Experimental color reversal (partially successful) without E6 chemistry

I have done E6 processing at home in the past with good success but the kit did not lasting long and I shoot slide film quite seldom so it is not worth investing in E6 chemistry. Send away to AG Photolabs have been the standard mode of operation for the last few years. That though became more inconvinient when I went back to processing C41 and ECN-2 at home.

A few years back I remember reading about people trying out home color reversal using film B&W developer and C41/E6 color developer with from what I could tell various success. I have also kept an eye on the Negapos method from Japan with negative film used for color reversal in a method B&W paper developer and C41 color developer. Now I wanted to see if it was possible to replicate the E6 process at home with a paper B&W developer and RA4 color developer.

The basic recepie should be

- Take paper B&W developer add some KCSN

Processing as follows

- Pre heat with 38degC water

- Process in the above hacked B&W paper developer

- Wash

- Take film out 

- Re-expose

- Back into processor

- Develop in RA4 

- Wash

- Bleach

- Wash

- Fix

- Wash

- Stabilize

How difficult could it be?

It turns out quite tricky to the dillution and processing time of the hacked B&W developer correct.

In the past I read somewhere that it was important for the first developer to be aggressive. I tried to study recepies of color reversal first developers and compare it with the B&W paper developer I choose to try with - Ilford PQ universal. I selected this one as it also can double as B&W film developer. After looking at the FD receipes online comparing with the Ilford PQ I decided to go for 1+4 dillution and add approx 0.5g of KCSN and give it a go of 6min. I selected the 6min as I wanted a process that was timing wise similar to the "proper" E6 process.

Film used to experiement: Agfa Precisa CT100 (bought fresh in 2014 stored in freezer ever since)

First try was a disaster - film strip of four shots came out with a slighly yellow orange base and resemblence of a negative. Rexposed under halogene light which I had calculated to be equivalent to  800 footcandle-seconds. Scratching my head not knowing what went wrong I did the process with only one frame, this time using a strobe (as I read someone had success with it). No real change.
I though realized after this that the hacked B&W developer seemed way to strong for the film as even the sprocket borders where blank.
Next increased dillution to 1+9 and 6min. After this one could see sprocket border started to become darker but not black and there was some color residue as well.
Next stayed with 1+9 but went for 3min, result a little dark and a little cold greenish blue colors.

On the rigth track but I wanted 6min.

Next increased dillution to 1+19 and 6min, still dark and colder.

Left 1+19 6min, Right 1+9 3min
Neutral point selected in silverfast during scan at window frame on right slide part

Next 1+15 and 6min , half washed away, black sprocket frames more like gray.

Next about 10 shots in 1+15 at 4min. Way too dark and still cold. My cheap PF3650u cannot get anything useful from them but using either the slide copier on the camera or the Microtec M1 could actually get some results from it. Just for the reader to understand how dark the slide was, with ISO100 on the DSLR camera and lens set to f5.6 on a overcast summerday, camera pointed to the sky during day time the exposure time was 2s. The first two are scanned with Microtek M1 and post processed in lightroom. The darkness really pushed the equipment to the limit and technical artifacts are clearly visible such as banding on the original scan. The last is with slide copier on a Sony Alpha A55, the color temp slider (warm/cold) maxed out at 50000 in lightroom.

  

I have read somewhere that the pH value of the color developer will create the color cast. Too acid = magenta cast, too alkalic green cast. Maybe the RA4 developer is too alkalic.