Reversal Paper for RA4 Processing?

Discussion in 'Film and Processing' started by alec, Nov 11, 2004.

  1. Is there any Color Reversal Paper out there that can be put through
    an RA4 Color Processor? If not, why hasn't this been developed? Is
    it that far technically out of reach?<p>

    I'm wanting to print slides w/o the interneg process and w/o having
    to scan the slide & print digitally.... I'm finally getting the hang
    of printing color photos and want to print some of my slides.<p>

    Thanks for your help!<br>
  2. You can make reasonable prints from some transparencies using Endura paper itself in a modified RA cross process.

    This is not for everyone, but is doable. The prints are rather high in contrast and have some mottle, but most low key scenes with lots of detail look quite good. I have a 16x20 drum processed print hanging on the wall next to me right now.

    Supra papers and Crystal papers will not work, as they don't clean out to d-min, and give rather ugly greens or reds instead of whites.

    Desiging a special paper would be the best route, but in todays conventional world, it is not economical. Besides, the process would have to be modified.

    If you don't like to scratch mix chemistry, here is the process (all at 68 deg F with CONSTANT AGITATION):

    Dektol 1:3 2'

    Stop 15"

    Wash 45"

    RA-RT dev 2'

    Stop 15"

    Blix 2'

    Wash 10'


    Lights can be turned on after the first stop bath. Your first exposure should be about 2 stops heavier than your regular negative print exposure, with about 20R more filtration.

    If you wish to scratch mix, and get sligtly better results, e-mail me.

    Ron Mowrey
  3. Just a small but addition to Ron's procedure; after the first 45" wash, reexpose the print to ambient light while washing for about 1 minute, otherwise you probably wouldn't get a reversal print. I have tried Rons procedure and get decent results using Agfa Neutol NE 1+7 for 2 minutes instead of dektol. If you contrast mask your slides, you will get rather satisfactory prints contrastwise. The only problem is slight mottle you may notice by close examination in even areas such as sky.
  4. Hi Rowland,
    just some clarification, 2' = 2 minutes and 45" = 45 secs?
    and RA-RT dev. how is this differant from regular RA dev.?
    I was also wondering about the scratch formula?

    Thanks in advance,
    Doug Westphal
  5. Doug;

    You are right.

    2' = 2 minutes and etc.

    RA-RT is the RA replenisher, which is slightly different than the plain developer. It is what I use, and is convenient for me. I use it for both negative prints and these positive prints.

    Scratch mix means I mix an MQ from individual chemicals to a custom formula of my own. I also modify the RA-RT developer by adding ingredients to it. These changes reduce mottle and contrast while improving process uniformity and dmin.

    I'm still working on this process.

    Ron Mowrey
  6. Me too, Ron, me too!

    For the moment, I have absolutely no problem lab-wise (I can say I do control the paper excessive contrast and I get no streaks whatsoever), using my chemical kits with your suggested procedure (if only people had the patience to read your postings to the end before "correcting" you...), not on slides, but as we discussed earlier on.

    My biggest problem is still the filter package, because, as you already know, I cannot use any Kodak, Agfa or Ilford 8x10 color papers in my particular set-up. I am stuck with Fuji Crystal, nevertheless decent, but extremely sensible to any color component change, or, as they say, to every 10 Kelvin degrees. Newly, I had reached both the orange limit and the cyan one with distinctive red, respectively green highlights. The best package is to be found in between 100Y 65M and 200Y 150M... which tells me exactly nothing, except that I still have a long way to go. See, when you deal with slides and your enlarger light source, it is relatively easy... orange mask, and you're done. As we both forsaw, when it comes to daylight source, it suddenly becomes extremely difficult...

    Sorry Alec for busting into your post like this, and I think many of you don't know what I am talking about. I should honestly open a separate thread... Alec's pertinent questions make me think it would be worth doing so.

    the rookie
  7. Bujor;

    Your MQ in this process has too much inhibitor action I believe. Therefore, too much AgX is left after the MQ step, and it is mainly in the top layer (cyan). Therefore, you get a high cyan dmin during the color development.

    That is why I have used a new MQ with little or no antifoggant. It gives better cleanout in all layers. I still cannot get it to work with Supra papers though, and others report that Fuji papers perform rather poorly.

    I think that this is an accident that EK did not plan on, and I just got lucky to get an image in this sort of cross process. I'm not going to object though. I'll take what I can get.

    Ron Mowrey
  8. My fault... As you recommended, I used no foggant too, but I didn't tell you everything: when I got my orange limit, I used an astronomic russian O-4 plus the darkroom optimal filter package. It was simply too much, that's why all turned orange. When I gave it up, obviously the filter package alone didn't do enough, and that's why I got cyan all over (because paper comes with the cyan protective layer). I have to tweek in more Yellow AND Magenta, and I'll be fine, I am sure. I'll try to post a combined jpeg (no Photoshop crap, cross my heart! The excessive contrast was present in my first attempts) the rookie
  9. I guess I've posted this before, but here goes again. Ron Mowrey
  10. Thanks for your contributions all. The short answer is "No, Alec, there's no color reversal paper you can stick in the Colex machine to get prints from slides." That said, it is encouraging that this could be done in a home darkroom, and I'm thrilled with (and understand) your answers. But I don't have a home lab. One day.<p>

    But to really understand the difference between this process and say, an R print can someone post a version of the home method vs a slide scan? Would be really interesting to see the difference between the two. It almost sounds like the results are similar to cross-processed films.<p>

    Thanks again!<br>
  11. Well dear Alec, for a moment I thought you really were one of the genuine people who wants to squeeze ice cream out of the coffee machine. I am truly dissappointed this is not true, and I wish you'll feel the need for a lab soon... Your BW work is exquisite, congrats! All that restricted dialog with Ron is about taking color pictures directly on paper, using fit cameras and original processing, entirely by-passing the film negative one-ton-nonsense (transferring, cross-processing, internegatives, third generations, pre-exposures, post exposures, negatives, dupes, slides, tungstens or daylights), but for sure nobody is interested in that... the rookie PS: Ron, speaking of Devil, this is my last result (with a BJ 4X5 straight on Fuji Crystal paper) by the way... Please note a significant progress in color balance (Graphex 175mm f/8, N=320 flashgun with additional warming filter of 15Y 5M)
  12. I need to ask an obvious question.
    Is this a quest to produce good prints from slides, or another excuse to fiddle with darkroom chemicals and essoteric processes that could be bettered by any $3.99 drop box at the grocery store or 18yr old running a Frontier?
    w/o having to scan the slide & print digitally
    I've tried to walk without using my legs, but it just doesn't work right.
  13. Gee guys;

    Here we are trying to take business away from the drop box and 18 year old running the Frontier, and right away the guy running the Frontier pipes up.

    I guess he needs our business, and thinks he can do better than we can. Lets all give up and give him our slides to print.

    It is interesting to note that people who cannot use their legs can get around just fine, and have developed some unique talents and strong arm muscles. Where would they be if they took Scott's advice and didn't try to get around without their legs.

    Just thinking about this kind of problem is an excellent exercise of the mind.

    Ron Mowrey
  14. Oh, Bujor B, if my wife could only here you say that. In fact, I am quite the experimentor, just haven't tried mixing chemicals at home quite yet. Perhaps after my next ICP course.<p>

    Yes, I missed the point that you were all talking about making prints directly onto paper. That's really incredible. From the perspective of a fine-art photographer, you're making art directly on the canvas. I personally think this offers quite a unique opportunity. It means that the final product, unlike a standard photo, is one-of-a-kind, and any duplication would result in something less than the original. I find that fantastic, and a major departure from "standard photography" where "limited edition" is only as honest as the printer.<p>

    I must try this.<p>

    But since I don't currently have a darkroom space, I did try your idea of squeezing ice cream out of our coffee maker. It didn't work terribly well, and I think the coffee maker may be broken. Please provide further instruction.<p>
  15. Alec, I said once I am sorry for comming into your post with a somewhat unrelated matter... (therefore even the adorable and charming Scott Eaton was confused for a while, but he was disciplined and put in line just at the right moment. By the way, Scott, you're quite boring with your omnipresent Frontier Candy Box, which they let you digitally drive since you were 18 years old and with your $3.99 Fuji Supremacy... Honestly, since when does one need permission to tell everybody in the forum how enjoyable it was playing with him(her)self in the darkroom, with or without using the legs?) Personally I don't see anything extraordinary in my technique... It is a thousand years old, pinhole photography was done like this for a time, then Polaroid reinvented it in a different fashion, and they already went out of business. Stop this endearing "fine-art" thing... I am a chemist, please... I mean... I have a real job! Further instruction would be to call Scott to fix your coffee maker. We all pay some Scott, or another "cloned mutant" there, to fix something, or to tell us what film should we use on a stormy night in Congo Brazzaville, between 3 and 3:15 am, in August, then we kick him out and call him back again to fiddle by his Frontier. Done! Seriously, if you are genuinely interested in experimenting with paper (or any other sensitive materials, in any normal electromagnetic radiation range), please let me know and I'll be more than glad to give you details. the rookie
  16. Yes Scott, this is a quest to produce good prints from slides. Yes we know all about the fantastic digtal methods, but still we find it desirable to go against the mainstream.

    I have tried the slideprinting with frontier. Have had one roll provia printed 10x15 cm, and the prints look good. The film was scrathced the entire length. I have also had some 15x21cm enlargements made from provia 35mm originals; they had visible pixels. Seems the scanning is not up to much more than 10x15 cm for good results. So; the frontier option is not very attractive if you want something big to frame.
  17. Bujor:

    I must say the images you've shown are absolutely fascinating. Granted, this is the internet, and all we're getting is some JPEGs that may or may not look that much like the actual print, but it's still looks excellent.

    I have used black and white paper in the camera, and chemically reversed that, but I never even thought to attempt this with color. However now I'm quite exited to try. Also, color paper is availible in pretty much any size, while the largest color sheet film (that I'm aware of) is 8x10". This has started the wheels turning in my head certainly: ULF color reversals..... Hmmmmmmm!!!
  18. And I thought nobody's interested... it is indeed fascinating! As I was telling one of discussion partners: before you go any further (and distroy some piece of ULF color paper), you have to experiment a lot to establish your filter packages, because you are dealing with the Sun, not the limited radiation emitting enlarger bulb. Until a true and affordable COLOR TEMPERATURE probe is invented, you need to play a lot withthe "base package" and then with Y and M, M and C, Y and C, or C alone, as well as (most importantly) in the lab, heavily depending upon the type of paper of your choice... and you'll certainly get good results, be it reproducing, be it suggesting the reality. Keep in touch! the rookie
  19. Bujor;

    I get seasick. Why did you have to post that image? Haaaaak!

    Anyhow, my post is to recommend a filter starting point. Color paper is basically tungsten balanced with an added bias of about 50 R. It also needs a good UV filter and a good IR filter if you can get them, otherwise you will have to use CC filters to compensate for the UV and IR.

    Color paper has an approximate EI of between 5 and 25 depending on illuminant and therefore filtration. I would start at 10, but perhaps your experience would be more useful.

    You might want to post some exact filter and exposure conditions.

    Oh, and don't forget false color (normal negative processing) and pinhole photography which is also made possible and economical by using color paper.


    Ron Mowrey
  20. Looking back at the "process"... you just put it in dektol, then through RA-4???? Really?? Wow, that's pretty straightforward.

    Mind explaining how it works though? With all the reversal processes I know, you develop the negative image first (as in dektol), then bleach it away, then continue exposing and re-developing the reversed, positive image. How does the bleaching get done in this case?

    Granted, the blix bleaches out all the silver anyways at the end, but... does the dektol somehow... de-activate the parts it develops, so the color developer can't work there? I must concede my knowledge of color processing is pretty basic.

    Thanks for this thread... too bad there isn't a "color printing" forum, cause I've always found that to be fascinating, but I guess it's becoming less and less popular these days...
  21. Dear Tadge, maybe the steps of the process are not very clear from how it was described in this post (you really have to read EVERYTHING): it is underdevelopment-overexposure and I think you just missed the point where the overexposure is made. Let me re-iterate for you: BW developer Dektol bath (although I don't use any of it... for the moment, I use a glycine based developer, but this will change pretty soon to a series of contrast-controlling A-B-C solutions set), then a short Stop bath, then TURN ON THE LIGHTS (very important!) then go on... alles klar jetzt? Does it make sense now? And I couldn't care less how "popular" chemical printing became lately and how many megapixels are to be made available in the near future. I am sure there will still be people like you, me and many others, genuinly interested in understanding and experimenting! After all, being a creative spirit means unicality, not popularity. the rookie
  22. Dear Tadge,

    I am going to adapt an E6 explanation to our particular ?paper? case (source: I would really like to quote the source, but the guys didn?t care to sign their names anywhere, so I hope my "plagiarism" will not bother them too much... after all it is common knowledge). All chemical reaction rendered as ?known? available upon request.

    Step 1: First development

    When you expose, a chemical change takes place in each of the three emulsion layers where light has reached. The change is in direct proportion to the intensity of the light; the brighter the light the greater the change. In this state the paper is said to have a latent image registered on it. The first developer converts this latent image into a visible black silver image in each of the three emulsion layers. The first developer is basically a conventional black and white developer and it is the most critical stage of processing. Any deviation from the correct time, temperature and agitation will lead to a change not only in the overall contrast, but also to a change in the color balance. The effects vary, but in general terms, reducing the first development time produces a yellow or red cast while increasing it gives a cyan cast. Similar effects are produced if the alkalinity of the developer is too low or too high. At the end of this step the paper resembles a black and white negative, but recorded in three separate layers. So you see, here is my playground...

    Step2: First wash

    When the first development is complete, you must remove excess developer left on by giving a short, vigorous wash, usually of fifteen to sixty seconds in length. The main purpose of this wash is to prevent carry-over of developer into the next solution--the stop bath--where it would tend to neutralize it. The thing to remember is that the developer absorbed by the emulsion carries on working during the wash, so the length of the wash is important.

    Step3: Stop

    To stop the action of the first developer and to prepare the paper for it's reversal exposure, you must treat it in a stop bath. This is basically a weak acid solution which neutralizes the developer retained in the three emulsion layers. It pays to keep a careful eye on the state of the stop bath, testing it regularly with litmus paper, or even replacing it regularly to ensure that it remains acidic. If the stop bath loses its acidity, usually by the first wash being inefficient and allowing excess developer into the stop bath, the developer will continue to work and give overdevelopment.

    Step4: Second wash

    This wash is most important, its job being to remove all traces of the first developer and stop bath from the film. Leftovers can affect the color development stage, producing color shifts and other "undesirable" effects.

    Step5: Reversal exposure (LIGHTS ON from now on until the end)

    At this point in the processing procedure, the paper has as appearance something like a black and white negative image. The parts of each layer which have not been blackened by the first developer comprise of unexposed silver salts and it is these which help form the final positive image of the color print. You must expose these silver salts to light. The problem is that, during the first development, the paper has lost a large proportion of its original sensitivity and this loss of speed is further hampered by the negative image which now exists. These two factors mean that the reversal exposure must be very intense. The most usual way to carry out the reversal exposure is by using daylight or relatively lot of time at the bulb light. Generally, it is all too easy to underexpose at this stage but virtually impossible to overexpose, so if in doubt, err on the side of overexposure.

    Step6: Color development

    The color developer contains a special developing agent which, after reaction with the silver halide to form metallic silver, reacts with the color couplers in the three dye layers of emulsion to form dyes. So, in each layer of emulsion, the areas which were not blackened during the first development now develop to form a combined silver and dye image, the color of the dye being of course yellow, magenta, and cyan. The amounts of dye and silver formed are in direct proportion to the amounts of silver halide left in the emulsion after the first development. In essence, color developers are similar irrespective of the particular process, the main difference between individual solutions being the particular color developing agent used. Other differences are usually in the additives which are used to modify contrast, assist the penetration of the developing agent, reduce graininess, and so on. Here is my other, smaller playground. Color development is not quite as critical of temperature as first development. Whereas the temperature of the first developer must be controlled to within half a degree C, the color developer often has a tolerance of two degrees either way (in fact I played with a lot more than that). But this is by no means universal. You must control the timing carefully, though, and standardize it to give you the results you want. In general, too long in the color developer will give you print that has a magenta bias and too short a time will give greenish results. At this stage of the process the paper becomes somehow milky; it contains, in each of its emulsion layers, a silver negative image, a silver positive image, and a positive dye image. It is usually just possible to discern an image, but it is very faint.

    Step7: Third wash

    As with the first wash, the purpose is to remove excess developer before it goes into the second stop bath. It is even more important at this stage to avoid the frilling effects of soft water because the high alkalinity of the color developer.

    Step8: Second stop

    After you have removed surplus color developer from the surface, that absorbed by the three emulsion layers must be neutralized and this job is carried out by the second stop bath.

    Step9: Blix

    This bath does two things simultaneously: Bleach and Fix. Before you can see your full colors, you must remove the silver produced by the first and color development stages. The bleach agent does not itself remove the silver from the emulsion layers; it merely converts it to a form which can be dissolved by the fixing agent. So all silver is removed and the positive image remains.

    Step10: Fourth wash

    bla bla bla

    Step 10: Free drying.

    Slightly different from the BW reversal process, which bleaches the first silver image, and keeps the second (reversed) silver image to the end. It is not complicated at all, right?

    the rookie
  23. Ok, just to be on the right track from the start.... We're talking about cutting standard print paper and fitting it into a large format camera, right? 4x5 or larger? So you put the paper into the cut film holder, and expose with [the discussed amount of filtering] for a [discussed amount of time].

    Then use Bujor B's process above for development.

    Guess I shouldda opted for the linhof technica instead of the Rollei 6008. More equipment to buy.

  24. Affirmative Alec,

    with only one remark: it is not "my" process... I'm not that smart! And you don't really have to cut color photographic paper, if you buy the right holders and the right paper (seriously, there are some issues here, trust me!)

    A Linhof is always good to have, I couldn't afford one...

    the rookie
  25. Bujor;

    IMHO, I think you have two redundant washes in there. I've found that they are not really necessary. (the one after the MQ and the one after the CD - the other two are essential - after the first stop and after the blix)

    OTOH, you got some excellent pictures. So, all things are a wash (pun alert). Congratulations on the teriffic results. And, don't be so modest. It is 'your' process. You made the pictures didn't you?

    You have shot the kinds of scenes that are perfect for the process, but I would think that portraits would be less acceptable. My nature shots turn out well, but my portraits show the contrast and toe problems too starkly.

    What is your opinion Bujor? And how about some actual exposure conditions. I'll want to stick some of that paper into my Horseman camera!

    Ron Mowrey
  26. Ok! This went way too far! Ron, are you serious? Are you really interested in my humble experiment? (of course you are... you are the actual maker of the process for reversing paper image... I know the USPTO #... I was only crazy enough to go further than copying slides in the darkroom, which was anyway so obvious I almost think you naturally pushed me outside in the daylight!)

    I have to clear up some things: the last attachment from Helsingor, Danmark is made exclusively using your process on a Provia slide... So is the one in Alaska, from another post, using a 400 APS Kodak crossprocessed as pseudo-slide. I wanted to touch Alec's subject as well.

    When I took the picture of my cat directly on paper, I guess I was extremely lucky. I manually fired the strongest flashgun I could get, and you can almost see his pupils coming from wide opened to closed (one second exposure). I even forgot to use the IR glass, but I think I've gotten the filtration almost right (just a bit of stray magenta there), exactly as I described in one of my other posts about "contact copies using a flash" or something similar (another source of mumbling in the forum)

    Piece of cake compared to the outside tweeking. The lizzard in AU was a special case. I think it stared like this for a whole hour, so in the end we had to kick it to be sure he was alive. This was actually the first decent direct paper photo I got. Quite frankly, I had to get rid of just a bit of orange in Photoshop to get the posted image. Well, there is a reason for that: I wanted to cheat and find out quicker how much more Y and M did I have to subtract to get the ideal filter package. Guess what... Photoshop sucks! If you are to apply their computations in broad air, you'll be better off color blind!

    At any rate, I am very near some decent and stable results and all who showed interest will get my "actual exposure conditions" via e-mail probably this weekend or soon after.

    Two more things Ron: as I mentioned in my message to Tadje, the explanatory process described is an E6-like one, which includes some extra washes, for him to understand it completely. In practice I APPLIED YOUR SUGGESTED STEPS EXACTLY.

    Portraits... ... I don't think it is an easy task at all. I think the color temperature of the face skin has a large variety, depending upon illumination, zonal reflectivity, emotional state, sex (or lack of it)... therefore they use generally a ton of mascara for both men and women when they shoot film. And there is another aspect: the paper low working speed makes it almost impossible to get a decent memento facial expression (where I came from, we say, they will all have that "full carrot deep in their arses" look upon their faces, half dead, half alive, like the sepia photos at the begining of the last century)

    the rookie
  27. nz


    Rowland could you give some info on the scratch mixing?
  28. Nick;

    Mix Dektol from scratch, but omit the bromide. Instead, use Sodium Chloride at about 100 - 500 mg/l in the working solution which is the concentrate you mix diluted 1:3 with water. You may also want to add extra Sodium Carbonate. I have doubled the amount of carbonate in this developer and get better whites.

    This developer will give about 1 - 2 stops more speed than regular Dektol with better whites and less crossover. It give higher contrast as well.

    Develop from 2 - 2.5 minutes in this MQ developer.

    Expect high contrast, and some degree of mottle in clear areas such as sky. The process will vary from batch to batch of paper and with the age of the developer. I suggest that you mix and store the developer for about 2 days before using it.

    This is why I don't suggest this cross process unless one is a very serious advanced color lab rat.
  29. nz


    I'd make up the D-72 at working strength fresh for each session. That would get around any developer aging issues I guess. Thanks.
  30. nz


    Or wait. Are you suggesting I should age the developer?
  31. Nick;

    Mix the developer from scratch and hold for 1 - 2 days, then dilute and use. The HQ is decomposing into HQ sulfonate which changes activity with time. I'm working on a better developer that is more stable.

    Ron Mowrey
  32. nz


    Thanks for the info. I'll hopefully have a chance to try it out soon.
  33. hi bujor b! I read this:
    "Seriously, if you are genuinely interested in experimenting with paper (or any other sensitive materials, in any normal electromagnetic radiation range), please let me know and I'll be more than glad to give you details."
    ... Do you use RA4 as negative film? I am using with pinhole cameras and get positive with strong bluish, I place one AV filter and improved enough now I'm tuning in chemistry. Any suggestions for shooting RA4 paper? Thanks for your help.

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