Dark Streaks on RA4

[John Olsen]

Kodak recommends the use of ordinary stop bath to reduce the staining. As A.G. mentions here, developer and blix can cause a stain. I've used stop with RA4 forever. You can use water as well. Tube processing is vulnerable to this problem.

I think the stop bath is essential. In my experience water doesn't cut off the development sharply enough and lets the print keep developing until its kind of brownish.

[shallabal316]

Thanks for the additional feedback here, it’s really helpful. The Arista instructions are completely lacking mention of wash between dev and blix. I’ll definitely try a stop bath. Do I just use an acetic acid bath, or is there a better/different recommendation for RA4?

[shallabal316]

I process 16x20 and 20x24 RA4 prints in a CPP3 with 3063 drum. I have seen similar streaking on some prints (usually places with highlights like skies) which is caused by the developer coming into contact with the Blix and causing a stain. I would add a 30 second wash step in-between your developer and Blix stage and that should fix it.

With regard to other notes you posted, I'm not familiar with your drum numbers. But your chemistry sounds too low. If you see the Print Drums section below in Jobo's documentation, you'll note that 8x10 drums require at least 100ml of chemistry and 16x20s 200ml. I usually double these amounts for my own work to get adequate coverage. Remember, you can replenish your developer after every run to maintain its strength. See Fuji's documentation for replenishment rates if being color correct between print runs is important. Otherwise, you will have slight magenta wandering (less) between run to run.

http://www.jobo-usa.com/images/manua...capacities.pdf

With regard to comments needing to dry the drum in-between runs, this is not necessary in my experience. Simply empty the drum of any remaining water after your run, load your new print, then before you begin your next run on your Jobo, do a water pre-rinse. So, it will resemble:

30s Pre-rinse > 1m developer > 30s rinse > 1m Blix > x 3-6 rinses to clean the print/drum

Thanks for this recommended process. I am going to try this and include a stop bath.

I think these drums are both from an older series. I’ve been using 250ml or so in the 8x10 drum and 300ml in the 16x20. I did notice that if the 16x20 drum is not perfectly level, one cannot seem to add enough chemistry to get the far edge of the print. This 16x20 drum states 180ml min, so I’m hoping the 300ml is cutting it. If the stop bath doesn’t solve, I’ll move to 400ml on the big drum.

Side question, am I wasting money on the Arista kit? I feel like I’ve been extra conservative due to the kit prices. I’ve seen some higher volume developers and blix that are sold separately and appear to be more cost efficient, but I’m unsure of what the right combo or process is to use those chemicals. Apologies if this has been asked a thousand times.

[sharktooth]

Does your old Jobo drum have the ribs to ensure the entire paper surface is held tight to the drum wall? It sounds like you're using more than enough solution if the paper is held flat to the drum. On the other hand, if the drum is missing the ribs, or if the ribs or paper are not installed properly, the paper won't be held tight to the drum wall. If the paper is just loose in the drum you'll need waaaaay more solution to insure proper coverage, and defeats the whole point of using a rotary drum.

[shallabal316]

I use the Kodak RA4-RT kits. I find them economical enough. I also use an acetic acid stop followed by a water rinse before the blix. The larger the print, the more I find it necessary.

Thanks Greg! You posting just reminded me that you have a great RA4 video I need to go back and watch again. Your channel has demystified much of the darkroom process for me, so thanks for all of your content.

What’s the rinse for between the stop and blix? Does carryover affect the blix somehow?

[shallabal316]

Does your old Jobo drum have the ribs to ensure the entire paper surface is held tight to the drum wall? It sounds like you're using more than enough solution if the paper is held flat to the drum. On the other hand, if the drum is missing the ribs, or if the ribs or paper are not installed properly, the paper won't be held tight to the drum wall. If the paper is just loose in the drum you'll need waaaaay more solution to insure proper coverage, and defeats the whole point of using a rotary drum.

My drums are indeed ribbed and stick pretty well to the sides. Hard as heck to find much info on them though! I believe they’re from the 80s due to the FRG origin printed on the larger one. They’ve held up well!

[agregov]

If you don't have large volume of chemistry to go through, it probably makes sense to stick with the Arista unless you haven't been happy with the results. I use a table top processor (Fujimoto CP-31) for most of my color printing so I buy a larger amount of chemistry. I buy Fuji chemistry:

Developer Replenisher
https://www.pakor.com/fuji-digital-r...-repl-4-x-10-l

Bleach Fix
https://www.pakor.com/fuji-cp-ra-p2-...-repl-4-x-10-l

[Duolab123]

One point. You could replenish and reuse. Doesn't have to be an elaborate scheme. Use a 1 liter bottle of developer, take whatever you want for development. Before you pour it back into the bottle, add 60mL of fresh, per 8x10. Then top off with the used developer, throw away any excess.

I like the Kodak or Fuji chemistry. If you are in the US Unique photo in New Jersey is great, you can get less than case quantities.

[Duolab123]

Oh and Pakor is a great company, great service.
LEVEL YOUR PROCESSOR BY SHIMMING THE ENTIRE UNIT UNTIL THE DRUM IS LEVEL.

[shallabal316]

Thanks for the recommendations on chemicals.

@duolab123 I did level out the unit when I set it up initially. My problem is forgetting to adjust the support rollers to the correct orientation when switching between drums of different diameters. I blow one sheet about every time I switch from film to print processing. Luckily I haven’t made the same mistake on film.

I finally got to do some printing today, and used the stop+ rinse. 3 prints in and no streaks!