I am not aware that RA-4 processes are washless. I'll have to check.
I do know that C-41 can be washless but only using the C-41 Flexicolor RA Bleach and Fix. They have been modified to prevent problems with any possible retained silver complexes. In addition, the Final Rinse RA III must be used with this washless process.
If you don't use the proper chemistry, you can end up with unstable negatives.
You can use the RA chemistry with a wash however, with no problems.
PE
Yes, you can make a film blix!
Now, let me explain the consequences and the reasons behind the problems.
1. Ammonium Ferric EDTA only comes as a liquid of about 40% concentration or about 400 g/l.
2. Ammonium Thiosulfate only comes as a liquid of about 60% concentration or about 600 g/l.
3. Sodium salts of the above are less soluble and come as powders. They are far less active than the ammonium salts.
Now, let us look at the E6 bleach and fix concentrates. The bleach itself consists of 2 bottles that total to approximately 3 Liters all on their own. The fixer consists of one bottle of 423 ml. Each of these makes up 1 gallon or 3.8 L of solution.
If you mixed each one up and then mixed them together to make a blix, the resultant mixture would be 50% more dilute than the original leading to less activity.
If you mix them together in 1 gallon (3.8 L) then they have the same working strength as desired in separate bleach and fix, but the oxidation and reduction power of the two main ingredients conflict and the solution becomes short lived (less than a month, perhaps less than a week).
Either of these would make a suitable blix given enough treatment time, but the first, if it worked, would be slow, and both methods would yield a very unstable blix. The second would be fast but very expensive.
Lets now look at C-41. Bleach III is at working strength as-is, so that adding hypo solution only dilutes it further and weakens it. The same arguments hold as above regarding stability. The blix would decompose rather quickly. So, you cannot make a good blix from C-41 chemistry as it exists. You need to reformulate and cant use Bleach III.
Powder kits made with sodium salts of the ingredients is possible, but these become very slow acting. Remember that sodium based fix solutions are not rapid fix solutions. You have to go to ammonium based fix solutions to have a rapid fix!
So, here is a quick rundown of the above:
Use solid powders and the blix is too slow.
Mix the bleach and fix parts normally then mix together, and the kit becomes weaker and less stable due to dilution. It also requires more time due to the loss in strength and you end up right back where you were with a bleach and fix situation. Mix the two parts without dilution if possible and the blix is fine for rate but much less stable. It becomes a one-shot essentially.
In the end, you have about equal costs or more with a blix due to the shorter shelf life after mixing and the lower capacity.
With a bleach-fix, the process is a tad more complex but not necessarily longer.
With a blix, there is a chance to have silver retention with some film / blix combinations. This is due to the heavy silver load, the type of silver developed, and certain inhibitors used in color films to control image quality. The dyes also act to protect the silver from the bleach and so the dye cloud must be rendered penetrable by the blix.
There are ways to limit any problems with blix kits.
Use a long blix time! Use 2x 4x the suggested time or more. It will not hurt. It does make the process longer.
Mix the two parts right before use and in the quantity you are going to use. Dont re-use it. But, this increases cost.
There is a summary of some of my work over a 30+ year period on bleaches and fixes. The Bleaches and Blixes included Copper, Cobalt, Iron and various organic oxidants in order to optimize Blixes for films.
As Ray said above, the problems with Blixes used with films were known years ago.
Best wishes to you all, and whatever you choose, may it work well for you.
PE
I can tell you how to make your own RA-4 Blix and your own C-41 bleach and fix. That is about it.
PE
Can you help us out here. I would like to make my own if it is a reasonably safe process and can be done with our normal weigh scales.
As long as this subject has resurfaced I am still looking for a good c-41 kit that uses bleach and fix separately. I was able to pick one up from Catlabs a while back but this one is no longer available.
A Kodak Flexcolor kit seems available, but it appears only to be designed for the mini-lab systems and there is no direction on how to use it with a Jobo, if it can at all.
If anyone has any guidance on this I would appreciate it, otherwise I am back to the Tetanal or Rollei kits.
The bleach and fix set here can be used with a Jobo.
PE
A note of clarification though. In your article you indicate that both Rollei and Digibase kits are already separate bleach and fixer kits but from what I can tell online the current Rollei offering is a Blix kit.
I've looked at this kit in the past before reordering from Freestyle.. and/but perhaps I'm dense, can't seem to understand by searching in the archives if you can just successful just mix 1 litter at a time with this kit, and store the rest for future use?You are right, I just stumbled upon this one Rollei Kit.
Yes... thank you.. in your previous posts.. you convinced me... that's why I'm still trying.. to go Blix free.Both Kodak and Fuji "agree" that a blix is bad for film and have made them separate as bleaches and fixes. Other companies, in attempts to upstage this process with a quicker process with fewer solutions have come out with blixes for films. These are either 2 part or 1 part.
ANY blix is less useful, less stable and has less capacity than any bleach then fix process.
If you insist on using a blix, you are going "against" years of process development at the major companies and you are wasting time and money on these second and third tier blixes. AFAIK, the developers are just fine, but you do need a final rinse with all kits.
PE
@peter k.: yes, you can mix less than the whole 5l at once. You will have to make sure, though, that the remaining concentrate lasts until it is used up. Use protective gas for all concentrate containers except BX-A and STAB. The opened and then properly protected and resealed concentrates will stay intact for about a year, after which BX-B and CD-C concentrates will go bad. In my experience BX-B goes bad (yellow milky precipitate) long before CD-C keels over (strong discoloration). You don't need BX-B if you follow my BLIX--->bleach&fix conversion instructions, but replacing CD-C requires some experimentation.
The reason I write about "protective gases" is that I don't want to be seen as a sales clerk for Tetenal (as I sure aren't one). Nevertheless, the only commercial and dedicated product for this purpose which comes to mind is Tetenal's Protectan spray, which you can order from Freestyle and probably a range of other sources (PS: I don't work for Freestyle either). Some people have reported success with lighter fluid, and if you feel adventurous you can try gas cylinders with anything inert that's heavier than air. The Protectan spray comes as simple spray can with a short piece of tubing which allows you to reliably fill bottles with narrow mouthes. It is overpriced IMHO, but will last much, much longer than the 5l kit you protect with it.I need a little more specific's on protective gasses, as I use marbles in pet bottles for B&W with D76, or Hc110 who's longevity last forever, anyway, often without anything done!
There are two effects at play which go in the opposite direction:Ah... never got clarity out of this one.. does putting the chemicals in the refrigerator help..
Some do it, others say it makes no difference.. its the oxygen.. thru the wrong bottle container, not topped off or not sealed properly. Which to me, is the culprit, ... What say you?
Sorry about the lack of clarity.What do you want? This is a broad question.
RA4 blix:
100 ml NH4 Fe EDTA solution (standard in the industry)
100 ml NH4 Thiosulfate solution (another industry standard
10 g Na2 EDTA
10 g NH4 Sulfite
All in 1 L of water with pH to 6.5 with either acetic acid or ammonium hydroxide.
This should do.
PE
As I understand it, this is a kit from Freestyle that is not a blix kit.So in the U.S. where do we find separate bleach and fix kits or reasonable volumes of these chemicals for home users? All the kits Freestyle sells are blix kits.
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