From: Jeff Buck (jeffbuck@swcp.com)
Date: 09/22/02-12:13:34 PM Z
Thanks. There's one point here where we didn't communicate, viz., the
question of increased stain w/ plus development. I'm not talking about
general stain; I'm talking about image stain. The unexposed film edges
remain clear. -jb
At 01:50 PM 9/22/2002 -0400, Sandy King wrote:
>Jeff,
>
>Comments to your disadvantages.
>
>
>>Sandy: Disadvantages:
>
>
>
>> (1) Toxicity. I believe I have this well under control in my work
>> environment, but I don't think it can be discounted completely. And I
>> do have a cigar pretty much every evening (for crying out loud).
>
>
>This is mostly a crock. Mix your solutions in a well-ventilated area and
>use gloves if you tray process and so much for that. Most other reducers
>are also toxic to varying degrees, and everyone should use gloves anyway.
>
>> (2) The difficulty of determining the density range of pyro
>> negatives. I don't want to spend hundreds on a densitometer and, even
>> if I did, I've heard a range of opinions on the point of doing so (I
>> guess the blue channel of a Mantis is supposed to be pretty good
>> ...). Still, it would be really nice to be able to use the
>> simple/elegant method described by Weese & Sullivan (two cards with
>> holes -- one goes over the negative, the other goes over a Stouffer
>> strip, etc.), but this ain't going to work with a pyro stained negative.
>
>The simple method described by Sullivan and Weese works just effectively
>with a pyro stained step wedge as with a traditional one. And since you
>need to do your own film testing anyway it really makes no difference in
>end for this method whether you used a stained or traditional negative.
>
>Now, if you are really into sensitometry and using a densitometer, as is
>Dick Arentz, (and me also for that matter) the stained negative does
>present some problems in reading, and this will vary according to the
>printing process and exposing light source. It is not good enough to just
>read through the blue channel by itself to get an effective DR. But if you
>really calibrate all your real negatives with your real printing process
>and procedures (as you know you should anyway), a reading of your negative
>through the blue channel will accurately reflect printing density.
>
>
>> (3) Long exposure times printing w/ pt/pd due to the UV-blocking pyro
>> stain. I believe this sacrifices smoothness in the image. Now, I've
>> covered this to a large extent by changing to a powerful metal halide
>> light printer (1000W, 5200K). I haven't seen a printing time over 13-14
>> minutes, which would be a VERY much longer printing time under black
>> lights (for instance).
>
>
>Exposing times are primarily determined by shadow density, which with a
>pyro stained negative shows the least proportionate stain. The difference
>in actual reading between my traditional negative and pyro stained
>negatives from log 0.15 to log 0.45 is almost always less than log 0.07,
>which is less than 1/2 stop of additional printing speed.
>
>Most of the increased proportionate stain is in the highlights, which as
>you know must be controlled by the contrast control procedures of the
>process, not by printing time.
>
>
>> Also, I've learned to minimize general stain. Still, I get quite
>> puzzled sometimes. On the one hand, a guy is comparing my pyro neg to
>> his and saying, "See how yours has so much more dang image
>> stain?!" Well, I thought getting strong image stain was the whole point
>> of the stuff.
>
>No, no, and a thousand times no. Increase general stain is just garbage
>that leads to increased exposure times since it is in the shadows as well
>as the highlights. What you want is proportionate stain, very little in
>the shadows, increasing slightly in the mid-tones, and greatest in the
>hightlights.
>
>
>
>>This is connected to another phenomenon: As I apply plus, plus-2 and/or
>>plus-3 development with WD2D or PMK on FP4+, I get the desired density in
>>the highlight areas (quite predictably) but I also get more and more
>>aggressive image stain. -jb
>
>
>I suspect that you are not adjusting for effective negative speed when
>exposing in N+ situations. As you increase time of development effective
>negative speed also increases, and quite significantly. Depending on film
>an increase of up to 2X or 3X the effective speed of the film is not
>uncommon. And FP4+ is one of the films that responds most in terms of a
>speed increase with increased development times. If you don't compensate
>for this the result will be greatly increased density in the shadows,
>which you don't want since you 1) don't need it, and 2) it can cause a
>huge increase in printing time.
>
>Sandy King
>
>
>
>
>
>
>>
>>At 10:31 AM 9/22/2002 -0400, Sandy King wrote:
>>>Jeff Buckels wrote:
>>>
>>>>I tried something like this inquiry a month or so ago and got no
>>>>response. Perhaps on this occasion some of the more indulgent members
>>>>of the list are checking their email:
>>>>
>>>>Let's say that I don't give a flying flip (note the carefully-crafted
>>>>euphemisms, Gordon) how my negatives would work for silver printing
>>>>(hence, I don't care whether my negatives will work both for silver and
>>>>pt/pd)..... In that case, what is the justification for bothering with
>>>>pyro? Assume as well that I reject the Great Separation in the High
>>>>Values justification (Dick Arentz seems to reject it; surely I know no
>>>>better than he) and that, while I appreciate the economy of pyro, I
>>>>doubt that the economy alone offsets the disadvantages of pyro. So,
>>>>there then -- Why use pyro?
>>>>
>>>>Jeff Buckels
>>>
>>>I resisted comment the first time around on your inquiry because threads
>>>on pyro tend to become something of a quagmire. Some attribute almost
>>>magical qualities to pyro developers while others are perfectly
>>>satisfied with the results they get with the traditional developers they
>>>have used since they first started doing photography and apparently see
>>>no need to change. Nothing, and I repeat *nothing* we say here is going
>>>to change any of that for these people. However, I am curious as to what
>>>you see as the disadvantages of pyro? As someone who uses both
>>>traditional and pyro developers I have some thoughts of my own on this,
>>>but wanted to first see what you, or others, perceive as real
>>>disadvantages with pyro.
>>>
>>>
>>>Sandy King
>>>
>>>
>>>
>>>
>>>--
>
>
>--
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