fomapan, Kentmere and Tmax 400 film, these were only 'fix'-ed after exposure in room light - not in camera.
Upper, Caffenol-C-L with KBr replaced by 10g/liter "Jozo" household salt (NaCl + 5mg KI/100g), 70min stand-dev.
Lower: Caffenol-C-M, 13min @ 21°.
caffenol.blogspot.com - for recipes.
Browsing B l a c k M a g i c, this image LOBB
Originally posted 12 months ago.
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Hannu E. K. edited this topic 12 months ago.
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Naaaa you're comparing Cafenol CL developed film with Cafenol CM developed film, that is not the same IMHO.
I feel we need to see Cafenol CL with KBr compared to Cafenol CL with JOZO...
And Cafenol CM with KBr, to Cafenol CM with JOZO to assess this correctly. In the films I would like to see negatives exposed after 3 different ISO, to assesss wether one yealds better or worse ISO also.....
Posted 12 months ago.
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Well, I cannot help with KBr... but I have a set of 50 to 1600 ISO shots with CCL/NaCL+KI and a similar set with Fomadon R09 1:100, 1hr stand. Now I think there is some conclusions to draw from that already. I'll make them appear on my blog as time permits. Seem as life doesn't allow photographic technicalities to be completed right now.
Posted 12 months ago.
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I'm hoping Reinhold set up and show a test run that tyakes care of all the details - after all its kinda expected, his work is always immaculate!
Myself I could perhaps do it, but I'm buzy with unexpected trobles with tylenol, vitamin C and borax, and will present the facts there - no BS even if an experiment did not work out!
Same with me, life itself precludes too much, the garden has woke up from winter, there's a lawn, and yesterday we bought a log cabin - will require a lot of work, no net access and a vacation from this!
Posted 12 months ago.
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Now, I have created a blog post for this, here:
hearkane.wordpress.com/2011/05/29/caffenoljozo/
... but how it displays is a bit dissapointing - I have an idea on how to show larger versions of the images... but that will have to wait.
It simply is too late, and Sunday evening.
WRT: Comparing CCM and CCL, I'd be surprised if CCM would show less difference - but you never know. I've never tried CCL without bromide (which is the option I have) - I suspect a Tmax in there would come out very dark.
Originally posted 12 months ago.
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Hannu E. K. edited this topic 12 months ago.
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Excellent Hannu, I think this displays what you want very well.
However what I was after was not an example of that this works (even if that is very valuable) - I think the pictures Reinhold did show also displays that.
What I was after was more a comparison between similar films done with and without KI in the same mix, exposed similarly, and preferably also compared with a mix with KBr, exposed similarly.
I could do it, but haven't the time at the moment, as I'm preoccupied with other thiungs at the moment.
In short I'm after HOW WELL it works, compared to KBr.
Also to keep this in perspective, citric acid has been demonstrated to do the same, and can be found in a local foodshop as well, but I would not try citric acid in CCL due to low pH.
Posted 12 months ago.
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Sorry folks, my work is far away from beeing scientific. I trust on measuring by weight with a scale and dont like teaspoons, that's right, but all of my evaluation is done with "real" photography and no test charts or densitometers etc. Many others helped with providing data for different films and beautiful images, and that's what counts at the end imho. I can think a lot about comparing different methods, but to do that exactly is very complex and - yes - very boring for me. All I did was bundle the experiances of many others and my own. I draw my conclusions that did lead to the different recipes, 3 so far.Iodized salt works for me, it's up to you to decide what you do or don't. It's impossible to do everything myself and all reliable input is welcome.
My intension when publishing my findings about Caffenol only was to show that excellent, reproducible results can be obtained with a coffee based, homebrewed developer. If now we can say that iodized salt is able to substitute bromide, that's a big step forward imho regarding the homebrew thing and availability .
Collecting data which amounts of iodate are best for a specific film/developer combo will need some time and can't be done in a short time. It took more than one year to collect some data for the most frequently used films, but some are still missing. And I will not püblish a new recipe every week. I'm happy to work with my existing recipes and simply substitute the bromide.
Btw, recently I stand developed Acros100 (that works extremely well in many Caffenol-variants) in a low pH Caffenol without the Vit-C but with bromide (1g/l) of course and the result was very disappointing. Underdeveloped with massive "cloudy" fog and uneven development - unusable. Funny, Vit-C alone is a very poor developer, coffee alone is a poor developer, the combo is great.
Sorry for some offtopic gossip.
Most recent sample: www.flickr.com/photos/imagesfrugales/5773612259/
Happy developings - Reinhold
Originally posted 12 months ago.
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imagesfrugales edited this topic 12 months ago.
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Just a short note reinhold : what you point to about Vit C and Coffe is whats been debated, IMHO ascorbic acid on its own is not a poor developer, it's quite active. Coffe on the other hand is very weak, but it can be cohersed into doing something.
The combination is dynamite, compared to both ingredients.
There is some debate over that, combinations like that is very well known in developer recipes, Metol-Hydroquinone for instance is a classic.
Pairs like that are known as additive pairs, they enhance oneanother.
Some like to talk about super-additive pairs and offer difficult chemical explanaitons on that.
I'm a simple soul myself, and are satisfied to notice both enhance each other, and place final judgement in the pictures.
As for the subject here, I'd like at least ONE comparison, I don't think it suffices to show pictures and say the restrainer worked, since many types of film develops just fine in Cafenol C with no restrainer, and since an average scanner will hide the effects of a little fog anyways.
I do acknowledge the film strips shown here however, that show picture, and base fog in two strips side by side.
But claiming that this salt thing is revolutionary, is a bit exagerated, I can show the same results with citric acid, and never claimed that to no revolution, just a substitute for the industry standard that used to be KBr, and was more or less replaced with the advent of color chemistrry by BENZTRIAZOLE. (try finding THAT at the mall!)
Posted 12 months ago.
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I think (I tried K ascorbate) as a sole developer the VitC family is overdoing things - they will also reduce unexposed silver salts.
(no restrainer I tried was capable to stop this in a decent way -- in the end one ends with nothing on the film ofcourse).
But I do think when adding a relatively weak developer the main task of the ascorbates may be directed to reducing the oxidating fellow developer.
As for an optimal pH I recently always use a Borax buffer -- in this way it is even possible to use Rodinal 1+50 as a compagnon -- without the buffer the developer works too vigorous and fog will be the result.
I tried Rodinal between 1+250 and 1+50 and they all give good and clean results. (i even developed with a Coffee, Rodinal, VitC combo as developer with good results -- the Coffee slows down the development - between certain limits +- 1' per 4g/L)
(ofcourse this explains an additive developer, but not a super-add..)
Originally posted 12 months ago.
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RobbeK edited this topic 12 months ago.
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Reducing silver is the common explanation of a fine-grain developer ref. Hans Windish of W22 / W665 fame.
So that should be a welcome, especially since ascorbate-based developers are more active than most fine-grain developing agents from days gone by, i.e. they will give fine grain AND full ISO, while the stuff Windish was working with (he worked in war-time germany) was at times where developing agents was hard to find (rings a bell there) and he had to accept looing one or two full stops in his quest for fine grain.
Back in those days ascorbic acid was already synthesized, but at a price 100 to 1000 times higher than today, hence early researchers deemed it impractical for enthusiast use.... The first reports on AA as a developing agents are recorded in ca 1935....
Posted 12 months ago.
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I have sodium ascorbate here, btw, allegedly the stuff soda creates in solution when ascorbic acid is added to a soda solution.
Even if one compensates for the higher atomic weight od sodium ascorbate, compared to ascorbic acid (ca 30% increase AISTR) the activity is markedly lower than ascorbic acid, for some reason, so I have observed nothing of that reducing of silver salts, more like..... nothing.
Posted 12 months ago.
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I used FP4+, HP5+, RPX 100 and RPX 400, the films I have at hand at the moment. I know how they look developed in Caffenol-C without a restrainer. That's why I can claim that the iodized salt works with these films and it not simply works, it works great.. FP4+ and RPX 100 are almost as clear as a real transparency film. Believe it or not - it's up to you.
Cheers - Reinhold
Posted 12 months ago.
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Loooking forward to you putting it up on your blog Reinhold,its more "official" that way!
:-)
Posted 12 months ago.
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BTW, if you do a stand development with Caffenol-C-L you must use a properly working restrainer, otherwise the result would be desastrous. Iodates do the job.
I'm working on the blogpost right now.
Posted 12 months ago.
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never used cafenol C-L with success............
Thats why I championed an intermediate version, about at the time your first published CC-L.
I now see others have picked up on that idea.... Eirik amongst others...
Posted 12 months ago.
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"never used cafenol C-L with success............"
We know.
Blogpost done.
Posted 12 months ago.
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I only used it for Microfilm.
Posted 12 months ago.
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i have read that a super saturated salt solution might be suitable
as a fixer, if you add salt to your developer
can't you in effect convert your film developer into a monobath?
as it slowly develops your film, it fixes it as the developer exhausts ...
Posted 12 months ago.
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I have read that but never seen any results about sea water or salt solution. And then one guy used a salt solution for 3 days but again I have not seen the results. I think this fits in the Big Foot category.
Posted 12 months ago.
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You can , but not with ordinary salt, even "super saturated salt solution" which is just a fancy name.....
Salt works only as a wash bath, it faciliates washing out the DEVELOPER, not the insolible silver halides in the film.
That way the film APPEAR to be fixed, since there is no developer in the film emulsion (or very very little), no further DEVELOPING ACTION takes place - so seemingly you have fixed your film.
Sadly, even if you store the film in pitch darkness for the rest of your life, the film will turn all black from the undeveloped silver halides left in the film, which will be exposed to light the very second you look at it. Exposed, exited silver halides do turn black with time, even if stored in darkness.
The invention of fixer and the discovery of sodium thiosulphate as a fixing agent is one of photography's biggest inventions, bigger even than Daguerre's outdated process.
The process is actually quite involved and takes place in four discrete interconnected steps that are in balance with oneanother.
This needs to be studied thoroughly of course....
Originally posted 12 months ago.
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hfandrep edited this topic 12 months ago.
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I tried a saturated sodium cloride solution for hours and saw absolutely no fixing effect.. I knew before that it would be useless, but now I can say without lying that I tried it and it's nonsense. I get about 1 or 2 inquiries per month and am tired to answer.
Posted 12 months ago.
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I think the mistake comes from something that more or less (much more less than more) worked in the very early days (< 1840).
It certainly does NOT work with films : (and probably even very poorly on paper based (exclusively) on AgCl)
[http://www.flickr.com/photos/32981029@N07/5786615603]
Originally posted 12 months ago.
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RobbeK edited this topic 12 months ago.
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Update leafing through a standard tome on this, and happening upon "defects in negatives" : brown stain appearing after some time after washing : imnproper fixing or spent fixing bath, the stain is silver-halides remaining in the emulsion. Impossible to correct.
And yes I've seen this in a film or two fram early 1960's that I still keep - back in the day when I had no income, film was expensive, developer likewise and the fixer was used to the very last drop....
These negatives was impossible to print, since the photo paper saw this as darkroom light. Probably would have been printable as contact prints in bright sunlight....
Posted 12 months ago.
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btw:
A simple summary is that about six grams of salt makes a level teaspoonful
Posted 12 months ago.
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Can I just say that all this stuff is pure gobbledegook to me? Can someone simply say that you add ___ iodized salt (in USA it's almost any common table salt, like Morton brand) to ___oz. Caffenol-C solution?
In my case, it would be 8 oz. solution, and I would need fractions of teaspoons for the salt amount. Everything else is just way over my poor widdow pointy haid. My oldest brother inherited the chemistry gene, in fact he became a chemical engineer, and there was nothing left over for the final five of us.
Thanks, fellers.
Pete
Posted 12 months ago.
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The way I read it is you add a teaspoon to a liter there Brother... I must be wrong though as I always am in these situations. :-)
Posted 12 months ago.
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Ten four on that, a TEAspoon per quart is good enough, but have a look see that the salt is IODIZED, or else there will be no cigar
OOooPS edited gross typo, I did mean teaspoon NOT tablespoon, sorry if someone saturated their developer!!
Originally posted 12 months ago.
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hfandrep edited this topic 12 months ago.
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Hi f6.3, if you use Morten iodized salt you will need only about 1/4th of the salt that we have here in Germany and probably some other european countries. Because the Morton has more iodine, and iodide instead of iodate. So that would be about 1.5 g/l for medium fast or slow films (if you want it at all) and about 3 g/l for highspeed films.
No warrenty of course, the thing is quite new for me (us). And the conversion to teaspoons or whatever and other mix quantities must do somebody else. I'm used to the metric system and grams and liters, sorry.
Good luck - Reinhold
Originally posted 12 months ago.
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imagesfrugales edited this topic 12 months ago.
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This explains why we have no goiters here. :-)
Posted 12 months ago.
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just finished souping two rolls of Neopan Acros 120 in Caffenol-C-M plus salt (not really needed - i'll do an experiment to see any difference without salt).
Souped for 12 min at 20C with inversion first 30 sec then 3 slow inversions at the top of every minute.
Negs look good but thin - shot the film at 100 instead of 200 so i am a bit perplexed - either i need more time or try same time no salt next time.
I'll have them scanned up tonight
Posted 12 months ago.
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- also, i apologize for using imperial measures, as an engineer i much prefer the SI system - just need to get a scale to I can work in g/L instead of tsp/ounce
Originally posted 12 months ago.
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Colusite edited this topic 12 months ago.
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Perhaps, also my high iodate content morton's salt may be restraining the developer too much - now I have another variable.
:)
Originally posted 12 months ago.
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Colusite edited this topic 12 months ago.
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If you don't screw up you are not doing it right.
Posted 12 months ago.
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too true Larry, too true . . .
Posted 12 months ago.
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Here's a couple fo examples from my Acros experiments:
Both shot with a Moskva-2
Originally posted 12 months ago.
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Colusite edited this topic 12 months ago.
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Not bad at all!
Posted 12 months ago.
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For my next batch I´ll use salt instead, if it works as well on 4X5s I think its better to rename C-C-L to C-C-S or C-C-I or something similar to avoid misunderstandings . :)
Originally posted 12 months ago.
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FiatluX - Optimistic Illusions edited this topic 12 months ago.
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I like C-C-S
=)
Posted 12 months ago.
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Just a memo :
Potassium Iodide vs Potassium Iodate = 166 g/mol vs 214g/mol.
Roughly 4/5 ; incase your salt contains Iodides , it's 20% less to use.
Posted 12 months ago.
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- thanks!
Posted 12 months ago.
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CC-I is already spoken for
I termed that more than a year ago when Reinhold first publlished CC-L
It didn't work for me (and Reinhold is gritting his teeth over my writing this!! :-) ) so I developed an intermediate version that works well, now championed bu Eirik under a different nane .
Cafenol C-Intermediate with intermediate soda....
So CCS is the best suggestion here Fiat we remeber you for this:
Cafnol hall-of-fame Fiatlux gave name to CCS
And a nice weekend to all!
Posted 12 months ago.
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To be quite honest, my reduced sodium carbonate version of C-C-M and H has nothing to do with with your C-C-,I Erik. You never post examples of your work, so I've stopped bothering about your findings long ago. So stop getting your knickers in a twist. I got the idea from Mike, and have said so on many occassions, You are not the sole entrepeneur of Caffenol, Erik, there are others, I don't even count myself as one of them.
Posted 12 months ago.
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Trying the same combo as before but a quarter of teh salt and at two degrees higher (22C) - fingers crossed
Posted 12 months ago.
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6fpoint3 me too buddy. How much salt per 500ml or 1l of liquid. Thanks!!
Posted 12 months ago.
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Thinking aloud, taking notes:
The "Jozo salt" that I used for my single attempt has a content description saying.
- Fine household salt
- Anti-caking agents E551 (Silicon dioxide) and E535 (Potassium ferricyanide)
- Potassium iodide
Iodine content 5mg per 100g
... there is no statement on how much E551 (quite neutral chemically I believe) and E535 there has been added.
The wikipedia article on E535 states:
- "... together with iron ...is the main component of Prussian blue.
"In photography, it is used for bleaching, toning, and fixing."
So depending on the amount present, one could debate whether we have some restraining action from E535 too.
Originally posted 12 months ago.
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Hannu E. K. edited this topic 12 months ago.
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Hello Woo,
to determine how many salt you should use we must know which kind (brand) of salt you use and how many iodine (iodate or iodide) it contains. Reads on the package like xyz g/100g or %.
Originally posted 12 months ago.
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imagesfrugales edited this topic 12 months ago.
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Hi Hannu,
Some 10 years (and >) ago, I did a lot toning (still have the chemicals) IIRC for bleaching about 2% of cyanides were used (20g/L). Not possible such an amount could be in the salt. (Not that is very toxic.)
-- ofcourse do not mix with a strong acid -- you will get something as inside Zyklon B (HCN , hydrogen cyanide).
(strangely, here in Flanders I can just buy those 2 ingredients to make such things without the slightest problem )
regards Rob
Posted 12 months ago.
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imagesfrugales alas when I went to the supermarket the only iodised salt has no such information. I'll take a photo of the packet when I get home from work
Posted 12 months ago.
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E551 Silicon dioxide SiO2 is chemically quite inert. We have an electro-chemical plante here that produces Silicon-metal or Silisium-metal in german, the factory used to spew thick white clouds of SiO2, it is quite harmless, but the clouds blocked the sun, and SiO2 worked to make things grow green very quickly, but that is plant interaction and has nothing to do with what we are talking about.
These days Sio2 is used as an additive in the construction business, when they pour concrete, SiO2 is addet to give super-strenght in the iron-concrete structures, modern day skyscrapers would have been impossible without it.
SiO2 is quite harmless.
Originally posted 12 months ago.
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hfandrep edited this topic 12 months ago.
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E 535 Sodium ferrocyanide
There's a big diffenece in just one letter here! one has a (CN)6 group the other has a (CN)3 group the sodium salt, rather than the potassium salt is considered non-toxic, but all cyanides can release toxic gas like mentioned above in concentrated acids, we are then talking acid like in the stomac (1M HCL or slightly higher), so its safe to say there is very little of it in table salt....
Note that the potassium salt is mentioned as a photo chemical as outlined above, while the sodium salt, which is what is EU-regulated as E535 is not mentioned at all....
It is mentioned that cyanides can react and give a salt like KCl, and that is kinda similart to the KI we're talking of here, both as halide-salts (halides = Iodide, cloride, iodide....)
My gut feeling is that KI is the main ingredient, and that the JOZO brand has a little too low concentration, neing at roiughly 1/5 of the concentration Reinhold is working with.
Posted 12 months ago.
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Did some 4X5 testing, I used 10g/l maybe 8g/l would have been better. But all in all I have a good feeling about this salty business, I just need to finetune the salt/0,0025 % potassium iodate amount and make my Caffenol truly non-toxic! :)
Adox Pan 25, pretty straight scans,just some levels and sharpening done!
Originally posted 12 months ago.
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FiatluX - Optimistic Illusions edited this topic 12 months ago.
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And who says Sodium is bad for us?
Posted 12 months ago.
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It appears from this article (googlish translation from Swedish @ www.dn.se) that humans have a "taste sensor" solely for Sodium Glutamate - en.wikipedia.org/wiki/Monosodium_glutamate
Sodium appears here en.wikipedia.org/wiki/Nutrition#Macrominerals
Posted 12 months ago.
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What brand of salt are you using FiatluX?
Posted 12 months ago.
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Its from Lidl, dirt cheap and its called ChanteSel!
Posted 12 months ago.
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Our JOZO brand contains 1/5 og Reinholds, Eirik.
I'm a bit hesistant putting 50 grams in per liter, and besides I don't need to, I have KBr in abundance.
You still have any of the KBr I sent you around the time i thought you how to do this?
:-P
Posted 12 months ago.
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Oh, and it contains 0,0025 % potassium iodate (Kaliumjodat) = KIO3
just like Reinholds.
Posted 12 months ago.
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Just today I bought the iodated salt at the nearby supermarket: mine contains 0.005 % potassium iodate. I believe the iodate is reduced to iodide by the vitamin C.
Posted 12 months ago.
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The way we are going I want to know when we will be adding garlic. :-)
Posted 12 months ago.
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Lol, and maybe some yeast and oregano.. Then we´ll have Caffenol-P as in pizza
Posted 12 months ago.
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:-) Thing is we do try to take an obscure idea in a nitch and improve on it. I wonder what would have happened if we had the internet at the birth of photo developers and we could have started then.
No I think I have improved on Urinol as far as it goes when I added zink to my diet. ... Yes that was a joke.
Posted 12 months ago.
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Tonight I have run yet another Tmax 400/EI 400, in Caffenol-C-M + 10g/L NaCl/Jodie (15min@23°C) this time, the base 'fog' appears to be the same when comparing with the earlier basic CCM developed roll (13min@20°C, the second from above). I'd say any differences is so small that it cannot be measured by eye.
In the same tank, with the same chemicals was a Fomapan 400, which appears a lot better, fog-wise.
Anyone have ideas for more trials?
I have one cart left - what remains of my first bulk load roll. It is loaded with 30'ish frames - might be possible to use it in two or three parts (approx four frames is lost for every camera reload, the same way as with the Jozo test).
Originally posted 12 months ago.
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Hannu E. K. edited this topic 12 months ago.
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It may be that the Iodides and Chlorides are not so suitable for the Kodak T-grains.
- Certainly the Iodides will restrain AgI better than AgBr, but this may be very dependent on the emulsion (one should ask Kodak what's inside).
& then the Chlorides :
- they will not make the gelatine weaker in a way the developer will reach more depth.
- they like to oxidate the silver of the latent image. (you know about salt water and iron) ... however with the VitC around it's another question ; maybe probably it is prevented.
- they may react with other metals inside the emulsion -- my Double X seems to get a slight yellowish sheen (in Caffenol).
etc...
Originally posted 12 months ago.
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RobbeK edited this topic 12 months ago.
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FWIW, looking at the CCL/Jodide developed Tmax above makes me believe that there IS a recipe for Tmax type films. I'm not sure there is a CCM-type combination that works though. Maybe start from the reduced soda recipe and add salt?
The Tmax was fairly scannable, I'll have to ponder a bit on how to display it - need to find a way that shows the negatives "as is". I have good hope to make the result look good too, but that comes on top of it.
Originally posted 12 months ago.
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Hannu E. K. edited this topic 12 months ago.
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Hannu I think you are on to something here, reports of trouble with Tmax films have been frequent.
Posted 12 months ago.
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