Every professional lab owns a proper print processing machine. Do you think I will be able to match the quality and details of a print processing machine, even if I get every step perfect and accurate in Tray RA-4 printing on my own?
Yes. I only use trays, but when I started out printing RA4, I had a friend run me through the process, using some of my own negatives, and using his machine & chemistry. The results were identical to what I got using trays, at room temperature, with no temperature control whatsoever....it just takes a little longer and you have to do everything in complete darkness of course.Do you think I will be able to match the quality and details of a print processing machine, even if I get every step perfect and accurate in Tray RA-4 printing on my own?
Every professional lab owns a proper print processing machine. Do you think I will be able to match the quality and details of a print processing machine, even if I get every step perfect and accurate in Tray RA-4 printing on my own?
It's an added expense of course but my experience as far as having some light in the room is concerned is that a DUKA sodium safelight on a low setting and preferably pointed at the ceiling so the light is reflected will give you enough light to see where the trays are and allow you to turn from the enlarger and step over to the trays but yes with practice this can be done in the total darkness.
As long as the developer in the tray is at 20C or a bit above then about 2 minutes will develop a RA4 print so ambient i.e. a comfortable-to-be-in temperature is fine As far as getting it as good in terms of colour balance and exposure as that which can be achieved by pressing buttons in a mini-lab then this takes a bit of practice in a darkroom but there is no reason why if the negatives have been properly processed your home RA4 should not be as good as that of a mini-lab
pentaxuser
Drew, just not true based on my and Bikerider's experience. There is a level of sodium light at which it is perfectly easy to see in terms of getting around and handling trays of what you regard a potentially dangerous chemicals so has to be a good thing to have surely?But any constant light would have to be so far away and so dim as to be almost useless.
I have done RA4 in trays/dishes, Jobo rotary processing in drums and I own a Durst Printo roller transport machine originally purchased 30 odd years ago specifically for RA4 processing
What you wish to do is perfectly possible, but quite fiddly. For print to print and negative to negative quality, tray processing is hard, but eminently doable. That said, the fumes you will inhale, unless as Drew suggests, you have air being drawn over the trays and outside of the darkroom will eventually become a health issue.
I too have the Minilux and exactly as Drew suggests, is how I've used it. In another life I did RA4 printing in an industrial darkroom lab, if you test correctly, there is pretty much no scope for any kind of safelight. However you won't notice the slight differences in your situation. That doesn't mean that these days there may be a safe safelight, but I wouldn't wish to put money on it if I was a betting person.
I would suggest the best quality in the safest manner for home use, is using drums for RA4 printing.
For what it's worth, with drums, you can run with a developer, bleach and fixer baths and keep on using the quite expensive bleach for almost double the other baths. If you run a stop bath immediately after the developer bath, then your bleach really will last until it is exhausted from bleaching, as opposed to running out of bleaching capability due to developer contamination. Bleach is by far the most expensive component in the process, anything that prolongs it will save you a fair bit.
Mick.
The Thomas sodium vapor safelight with the color filters (or equivalent ) work well. It takes my night vision about 10 minutes to kick in, but I can see well enough to shuffle around a bit. If you can as Donald suggests find the right safelight, and give your eyes time to adjust tray development is a reasonable solution. I have found with RA4 that, more than other processes, you develop to completion. I use the old Kodak processors that require total darkness, I run at 38°C, I've developed anywhere from 1 to 2 minutes with no appreciable differences. Clearly the paper and chemistry is designed to run warm and fast. I would try to find a way to maintain your tray temperature at or above 85F.With a little testing, and strict time limits for handling time, you can even avoid the "complete darkness" requirement -- an LED safelight at about 575-590 nm wavelength, with a narrow spectral peak, if dim enough, can have a safe time for RA-4 paper of ten minutes or more. That's plenty of time to pull a sheet out of the package (or cut one from a roll), place it in the easel, expose, and process into blix (after which light exposure no longer matters). You need to test your safe times -- same test as you'd give for a new/old safelight -- and the light levels are generally lower than they'd be with an amber safelight for B&W, but it's done in some color darkrooms.
All good advice. I've always used stop bath, helps reduce weird stains too. And agree safelights are a bit like a light leak. It's only safe as long as you don't expose the paper to it long enough to cause a problem. There's no safelight that allows more than brief exposure at a distance.I have done RA4 in trays/dishes, Jobo rotary processing in drums and I own a Durst Printo roller transport machine originally purchased 30 odd years ago specifically for RA4 processing
What you wish to do is perfectly possible, but quite fiddly. For print to print and negative to negative quality, tray processing is hard, but eminently doable. That said, the fumes you will inhale, unless as Drew suggests, you have air being drawn over the trays and outside of the darkroom will eventually become a health issue.
I too have the Minilux and exactly as Drew suggests, is how I've used it. In another life I did RA4 printing in an industrial darkroom lab, if you test correctly, there is pretty much no scope for any kind of safelight. However you won't notice the slight differences in your situation. That doesn't mean that these days there may be a safe safelight, but I wouldn't wish to put money on it if I was a betting person.
I would suggest the best quality in the safest manner for home use, is using drums for RA4 printing.
For what it's worth, with drums, you can run with a developer, bleach and fixer baths and keep on using the quite expensive bleach for almost double the other baths. If you run a stop bath immediately after the developer bath, then your bleach really will last until it is exhausted from bleaching, as opposed to running out of bleaching capability due to developer contamination. Bleach is by far the most expensive component in the process, anything that prolongs it will save you a fair bit.
Mick.
All good advice. I've always used stop bath, helps reduce weird stains too. And agree safelights are a bit like a light leak. It's only safe as long as you don't expose the paper to it long enough to cause a problem. There's no safelight that allows more than brief exposure at a distance.
I'm sure this is true. And like war ships, the interior lighting is amber/red to preserve the night vision of the crew. Where product is not handled, in halls going from place to place the low light is maintained. It's amazing how well you can see after a half hour in real darkness.This is true even for black and white papers -- or panchromatic film. if it's bright enough at the paper surface, and exposure long enough, even a very pure red light at 650 nm will still fog either multgrade or graded B&W enlarging paper, but I recall reading from multiple sources that safelights were used inside the Kodak film factory, while running -- workers who had to move around the place had flashlights with deep yellow-green filters (precisely at the eye's sensitivity peak, so as to be as dim as possible). They were just about bright enough to not run into stuff -- which, mostly, was what was needed.
A two minute development time works perfectly even at 68F (20C) with Kodak RA-RT Developer/Replenisher. I do tray development at this temperature.I run at 38°C, I've developed anywhere from 1 to 2 minutes with no appreciable differences. Clearly the paper and chemistry is designed to run warm and fast. I would try to find a way to maintain your tray temperature at or above 85F.
Have you tried 3 minutes? I ask because at higher temperature it seems like, once it's done, it's done. Leaving it to develop longer has no effect. I know with the old Polaroid professional, peel apart films, extending development at room temperature didn't seem to matter.A two minute development time works perfectly even at 68F (20C) with Kodak RA-RT Developer/Replenisher. I do tray development at this temperature.
Not much in my experience. My development time at room temperature is 90 seconds. Extend it to 120 - no difference. It's develop to completion.I guess I'm asking is timing critical at 68F?
Timing does matter. From my experiments RA-4 doesn't develop to completion. Or it might be more correct that it can be always bleached too much and that's where variance comes from.
Even with B&W it can be developed to completion or not.
When I tried it, it was a lot of hassle. Worth doing anyway when I had to do few small prints before digital time.
Consistency in timing and temperature was the key.
I'm glad this is coming up now because I've been wondering myself if it develops to completion. When I googled I found a lot of people saying it develops to completion. This is news to me but I always develop 2 min at 70 d.
However I'm positive someone knowledgeable, and I'm pretty sure it was Photo Engineer, said that RA bleaches to completion.
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