RA4 Reversal printing - results

[David Grenet]

Hi all,

I've been experimenting with RA4 reversal printing and I thought I'd share the results that I've had so far.

The process I've been using is as follows

• Expose
• Black and white develop in Dektol 1:3 - 3 minutes
• Stop - 30s
• Wash and expose - 2 min
• Normal RA4 process

The results have been mixed - my first attempt (first attachment) was on Kodak Edge paper from a Provia transparency (second attachment). Note the contrast increase and mottle in the sky and water. Exposure was 12s @ f11, 90/25/0 Y/M/C on a Durst CLS300 (note that Durst filter values are different from Kodak CC values).

Next I tried Kodak Endura Supra. Based on the experiences of others I expected this to work the best. Unfortunately it worked the worst of the three papers I have tried and simply wouldn't produce a good white (third attachment.) The transparency this was printed off is the fifth attachment. Exposure was 8s @f11, 85/5/0 Y/M/C.

Finally I tried Fuji Crystal Archive. There have been mixed reports on the results using this paper but for me it was hands down the best result (fourth attachment.) No visible mottle and not too much contrast. Exposure 10s @f16, 50/5/0.

I'd like to thank Photo Engineer for his previous posts on this subject and Stephen Frizza for letting me use his darkroom.

I hope this has been interesting and informative for you all!

David.

 

[Photo Engineer]

David;

I have posted many items about this including the process and examples. Many have done this. Endura works most repeatably for me, but the CA varies a lot from reports I have had.

You have given no temperatures for the process. I use 68 F and the RA-RT developer replenisher. It is so touchy that many things like that will give different results from different papers.

PE

 

[David Grenet]

That is exactly why I was so surprised. I have all your posts on this subject that I could find (both here and on photo.net) bookmarked. The initial dev/stop/wash was done at room temp in trays; it then went through a roller transport machine (at 95F?)

I should note that the Endura I have is a little old (not as old as the Edge) although it still gives good whites in normal neg-pos printing. The CA was fairly fresh.

 

[Photo Engineer]

It looks that #3 is about 1 stop under exposed.

I have a 16x20 hanging on the livingroom wall using just about that process. I use Dektol as well.

I have dozens of sample pictures from people sent to me from all over the world using this method, and although it works, you need to select the transparency carefully due to contrast. In addtion, all reports say that CAII and Supra III and II will not work as well as Endura, but then all paper formulas change. I used Portra.

PE

 

[David Grenet]

Thanks for the reply.

In addition to the images posted, I tried to print some contact sheets. I settled in the exposure I did because at one stop over I was losing detail. However, now that you mention it, the one stop over proof sheet has a lighter background tone (around the film) suggesting I need to try more exposure (and perhaps find a transparency that will cope with it better!)

I will keep trying with the Endura and report back (probably won't be able to do any more for about a week).

David.

 

[Matt5791]

Those look superb, especially the last two! I had never considered this was possible, never even thought about it!

Matt

 

[Derek Lofgreen]

Okay, I have looked but I can't find the other posts you said are out there. Can you or anyone point me in the direction of some detailed instructions on how this is done. Thanks. They look promising.

D.

 

[Photo Engineer]

Bujor B. posted a whole raft of pictures taken in 8x10 or with a pinhole camera. There are a half dozen more on Photo net and several here.

PE

 

[pentaxuser]

Like the others I am fascinated by this. I have several dozen transparencies but gave up shooting more because of the expense of the Ilfochrome process for making prints using this processand that I suspect will turn out no better than RA4 neg prints. However I would like to have a go with these transparencies now I know that it is possible, otherwise theey are destined to remain simply transparencies to be viewed occasionally on a very small viewer.

PE. I have never seen any articles on the process. Would you be prepared to give us the benefit of your skills and knowledge here with an article or maybe a thread or as Derek has mentioned a pointer towards an article. I have looked at a number of colour processing books, have seen nothing about it and like Matt never even realised that it was possible.

Thanks

pentaxuser

 

[David Grenet]

Well, for those looking for more information there is a discussion (there was a url link here which no longer exists) which includes a pdf summary of the process towards the end.

There is also this post on photo.net which includes some of the samples by Bujor about his 'in camera' technique.

Enjoy

 

[Derek Lofgreen]

David,
You rock! Thanks for the links.

D.

 

[pentaxuser]

Thanks David That's a big help.

pentaxuser

 

[hka]

Does it only work with Dektol?? or is any other standard b&w developer usable?

 

[Photo Engineer]

D76 will not work in my experience. Probably no solvent developer will. The paper emulsions are too soluable and you lose a huge chunk of speed.

PE

 

[srs5694]

Like the others I am fascinated by this. I have several dozen transparencies but gave up shooting more because of the expense of the Ilfochrome process for making prints using this processand

I wouldn't count on RA-4 reversal as a substitute for Ilfochrome (or discontinued reversal papers/processes). Results tend to be high in contrast and the color balance tends to be a little weird. Some paper/developer combinations produce mottling. If you've got the right subject, the results can be good (either because the problems are minimized or because the odd characteristics work with the subject), but as a general-purpose way to get prints from slides, I don't think RA-4 reversal is a good way to go.

OTOH, perhaps there's some "magic combination" of paper and developers that will make it work well. If so, I've neither found it nor heard about it.

By all means, experiment. I've got a print hung on my wall that was made with this process. I've got more prints from slides hung on my walls made by scanning and digital printing, though.

 

[amellice]

What is the purpose of re-exposing? I'm not clear on this step. Is it just open the room light for 15 seconds on the front of the paper (emulsion side) and the back of the paper? What is then the back has to do with it? Can someone shed some light on the re-exposure step

 

[Sirius Glass]

As an experiment it is interesting to me and shows that it can be done. Would I ever do it? No. End of interest or in the Web World [/interest]

 

[Photo Engineer]

What is the purpose of re-exposing? I'm not clear on this step. Is it just open the room light for 15 seconds on the front of the paper (emulsion side) and the back of the paper? What is then the back has to do with it? Can someone shed some light on the re-exposure step

As in any reversal chromogenic process (E6 comes to mind), a light re-exposure or chemical fogging step is needed to make the positive silver halide image developable.

PE

 

[amellice]

As in any reversal chromogenic process (E6 comes to mind), a light re-exposure or chemical fogging step is needed to make the positive silver halide image developable.

PE

but what about exposing the back of the print? what difference does it make to expose the emulsion side for 30 seconds or exposing the emulsion for 15 and the back for 15?

 

[pentaxuser]

This has raised my interest again and also raised a number of questions which may be obvious to others but not to me.

1. We know that Dektol works but would Ilford Multigrade B&W developer also work?

2. The times given by PE for the RA4 processing are, I assume, for room temp processing. Would 35C in a Jobo with times altered for 35C work also?

3. We know the time used by PE when projecting the transparency onto the RA4 paper but is there any way to estimate what the right time is or is it simply a question of lots of test strips, using a F4 aperture?

4. We also know the M and Y balance used but is this close to what all transparencies will need and if so what was the enlarger system used i.e. Durst, Kodak filter values? If the balance varies a lot between each transparency, how does one begin to work out what the balance might be?

5. Once the RA4 paper has been developed in Dektol or other suitable B&W developer, what appears on the paper- a negative in B&W? If at this stage the RA4 has been used for test strip columns can you work out which is the right exposure?

6. I assume that the RA4 paper needs to be exposed under the enlarger in either total darkness or colour safelight. If so, at what point can the lights go on and stay on?

Some of these questions may seem naive but any help will be appreciated on this.

Maybe the answers can be added to the very good pdf that a APUGer has compiled on PE's process

Thanks

pentaxuser

 

[Photo Engineer]

but what about exposing the back of the print? what difference does it make to expose the emulsion side for 30 seconds or exposing the emulsion for 15 and the back for 15?

The negative image can shield any image behind it, so you have to expose front and back. This is also true with E6 light reversal.

PE

 

[Photo Engineer]

This has raised my interest again and also raised a number of questions which may be obvious to others but not to me.

1. We know that Dektol works but would Ilford Multigrade B&W developer also work?

2. The times given by PE for the RA4 processing are, I assume, for room temp processing. Would 35C in a Jobo with times altered for 35C work also?

3. We know the time used by PE when projecting the transparency onto the RA4 paper but is there any way to estimate what the right time is or is it simply a question of lots of test strips, using a F4 aperture?

4. We also know the M and Y balance used but is this close to what all transparencies will need and if so what was the enlarger system used i.e. Durst, Kodak filter values? If the balance varies a lot between each transparency, how does one begin to work out what the balance might be?

5. Once the RA4 paper has been developed in Dektol or other suitable B&W developer, what appears on the paper- a negative in B&W? If at this stage the RA4 has been used for test strip columns can you work out which is the right exposure?

6. I assume that the RA4 paper needs to be exposed under the enlarger in either total darkness or colour safelight. If so, at what point can the lights go on and stay on?

Some of these questions may seem naive but any help will be appreciated on this.

Maybe the answers can be added to the very good pdf that a APUGer has compiled on PE's process

Thanks

pentaxuser

The only developer I tried that would not work was D76.

I have never tried other than RT (20C) processing.

I got all process and exposure times by trial and error.

I got the filter pack by trial and error.

After the first developer, you would see a weak negative silver image.

You can turn on the lights during the wash which is after the stop.

PE

 

[amellice]

The negative image can shield any image behind it, so you have to expose front and back. This is also true with E6 light reversal.

PE

I'm sorry Ron I don't get what you are saying, what is the image behind the negative image? isn't the negative image is the image?

 

[Photo Engineer]

There are 3 imaging layers in color paper. If you have a blue, then the cyan (top layer) and magenta (middle layer) are exposed to form 2 dyes which appear blue. But, the details in the blue, such as any design or pattern, are black and need yellow dye, but it is being shielded by any silver in the top 2 layers. Therefore you have to expose through the back to expose the yellow (bottom layer) through the paper base.

PE

 

[pentaxuser]

Thanks PE. It certainly sounds like the proverbial "cut and try". If I have read you correctly the weak silver image in the form of test strips from the B&W developer may not be enough to ascertain which exposure was correct so until you have the RA4 strips after the whole process it might not be possible to know which strip is the correct initial exposure under the enlarger.

It strikes me that you might need to try various strips at a selection of times and Y&M balances and on each new time correct for the change of Y&M .

On that basis it might be that you could be close to the best exposure and colour balance after one 8x10 divided into say 5 strips of 2 inches each but the final print might well need at least 2 x 8x10. Hopefully from a similar set of transparencies you could then get very close to the right exposure and colour balance once you had the first "perfect print"

Does this make sense?

Thanks

pentaxuser