RA-4 AT color HELP please!
Rhett James Barnes
parts: Color Developer and Bleach/Fix, which says you can use an
optional stop bath or a water rinse).
I'm doing my stuff in a hand-rotated drum in a tap-water warm bath.
Using the directions from Beseler exactly (ok, I added a 30 sec pre-soak)
for 19 and 17 degrees on two different days, I was getting ok prints, but
they really were a little dull. They didn't have much color saturation (I
chose a really colorful test neg, where I had a "real" print to compare).
There were no obvious flaws, the blacks were black, and the whites were
white. And considering that the neg was Ektar, the color corrections
weren't that bad (90Y 50M). I first tried on Kodak Supra III, then jumped
to Fuji C.A. type C in hopes of getting better color. But it didn't
help. Not completely horrible where I could know something absolutely had
to be wrong, just not nice enough to inspire me to ever want to print
anything.
So tonight I decided to experiment to see if I could do better, though I
was worried that the 17 degree water temp was a little cold (they only
rate to 16 deg). After the failure with the Fuji, I started to play with
the Color Developer time, which I originally had raised 50% above
Beseler's recommended minimum value, hoping maybe to get more color? As a
begin to reduce the Color Dev time, I seemed to be getting better and
better color saturation. I added a stop bath to help reduce the time.
Finally I got a really awesome test print and decided to do an 8x10 on the
Fuji paper, which turned out absolutely beautiful. Every color was MUCH
more vibrant, yet there was hardly any color shift when compared to the
"bad" prints. This print was probably better than the machine print with
which I was comparing it. But I had done this print a little after the
expected life of the 2oz of chemicals I was using (should be good for
about 2 full 8x10's, I'd done about 3 to get the nice test print, probably
4 including the "good" print), because I wanted to get a nice print
without chaning any variables.
For the next print I did pour out a fresh aliquot of chemicals (including
stop bath), and did an identical test print just to make sure. It was
back to the same crappy thing, no color saturation at all.
I've since tried to reduce the Color Dev time with fresh developer, and to
dillute the stuff, but haven't really had any luck. I've been reluctant
to "exhaust" the chemicals again like I did the first time, because I'm
just wasting paper if this is not really the problem; it'll mean throwing
away 3 sheets of paper just to test it. I don't think that I'm agitating
any different, but I may try a test with really fast/slow agitation, just
in case.
So basically, I have one really beautiful print from my RA-4 AT kit,
really done at a A.T. bath temp of 17 deg, and have not yet figured out
how to reproduce it.
Anyone out there who can help me out of this mess? I'd LOVE to make
prints like the "good" one I got, but I'm not really sure I'd want to
waste my time if they're all going to come out like the "dull" ones.
Thanks for any tips.
-Rhett
Rhett James Barnes
that is very informative. Bill said that he can't post it directly, so
here it is in all its glory]
Date: Tue, 7 Dec 1999 12:15:24 -0500 (EST)
From: "William Laut" <wl...@alpha.delta.edu>
To: Rhett James Barnes <rbar...@san.rr.com>
Subject: Re: RA-4 Help
MIME-Version: 1.0
Hello Rhett,
First of all, thanks for emailing your question to me. The College
upgraded its news server some weeks ago, and the Post function broke in
the process. Beause I dial in using a dumb terminal and modem, fixing the
Post function is not high on their priority at this time. Consequently,
until they either fix the Post function (or I get around to writing a
point-to-point DLL driver for my VAXStation, whichever comes first), I'm
stuck in read-only limbo.
Also, if you don't mind, I would appreciate you posting my reply to the ng
on my behalf, in case there's anyone else who's experiencing the same
problem as you are.
On Tue, 7 Dec 1999, Rhett James Barnes wrote:
> William-
> After seeing your excellent posts about RA-4 chemistry on
> alt.photo.darkroom, I was hoping I could get you to help me with my novice
> RA-4 AT problems. For someone who supposedly has a Ph.D. in chemistry, I
> really know precious little about what's actually going on in color
> development (I kind of like it to be more of an art than science).
>
*VBG* I miserably failed high-school chemistry many moons ago. I suppose
I'm making up for it now since I got involved in photochemistry. :-)
>
> But it
> looks like you've spent the time to get a very good handle on the
> chemistry.
>
I know enough to prepare it from scratch and how to calibrate it using
control strips, but not enough yet to understand the intricate chemical
reactions involved, and how I could "dope" the developer to produce other,
interesting effects. That I'm still working on.
>
> I'm including my news-group post to describe my problem. It's
> pretty much accurate, except that I've now tried a couple more variations,
> and it appears that the only time I'm getting good (high saturation) color
> is when I'm working with a very "used" set of chemicals (I'm using 2 oz
> aliquots, say after 2-3 8x10's).
>
The first mistake you made was using Beseler's RA-4AT kit. ;-)
Seriously, when I got back into color a few years ago, I, too, tried the
same Besler chemistry you are using. The first kit turned out pretty
well, but the second kit was terrible. All the colors shifted, and I
couldn't seem to get much color saturation, same as you are reporting.
This, in addition to the cost, was what led me to brewing my own RA-4 from
scratch.
The problem you are encountering is due to how Beseler achieves a
room-temperature RA-4 process. They do it by adding Potassium Hydroxide
to the developer. This significantly raises the pH of the developer,
which in turn accelerates it at lower temperatures. However, while this
does allow for reduced development time per se, the excessively high pH
required for room-temp processing adversely affects how the developer
by-products form the color dyes, which is why you are not seeing the color
dyes fully bloom. I'm not certain whether this is due to the pH itself,
or if the by-product/coupler reactions are both time/temperature
dependent, or a combination of the two.
Now, as for why it seems that the "seasoned" developer produces better
results, my best guess is that it again is due to the KOH: It is a
_non-buffered_ alkali, meaning that as it is consumed the pH will lower,
causing the development reaction to slow down, and thus allowing the color
dyes to form properly. The Beseler kit also uses a substantial amount of
Potassium Carbonate as an accelerator, which _is_ buffered. So, as the
KOH is consumed, the pH will drop until the reaction has come to depend on
the Carbonate to keep it going, at which point it will have slowed down
enough to allow the color dyes to properly form. This is why some Beseler
RA4-AT kits will seemingly perform well without "seasoning," because the
KOH will slowly absorb CO2 from the atmosphere through the plastic
bottles, neutralizing it. If the kit has sat on the dealer's shelf long
enough, then enough KOH may be neutralized to where it becomes useable,
which is what I believe happened in my case with that first kit I bought
(I could almost write my name in the dust they missed wiping off).
The problem is that you are walking a tightrope: On one side, the
developer is excessively accelerated, yielding poor saturation. On the
other side, while you try to lower the pH you are consuming the CD-3 in
the developer, as well as building up halides that will slow down the
reaction even more.
>
> At this point, things look nice with the
> recommended development time. No other permutation of development/exposure
> will get results with fresh chemicals. I still don't know whether this
> "seasoning" occurs by chemical depletion on the paper, or whether it is
> simply oxidizing in the air as a process/pour. I'm stirring a small open
> container of color developer right now to try to test the later hypothesis.
>
It's the KOH being exhausted.
Another option you might try (to test my hypothesis) is to use a
controlled amount of acid to neutralize the KOH without neutralizing the
Carbonate. Prepare a 3% to 4% solution of Potassium Carbonate and measure
its pH. The measured pH will become your developer's target pH. Now,
using either a pH meter or litmus paper, add an acid, drop by drop,
thoroughly mixing, to the fresh developer until the it's pH matches the
target pH.
Use that developer on some test prints and let me know if you see any
improvement. You'll likely have to adjust the development time and/or
temperature to compensate for the missing KOH, but I suspect the results
will more than make up for the inconvenience. :-)
If it works, this would be the preferred way to go for now, because it
will slow down the reaction without consuming the CD-3. You will
therefore get more usable life out of the developer.
You will likely also see a shift towards a warmer color balance. Last
summer or two, I was trying to use CD-4 (instead of CD-3) to develop color
prints without success, and discovered that the addition of KOH tended to
cool down the color balance significantly, as well as seemingly inhibit
full dye formation. Accordingly, my hunch is that once you neutralize the
KOH out of the developer, you'll not only see warmer colors but better
saturation to boot.
>
> I am planning to move up to a "real" RA-4 system, but was trying to
> get some experience first with a cheap A.T. kit. But unless I can get some
> reliable results, I'm not too excited to spend even more money.
>
You can get great color easily, but you won't get it (IMO) using Beseler's
room-temperature kits, because of how it affects the dye formation. How
others in the ng manage to use Beseler's kit and get great (let alone
passable) results is a secret I've not yet learned.
I would heartily encourage you to consider getting a tempered rotary
processor, such as Jobo makes. They take most of the agony out of doing
color. Additionally, if you have access to a pharmacy-style or other
precision balance (+/- 0.001g), then I would suggest you consider mixing
the chemistry from scratch. Your chemistry costs will plummet if you do,
and the horrible variableness that comes with AT kits will be history.
Right now I'm working to finish up my fine-tuning of a C-41 formula, using
control strips and a densitometer to nail down all of the variables and
procedure. Once that's done (and the College fixes the Post function :)
and I get it posted to the ng, I'll then be turning my attention to my
RA-4 formula, to fine-tune it as well using control strips. The result
will be a brewed-from-scratch RA-4 kit that will exactingly nail the Kodak
reference standard (which means being able to achieve professional lab
results at home, technical/artistic printing skill notwithstanding), and
which will cost maybe $0.25 per 8x10.
If you're interested, I'll add you to the email list for when I get these
revised formulas/procedures completed. To use these formulas/procedures,
you'll minimally require a tempered rotary processor, access to a
precision balance, and a Kodak Model 3 Process Thermometer.
If you want to verify the accuracy of your process, you can do so with
Kodak control strips. They are available for both C-41 and RA-4, and will
require a transmission/reflectance color densitometer to read them. Kodak
also has on-line the manuals for how you go about using the control strips
and interpreting the results.
>
> Thanks in advance for your time, and any insight you can provide!
> -Rhett
>
My pleasure. Hope this helps you out. If you have any more questions,
please feel free to email me and I'll try to help you out.
Bill
Scott M. Clark
chemicals? I've heard good things about the Tetenal kits, and I can't
imagine that people would be happy with dull, unsaturated results.
scott
--
|: Scott Clark :| "The love of the irregular is a sign of the
|: sc...@virginia.edu :| basic quest for freedom" - Soetsu Yanagi
Lee Kanner
years, before RA4 and room temperature kits, I processed in a drum,
preheating the drum with water before the pouring in the developer. If I
remember correctly, it was a pretty well filled drum with 120 degree water
(Farenheit) and then the chemicals were used at 100 degrees.
When RA-4 and room temp kits came out, I started processing in trays, and
tripled to quadrupled the rate at which I could turn out prints. I had
success with both Beseler and Jobo (Tetenal), but settled on the latter
because the solutions were ready mixed and just needed dilution.
Admittedly, I used Beseler only once (with success), so my good experience
does not necessarily contradict your bad one. I have however used perhaps
ten Jobo kits for what amounts to hundreds of kits and have always gotten
beautiful results.
The one problem I had with working in total darkness was moving the wet
print from the developer tray to the stop bath. For the serious baths, to
conserve money, I use 8 x 10 trays for 8 x 10 paper. I solved the stop
bath problem by recognizing that acetic acid is cheap and using a very
large tray for that. So, I don't have to worry about my aim in the dark
when I fling the paper into the stop bath. And, after twenty seconds
therin, I can turn on the lights.
Try the Jobo kit and do try tray processing. If you're not a complete
dork at working in the dark, you'll be converted.
Herb
In article <cryorunner-07...@dt082nd8.san.rr.com>,
--
Herb and/or Lee Kanner
For e-mail reply, replace "acmd" by "acm"
Francis A. Miniter
Very interesting. Do you find oxidation of the developer in the tray to be a
problem?
Francis A. Miniter
John Costello
Rhett,
I use the Beseler RA4-AT in a Nova Quad. The RA4-AT used to come with just two
solutions, but recently they changed to a five solution kit which is supposed
to be be more environmentally friendly. After going through at least 30 or 40
2.5L kits, which represents at least 2000 prints including 8x10 and 11x14 I
have never had a problem with either the old or new formulation. Since the
Nova has temperature control, I use the chemistry at 77F. Temperature control
may seem like overkill for RA4-AT but it establishes what I consider more
important than any absolute values; namely, consistency. I have found that
consistency in color work is the holy grail. At 77F I develop for 45 sec, stop
bath for 20 sec. and blix for 45 sec.
One caveat: I have found that the bleach dies sooner that the developer -
probably due to contamination from the developer and stop bath - so it has to
be replenished at a higher rate.
Maybe I have just been lucky - or maybe I have really just gone color blind
since I went on Medicare three years ago!
I hope you can resolve your problem.
John
Lee Kanner
First, about Beseler changing the format. The Beseler kit which came in
two solutions was the kit made by Tetenal in West Germany, and imported by
Beseler. Then for reasons I know not, Beseler dropped Tetenal or was
dropped by Tetenal. Jobo now imports the Tetenal kit, which is exactly
the same kit as the former Beseler kit. Beseler then found a U.S.
chemical house which developed the kit they currently sell.
My arguments about thin emulsion and over development hold. As long as
you overdevelop slightly, you can get totally reproducibly results at a
range of temperatures. In my tray processing, the temperature has ranged
from 70 degrees to 73 degrees, with corresponding *minimum* processing
times of 70 seconds to 50 seconds. I would say that my practise has been
to allow rougly an extra ten seconds, which is usually spend letting the
developer drain from the print before tossing it in the stop bath.
My results with the new Beseler kit and with the Tetenal kits have been
comparable. The only really interesting fact is that when switching kits,
I had to make significant changes in color filtration.
Read my previous post. I talk about reproducibility.
Herb
Rhett James Barnes
in my footsteps.
I gave up fighting with the Beseler RA-4 AT kit, and never got any reply
to my questions E-Mailed to them. So I broke-down and got a "real" (not
ambient temperature) RA-4 gallon set from Kodak. Things were immediately
better. After stopping down about one-stop for the new developer, I
immediately got great results.
I'm still working at 30 deg, because I've been having trouble with the
fish-tank heaters that I was trying to use (I'm getting a real heater ASAP
to go to the "normal" 35 deg).
As long as you keep some warm water handy, the Kodak kit is just as easy
as the Beseler, and produces results that are not even comparable to the
Beseler kit I had. It's also about 1/3 the cost with the suggested
utilization rate, though I've used it about twice that rate without seeing
any effect so far (or "for non-critical applications" as they say).
The only issue that I might see that the blacks may not be as deep as they
could be, with a very slight blue tint. But after inspecting the prints,
I'm not sure I see this. It looks like there's actually detail there, as
opposed to just light-blacks, so maybe the contrast is just a little bit
less than the "good" print I had gotten by depleting the Beseler
chemistry.
So, the moral for anyone just starting and wanting to get into color
printing, don't be afraid of the "real" RA-4 chemistry. I know that
people have gotten acceptable results from the Beseler AT kit, and people
here seem to like the Tetenal AT kit. But just from my personal
experience, the Beseler RA-4 AT kit I bought was a waste of money; the
regular Kodak RA-4 produced results that blew them away. It's not a
subtle difference, it's night-and-day. And it's not really that hard to
get to the lower temps given by Kodak for the "regular" RA-4 ($15
BI-METALIC fish-tank heater and a $14 circulator, though maybe being that
cheap wasn't really worth it in the end).
Thanks to everyone for their input here. And as you can see from the
postings here, my results may not be typical; your mileage may vary.
-Rhett
KHOwen
>white. And considering that the neg was Ektar, the color corrections
>weren't that bad (90Y 50M). I first tried on Kodak Supra III, then jumped
>to Fuji C.A. type C in hopes of getting better color. But it didn't
>help. Not completely horrible where I could know something absolutely had
>to be wrong, just not nice enough to inspire me to ever want to print
>anything.
> As a
>begin to reduce the Color Dev time, I seemed to be getting better and
>better color saturation. I added a stop bath to help reduce the time.
>Finally I got a really awesome test print
I work for Jobo Fototechnic, the USA distributor of Tetenal chemicals, so
please consider my comments accordingly.
There are a couple possibilities that fit your description. Since you adjusted
your color developer time and got improvement, that's the first place to check.
If you are over-developing, it can cause the whites to get a little gray, or
even tend toward yellow. This is basically a high base + fog condition.
The other problem could be underactivity in your bleach/fix causing retained
silver in your print. This also causes low contrast and generally muddy
looking prints. Try doubling your bleach/fix times. It can't hurt, and might
solve the problem.
Ken -- Jobo USA
sa...@jobo-usa.com
Jobo web site: http://www.jobo-usa.com