Reversal RA-4 experiment thread.

I'm back again with more novice questions
As always, I'm appreciative of any responses~!!!!

I am intrigued about the prospect of prewashing my ra4 paper but I have some questions.
I have read this: https://emulsive.org/articles/my-ra...hooting-and-processing-colour-paper-negatives

1) can the runoff from the washed paper go down the drain? or would that also have to be disposed of properly (i.e. in a facility)?

2) The site above mentions ISO of washed paper being 12. Can anyone confirm this? It would be wonderful to have a second source backing this.

3) It mentions that without the coating the temperature of the paper is 3200K. If my lighting conditions were also 3200K, would this mean that wouldn't need any filters?

4) is the paper more toxic without the coating? Should one handle the paper any differently following prewashing?
Thank you in advance for your guidance and mentorship, photorio respondents. It means the world!

sc0rnd said:

I'm back again with more novice questions
As always, I'm appreciative of any responses~!!!!

I am intrigued about the prospect of prewashing my ra4 paper but I have some questions.
I have read this: https://emulsive.org/articles/my-ra...hooting-and-processing-colour-paper-negatives

1) can the runoff from the washed paper go down the drain? or would that also have to be disposed of properly (i.e. in a facility)?

2) The site above mentions ISO of washed paper being 12. Can anyone confirm this? It would be wonderful to have a second source backing this.

3) It mentions that without the coating the temperature of the paper is 3200K. If my lighting conditions were also 3200K, would this mean that wouldn't need any filters?

4) is the paper more toxic without the coating? Should one handle the paper any differently following prewashing?
Thank you in advance for your guidance and mentorship, photorio respondents. It means the world!

Click to expand...

The Naked Photographer made a video about RA4 reversal and he found no differences at all in speed or color balance with or withour prewashing (by the end of the video).

sc0rnd said:

1) can the runoff from the washed paper go down the drain?

Click to expand...

Officially probably not. But for the few boxes/rolls of paper you'll likely process in this adventure, I wouldn't make things overly complicated.

sc0rnd said:

2) The site above mentions ISO of washed paper being 12. Can anyone confirm this?

Click to expand...

It's probably fairly close, give or take one-two stops depending on lighting conditions etc.

sc0rnd said:

3) It mentions that without the coating the temperature of the paper is 3200K.

Click to expand...

I don't think so. The 'coating' which isn't a coating at all but a dye embedded in the gelatin layers is intended to cut down reflections/halation inside the paper itself and thus improve sharpness. It apparently has a very slight effect on color behavior, but this is really a sideshow and not very significant. I base this on discussions with the people who manufacture the paper. They also indicated that the color of the dye as such isn't very critical and there are other options that would have different colors and still produce the same mentioned benefit. Keep in mind also that Kodak's papers used to be pink, while the configuration of layers was otherwise conceptually similar to Fuji's. If the purpose of this dye was to somehow match the paper to a particular light source (which is NOT the case, color-wise), it would have been kind of odd that one manufacturer would end up with a magenta dye and the other with a cyan dye.

sc0rnd said:

4) is the paper more toxic without the coating?

Click to expand...

No. Also, the paper as such does not pose a risk to a user in any way, shape or form, with the possible exception if you're going to burn the paper in an unventilated space. There are also no particular concerns in handling RA4 chemistry in a home darkroom provided basic safety measures are taken (don't spill too much on your hands, don't get it in your eyes etc.)

Successful reversal processing depends mostly on controlling contrast of the scene and filtering either the light source(s) and/or using lens filters to balance the color.
Keep in mind that the paper is not and never was intended to be used with continuous light sources, so color response will never be quite as nice as color film.

@koraks @halfaman

Thank you endlessly for your responses! god, I love this place!

The naked photog's video is interesting. I watched it before I ever attempted ra4 reversal, but it's more useful now I've had some experience (and approximately one successful attempt ).

@koraks
it sounds like your experience was that pre washing/rinsing did increase the paper's iso but did not have a very significant effect on color/filtration? Even a higher iso would be worth it for me as I'm shooting pinhole and when my experiments have failed lately it's been after a many hour exposure.
I guess I just have to experiment a bit more to see if prewashing does *anything* since there is no consensus.
thanks so much for the detailed response, I am really super thankful for it.