RA-4 one shot (dilutions)

[brbo]

I process prints in Jobo and I'm using Kodak Ektacolor RT/LU one shot (35º, 45s).

Last nite, at the end of the session I was left with less than 60ml of developer and blix that I use for one 10x12" print (I tested that I can get away with as little as 50ml once I made sure my drum was levelled). So I used 30ml of developer and 30ml of water and processed the print at my standard temperature 35º, but increased the time to 1min. I extended blix time to 1:30min.

Can you tell which is which?

(prints look much nicer than this quick phone "scan")

Quite happy to know that you can get away with 1+1 dilution without compromising print quality.

Any other "cost optimising" suggestions? I can only process prints in drum, no space for anything else. I'm already using Kodak Endura Premier paper in 12" roll that I cut to 10x12" sheets.

 

[David Lyga]

You have dared to confirm what I have already been saying, ad infinitum. Good for you for this important discovery. (Maybe you can dilute even more.) - David Lyga

 

[Photo Engineer]

Did you make a guess David?



I think it is the one on the bottom. The blacks look less dense to me.

PE

 

[koraks]

Any other "cost optimising" suggestions?

Replenished RA4.

I'd guess the top one is the 1+1 dilution, but it sure is a very very close call and any difference is extremely difficult to spot.

 

[mshchem]

With Cibachrome, I always used a mix of 50:50, used and new, for all the solutions. A sort of replenishment. I would save some of the used solutions from a earlier run to start a new session.

Bertram Miller wrote about RA4 use back in the 80's, he used a Kodak rapid color processor, was using something like 60 mL per 11 x 14, IIRC. Chemistry is so cheap I don't get too concerned.

 

[David Lyga]

Did you make a guess David?



I think it is the one on the bottom. The blacks look less dense to me.

PE

Honestly, PE, any minute difference could comfortably as ascribed to a slight difference in development time. Of course, if it had been simply reused, the second round would make the developer a tiny bit weaker and if the times and temps were truly identical, maybe that second round would be ever so slightly less dense. But, I will say this with assuredness: if the second round was 'accommodated' with a bit longer development time, the results, at least theoretically, would be identical for human eyes. Even with 'fresh' developer being used with a 1 + 1 dilution (as done here), extended time would equate the two (for human eyes). Increased dilutions (as done here) would do the same if development times were to be slightly enhanced.

Thus, the 'decision' as to 'which is which' becomes pedestrian, moot, because any qualitative deviation can readily be corrected. - David Lyga

 

[brbo]

I think it is the one on the bottom. The blacks look less dense to me.

Correct, the bottom one is 1+1 dilution. Except that in real life you can't actually tell the the "pure" blacks apart (the sprocket holes). And if you observe left side of the pictures (left side was further away from the window when I took the picture of the prints - so more evenly lit) you can see that the dark parts are actually denser in the 1+1 dilution print. Which, as mentioned, is probably more down to any variation in exposure time (I don't think my timer is that precise - this was aprox. 2s exposure) and/or development time.

Replenished RA4.

How would replenished workflow with drums go? Would I still be able to do a prewash (I once got a bit of streaking with Kodak paper without prewash, never with Fuji, but remember, I'm very new to this so when I say "once" and "never" it doesn't mean much)? As far as I understand you replenish 10ml per 10x12" print. I can see that I could easily "lose" 10ml per print because I try to drain the developer as quickly as possible and stop the development (though not using the proper stop, just water at the moment). Plus 10ml to replenish and then I'm only saving 10ml over 1+1 one shot regime. OK, it's additional 30% more savings. But I'd probably have to learn how to check if the replenished solution is still within parameters and correct for that. What would that require?

 

[koraks]

I found drums a hassle, but it would be just like another approach; maintain a working stock volume (say, a liter) which you take the required amount from for a print and put it back with the rest after developing a sheet. Repeat, and once every few prints replenish the worming stock volume according to the data sheet of the developer, while monitoring pH as well as it may start to drift at some point.

 

[pentaxuser]

I found drums a hassle, but it would be just like another approach; maintain a working stock volume (say, a liter) which you take the required amount from for a print and put it back with the rest after developing a sheet. Repeat, and once every few prints replenish the worming stock volume according to the data sheet of the developer, while monitoring pH as well as it may start to drift at some point.

I haven't done RA4 prints in a long time but what you describe is what I recall I used to do. The stock developer sits in a 600ml Jobo container in the Jobo water bath to maintain the temp and after each print you pour the 140ml of developer back into the 600ml container then after so many prints you dump some of the 600ml and replenish from the main stock container. As I recall it this means replenishing the 600 ml container which sits in the water bath at 35C with stock that may not be at 35C but in my case when that point was reached I was usually at the end of my RA4 session. On the next printing occasion I simply heated the fully replenished 600ml container to the temp required in the Jobo water bath and began again

pentaxuser