RA-4 Blix: One Shot or Reuse?

[bvy]

For those of you processing RA-4, I'm curious, do you use the blix one shot or do you reuse it (with or without replenishment)? The Kodak docs and other resources suggest using all chemicals one shot. But then I've seen threads here suggesting that one benefit of using an intermediate stop/wash with RA-4 is that it makes the blix last longer -- which suggests reuse. For my 8x10 paper processing, I can use 60ml of solution one shot, or mix a half liter and use it for eight or nine prints. I'm using a drum on a motor base. I hadn't really considered an approach that involves replenishment, but I'm open to ideas. Curious to hear what others are doing...

 

[Mike Wilde]

Wel. with RA-4 in drums the challenge is actually wetting the print with the amount of fresh chems needed. I replenish RA-RT blix at 20mL per 8x10. So with drums it would be say 100mL to start, and re use that for four prints, then start to add 20mL per print after that just to be sure.

Pour off the surplus and accrue it for HHW disposal, before adding fresh stuff. I used to work with colour coded plastic mugs with open bottom handles that would hang over the edge of the wash basin that I used as my tempering bath. The mug had a line drawn in with a sharpie at the 100mL level.

 

[bvy]

Thanks. Do you use Kodak chemicals? 100ml for four prints before replenishment seems to be about two-and-a-half times their recommended capacity.

 

[markbarendt]

RA-4 is commercially used as a replenished system but with the small quantities I use running to exhaustion has proved more practical. (This is in contrast to C-41 where replenishing works great for me.)

To get the best capacity I have found that keeping the chemicals "clean" is the biggest issue. To that end I use the following process

Pre-rinse
Developer
Stop
Rinse
Blix
Rinse

I start by using the develop and blix times for appropriate for the temperature then after 4-6 sheets start bumping the time a bit. Mostly by mood.

I'm using a JOBO and normally about 160ml working solution, it is no longer a surprise when the 15th & 16th 8x10s come out just fine.

 

[Rudeofus]

First of all: over time you will read a lot of bad things on APUG about BLIX (compared to separate bleach and fixer), but these rants apply to C41 and E6, not RA4.

When I do RA4, I usually mix 500ml of working solution and use this for one or two days, which means one or two dozen test strips and about a dozen final prints 5x7" or 18x24cm. I never had any indication that BLIX was exhausted, but did use a fixing stop bath to reduce the load on BLIX.

 

[Photo Engineer]

I use:

Prewet
Dev
Stop
Blix
Rinse
Wash

I re-use the blix and replenish as Mike does. The developer is one shot!

PE

 

[polyglot]

Replenished, 10mL or 15mL per 8x10, Jobo processor. Kodak chems, Fuji & Arista paper. Acetic stop then rinse (total 30s) before blix.

i.e. all as per the Kodak instructions.

 

[bvy]

Thanks everyone. I'm processing in drums at 94F. I've added a 2% acetic acid stop bath and water rinse 30 each) between developer and blix. I use developer one shot.

Wel. with RA-4 in drums the challenge is actually wetting the print with the amount of fresh chems needed. I replenish RA-RT blix at 20mL per 8x10. So with drums it would be say 100mL to start, and re use that for four prints, then start to add 20mL per print after that just to be sure.

So can I multiply this by five -- that is, use 500ml of blix for about 20 8x10's, then start replenishing at 80ml for every four prints? The math and capacity works out the same.

 

[Mike Wilde]

I don't use drums now unless my roller processor is awaiting repair. In my roller processor the tanks are 2L. I try to remember to manually replanish after no more than 10 8x10's. I have never seen a variation in the prints doing this, but have not rigorously tested the appearance..

 

[DREW WILEY]

I don't bother. Everything one shot. RA4 chem is cheap. I use drums, so volumes per print are small,
even big prints. I only need 24oz of chem for a 30x40, and 1-1/2 oz for an 8x10 drum. I also have a replenishable roller-transport processor, but haven't even used it yet.

 

[Rudeofus]

I don't bother. Everything one shot. RA4 chem is cheap. I use drums, so volumes per print are small,
even big prints.

My biggest concern is not that a pair of 18x24 cm prints needs 180 ml soup, it's the countless test strips I need to get the final print. Even the smallest test clips need their 80ml to fill the 2500 Jobo tank to min level, and it's these test strips which would make single shot RA4 unnecessarily expensive for me.