Reversal RA-4 experiment thread.

[mshchem]

I don't think so. It's mostly an antihalation dye as I understand. I doubt removing it would magically bring color rendition and contrast in line with natural light (and consequently miles off a projected c41 neg).

I agree, even when we had Cibachrome and Ektachrome RC, it was much more difficult to come up with good prints than with color negative film and paper.

Still the antihalation layer should be filtering light, right? I didn't say I was going to do this. Still it's intriguing

 

[koraks]

Still the antihalation layer should be filtering light, right?

Maybe a little, but I'd wager that would offset fairly easily with a yellow filter of appropriate strength (for Fuji paper; cyan for Kodak). But most of the "problem" is inherent to the transfer characteristics of the emulsion itself.

 

[Raghu Kuvempunagar]

Rodrigo Silva sent me this video a while ago on Matt Marrash trying the process:


I contacted Matt and he said he hasn't figured out the color shifting.
IR and UV filters did not help (which was assumed to possible be the culprit to color shifting).

Does anyone think if this will ever be solved?
This process really inspires me deeply and I would love to see if there might be a solution.

Most of the original work was done by PE and Bujor. Not sure anybody reads the old posts on this topic.
https://www.photrio.com/forum/threads/now-this-is-cool.171296/#post-2230734

 

[mshchem]

Maybe a little, but I'd wager that would offset fairly easily with a yellow filter of appropriate strength (for Fuji paper; cyan for Kodak). But most of the "problem" is inherent to the transfer characteristics of the emulsion itself.

I agree, doesn't make sense if you are trying to make a well balanced color print. Way too many things going against a "normal", reproducible result. For creative type people might be fun. The development I see in the video, seems to me, to be less than optimum. From a reproducibility standpoint.

 

[koraks]

I think the RA4 direct positive option will always be a case of Lomo-ism. I'm sure it can yield nice images within this limitation though.

 

[Lightfire]

I've decided to continue my experiments with RA-4 reversal. And finally... I can actually say, I was able to get some photographs which look close enough to the original slides. Besides that... I've even found a way to print portrait photos without a too strong contrast. The whites are clear, the shadow details aren't really bad,

That's the original slide. As you can see, all of the shadows detail are still there. The prints shows some kind of posterisation in the sky area, but it's possibly because of uneven masking. The colors are VERY saturared. The color balance is a bit different, but it's actually fixable during printing.

I've also decided to try printing some photos, using my family's old ORWO slides. Those are pretty much low in contrast and it worked very well.

The colors are as close to the original slide as possible. The skintone is very nice.

This one is a bit less saturated than the original slide, but it's fixable anyway.

 

[grainyvision]

If I had the patience for working in complete darkness, I'd really like to mess around with RA-4 reversal again. I personally wonder if results of appropriate contrast and saturation could be achieved by using both a custom first developer and color developer. The first developer I've concluded will give the best results if using absolutely no bromide, and instead using only chloride and/or iodide as a restrainer (presence of bromide seems to be a major cause of the mottle effect), however figuring out how best to tweak each side of the developer equation is really difficult without sophisticated lab equipment and a whole lot of time and patience.

 

[Donald Qualls]

I bought an amber LED bulb (sold as a "turtle light" -- that is, a wildlife-friendly outdoor lamp) with similar spectrum to low pressure sodium. If dim enough, this should give a usable safe time for both Kodak and Fuji RA-4 papers, but I haven't had a chance to test it yet, and the 2W LED is quite bright, so may need attenuation.

 

[ragazzo]

Has anyone made an progress in this department? This is one of the most interesting threads I've come across. Curious if there've been any advancements.

 

[Donald Qualls]

Apparently Matt Marrash (Large Format Friday on YouTube) has been getting good enough results he demonstrated the process live -- with the color development done outdoors! -- at Photostock this past month. Filtration is the key, and that's going to require testing in the exact light for each session...

 

[Bronson Dugnutt]

Apparently Matt Marrash (Large Format Friday on YouTube) has been getting good enough results he demonstrated the process live -- with the color development done outdoors! -- at Photostock this past month. Filtration is the key, and that's going to require testing in the exact light for each session...

Aye, I saw that the other day as well. Achieving color fidelity during reversal cross-process requires heavy filtration when shooting in daylight. The basic starting point would be a cleared C-41 or ECN-2 film base with additional adjustments depending on the ambient conditions. RA-4 paper expects exposure to a tungsten light source(?) through the orange mask of the negative so there's usually a lot of blue light that needs to be culled from a daylight source. Folks with more experience color printing with non-tungsten light sources might be able to offer more insight into dialing in the correct filtration.

I sometimes apply similar filtering considerations when cross-processing ECP-2 print film (3383) shot in camera. Unlike RA-4 papers however, the print film stubbornly resists most attempts at E6 style reversal.

 

[Donald Qualls]

The basic starting point would be a cleared C-41 or ECN-2 film base with additional adjustments depending on the ambient conditions.

I've seen a couple different reports of getting close (enough so to use common warming filters rather than needing color printing filter packs) by using Ilford 0 and 00 multicontrast filters to start. These, together, are a pretty strong minus-blue. Of course, this also varies tremendously with the light -- "golden hour" is good, "open shade" much harder to work with. And 6 second exposures in daylight, according to Matt's latest video...

 

[Raghu Kuvempunagar]

@ragazzo: On Facebook I find people experimenting with RA4 reversal and posting their results. Here is one such post with notes from Experimenting With Photographic Paper As Film group.

 

[Taylor C]

Good day, Ashley!

Thank you for all of your efforts and willingness to share your findings with the rest of the world. I was wondering if you had any plans to revisit the first developer (RFD-1)? I'm looking to buy the chemicals to make the exact same formula to experiment with, and I'm wondering if anything has changed since then?

Thank you in advance for all of your time and efforts on this project.

Jack

I made my own first developer for RA-4 reversal, and the results are quite improved in terms of color balance and consistency, but I think I've pretty much hit my limits on reducing contrast with this paper.

Lets call the developer.. uhh, "RFD-1"

* 800ml of hot water
* sodium sulfite - 15g
* potassium carbonate - 15g
* HQ - 2g
* phenidone - 0.4g
* thiocyanate - 1g
* pot bromide - 1.7g
* iodide 1% - 1.4ml (1.5ml should be safe)
* fill with water to 1L

Usage: undiluted, room temperature (~22C), 3m development time with constant agitation. 2m will give slightly less contrast but also will have slightly warm grey whites and more green color crossing in shadows

The developer was designed to be a fairly alkaline developer for how much developing agent was actually in it (rather than resembling just a diluted developer). It was inspired by a combo of a homemade E-6 first developer recipe and a low contrast print developer. The amount of iodide and bromide was hand adjusted after mixing. I basically wanted something that would be low contrast, but also develop a good dmax (in negative). I also wanted something a bit more friendly than metol so I used phenidone. The amount of HQ is purposefully "inadequate" just so that it would behave mostly like a phenidone only developer, but with more stability and longevity, and also to further help dmax. The thiocyanate is another addition for improving dmax helping the whites "run away" a bit. The amount of bromide was initially 1g, but increased to 1.7g to slightly reduce tendency for highlights to clip at the 3m developing time.

The results were pretty surprising. It effectively makes the paper about 3/4 stops faster than D-72 with bromide/iodine and/or Dektol. It also requires a very different filter stack than I was using with Dektol/D-72, a lot less yellow and magenta filtration needed. With this, you will get some yellow looking stains around the edges of the print after the first developer. This appears to have no actual effect after color processing though.

The main benefits of this first developer is that it still pretty much minimizes as much contrast as possible from the high contrast RA-4 paper, but will also give very deep blacks, and brilliant whites. Color balance, and especially reproduction of the color green also seems to be a bit better compared to D-72/Dektol, though still not particularly great.

One other discovery. Color balance does not work the way one would expect. Removing yellow filtration will increase the amount of green. Decreasing magenta will increase the amount of blue. It can be really difficult to judge what the true results of a filtration change will be. Also, exposure latitude is still very narrow and even a minor filtration change like adding 5Y may require adjusting the exposure time.

Best print of the night processing:

* f/8, 8s
* 35M, 90Y
* 3m first developer, constant agitation
* 2m in color developer
* 2m in bleach-fix


Scanned print (edited the scan a bit to match the look of the print)
View attachment 231928

 

[Jimskelton]

Excellent thread. I'll have to try b&w developer with 1/10th the bromide to see whether I can eliminate the persistent cyan cast.

My 2 cents: Fuji Crystal archive paper has a blue dye on it which can be rinsed off. The resulting paper seems to be colour balanced for 3200K. Printing slides with rinsed paper only needs around Y25 filtration, and may not even need that when I try mixing b&w developer with 1/10 the bromide. And, shooting indoors under 3200K light requires only slight yellow filtration, allowing me to shoot at ISO 12.

Shooting outdoors or with flash still requires something like an 85b + a little yellow at ISO 6, which makes it almost usable to shoot in a camera--hand held in some circumstances.

I usually rinse the paper in 75F water in a tray, then transfer to a second rinse, squeegee, then put it on a drying rack inside a dark box I made out of foam board.

The advantage I found is an extra 2 stops when shooting in camera. This allows me to shoot with flash indoors more effectively. M3 clear bulbs work well, require only around Y40 filtration and I can shoot around ISO 10, with a guide number of 65, meaning on a Polaroid pack camera, can shoot at 5 feet at f/12.5. Unwashed paper had to be shot at an ISO of 3, with lots of filtration, and I was limited to a subject distance of under 3 feet, even with the M3 bulbs.

 

[DaveTheWalker]

Hello everyone,


I have been working on a method of taking and processing full colour direct-positive pinhole photographs in the Pinsta Camera (which allows development in the camera itself, without a darkroom), and wanted to share some results:

I used @Jimskelton 's method of washing out the RA4 paper before use, which pushes the speed up about 2 stops to ~ISO 12. To do this in the Pinsta is really easy because I can load the camera with stock paper, then rinse it out using the syringe holes. About 3 changes of water is all it takes for the dye to be washed out. I don't bother drying it before shooting and it doesn't seem to matter.

The filtration I used was from a Cibachrome filter pack. I just guessed at 50M+40M+50Y+40Y, and it wasn't a million miles off. This was low Winter sun in the UK. The filters took those two stops away again, sending me back to ISO 3.

With it being a pinhole, my exposure was a little over 2 minutes.

First BW development was in room-temperature Champion Suprol (1+9, 3 minutes, constant agitation), which is a Universal Developer and (probably) has lower bromide levels. Either way, it seems to work better than some others I have tried. It's also pretty cheap.

Stop bath is done through the syringe, then I remove the front of the camera to wash the paper and re-expose to (sun)light.

I used room-temperature RA4 colour developer for 2 minutes, then room-temperature Bix for another 2 minutes, followed by the final rinse.

It's slightly overexposed and perhaps a touch magenta-y, but pretty close TBH - especially for pinhole.

Really pleased with the results so far and looking forward to more good weather for some more photos. It's fun being able to make "instant" colour photos in a pinhole camera, in the field.

Cheers!

Dave

 

[koraks]

Jim, Dave, that's really interesting information you guys are coming up with! I never realized the possibility of washing out the filter dyes before exposing the paper. Makes perfect sense though!

 

[DaveTheWalker]

Jim, Dave, that's really interesting information you guys are coming up with! I never realized the possibility of washing out the filter dyes before exposing the paper. Makes perfect sense though!

It certainly helps. It doesn't get you all the way, but it's a double-whammy of increasing paper sensitivity and reducing filtration requirements, so it's worth considering.

 

[koraks]

Yeah, especially the filter reduction is an important part.

Perhaps I should give this another go one day!

 

[DaveTheWalker]

There's an interesting article in Silvergrain Classics on RA4 reversal for slide printing. Looks like Jeff Neale has got some great results by a combination that includes pre-flashing the paper with a filtered light as a way to balance the paper before the main exposure. I had similar thoughts myself, but hadn't had time to try them out yet. Glad to know I wasn't barking up the wrong tree!

The return of Cibachrome?

We talk to Jeff Neale has been making Cibachrome quality prints with the RA-4 reversal process

silvergrainclassics.com

 

[Lightfire]

So, it took 4 years to master the process. I tried a lot of papers and first developers, read a lot of old books and articles about processing slide films. And here I am, after all.

The first developer gives you an opportunity to make a whole bunch of prints without any noticable changes. It can also be replenished. I'm not going to post the formula, because it's now too good to talk about it. It gives zero fog, clean whites, zero color crossing and there isn't any kind of mottling (at least with the paper I use). I've tested it with only Fuji CA papers so far, but it works just great.
But ofc, it doesn't change the high contrast problem of the process. I mean, at all. You either use some old-contrast slides or use contrast reducing masks.

So, here we are, this picture is a scan of the original slide:

And these pictures are two prints from the slide, but with two different color corrections. You can also notice that the brightness and colors look a bit different from the original slide, it's caused by using an orthochromatic lith film for masking, using a panchromatic film will give me a result, which matches the original perfectly.

I hope I've inspired you to continue working with that process, because it isn't just some kind of lomography, it's actually a real way to print your color slides in a darkroom!