Pyrocat and semi-stand for extreme contrast compensation
I have been using PMK Pyro for about the last 6 motnhs now and absolutely adore the quality i get from it. I've been using it with 120 Tmax 100 and my Mamiya 7 and the results are extraordinary.
I am moving up to 4x5, and I am trying to find a developer to use as a compensation developer, in extreme contrast situation (i.e 8 stop range and up). I am stuck on the pyro, so pyrocat seems like the best bet for a semi-stand compensation development. I am not worried about the high acutance, since it is already one of the reasons I am part of the cult that is pyro. Does anyone have semi-detailed or detailed procedure to use as a starting point for 4x5 tank semi-stand/minimal agitation for Tmax 100 film in Pyrocat HD. Do I shoot the shadows at a zone V or stick with my regular II or III, times, temps, dilution, agitation method, etc. I have searched far and wide and haven't been able to find much thats of a huge help, even on unblinkingeye. Anything helps, thanks for any replies.
P.S-Maybe Mr. King will drop his knowledge?
Search here. There is a thread with an outstanding sample attached. I have read the whole thing. Right now I can't recall the details. The developer was a pyro flavor of some sort. Not sure if it was Pyro-HD. Yes, maybe Sandy King will be along.
Search stand, semi-stand. It's here somewhere.
I do a lot of development for extreme compensation with Pyrocat-HD. I don't have any data for Tmax-100 with this method of development but you migh find the thread that I started for Fuji Acros useful as development times should be about the same as for TMAX-100. .
Basically, what I do is extreme minimal agitation, or four total agitation cycles, the first very vigorous for one minute, the other three for 10 seconds at the 1/4, 1/2 and 3/4 point of total development time.
Thank you for the help Venchka and Sandy. I knew that the info had to be somewhere in the endless lists of threads. For Sandy, and anyone at that, I use the Zone system, expose for shadows, over or under develop for your highlights by 20% or more depending on range. I see you have the BTZS numbers, which i'm not familiar with. Is the SBR the same as my range between shadows and highlights. For example, if my shadow reads an EV 4 on my spot meter, and my highlight reads an EV 13, is this the same as a 9 SBR. Or 4 and a 14 EV the same as a 10 SBR? I read some info on it and it seemed like there was lots of calculating involved, and i wasn't sure if i was making it too complicated or if I needed to recalibrate, i which case I'd probably just retest on my own using the regular AA zone system. Thanks for your answers and I can't wait to jump in to large format.
To determine SBR take an incident reading in the shadows, with the meter pointed toward the camera, and then one in the brightest part of the scene, again with the camera pointed toward the camera. Subtract shadow reading from highlight reading and add to five for SBR. For example, if you read EV 9 in the shadows and EV 12 in the highlights, subtract 9 from 12 and add the 3 to 5 for an SBR of 8.
Originally Posted by degodan9
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Thanks Sandy... well said, and also admirably summarized in Phil Davis's book. It is a shame that much of what the late Phil Davis wrote and taught has been subsumed in the understandable emphasis on the more traditional "zone system". This thread is neither the time, nor the place, to talk about Beyond the Zone System ( as taught by Mr. Davis ), and the possible advantages of incident metering. Suffice it to say that the entire matter of SBR is well summarized and analyzed by Mr. Davis in his book. IMHO, BTZS will most certainly become appreciated as a classic text.
FWIW here are my notes from my initial tests for extreme SBR. I ended up using HP5 because for similiar SBR, FP4 exposures were 20 minutes plus. Notice my dilution. Though Sandy and other's advised against using it that dilute I had no problems. This is for my 8 x 10 negs in tube for printing on AZO. So I may have more development than you would require. The initial water bath is to make it easier the place the film in the tube.
Doyle Hotel negative 20
9ml-6ml-70 ounces pyrocatHD
1 minute water bath in tray move to tube for 5
minute water bath in large tube with vigorous and
1.5 minute initial agitation invert after 45s
6.5 minute stand
out 4 times invert (15 seconds)
6.5 minute stand
out 4 times invert (15 seconds)
6.5 minute stand
development is even
density = 1.61
upper wall = 1.1
zone III = 0.36-0.47
zone III to wall = 0.63
For initial tests I suggest using two negatives of the same scene and adjusting the time for the second negative depending on your initial results.
So I think I have this figured out, considering the circumstances. Those being:
Money is always a factor, I'm a 20 year old college student trying to get by. So buying a good quality incident meter isn't really an option, nor is diving into the money that BTZS stuff is worth. Plus, I've had great results with the AA System, and if it ain't broke don't fix it. No offense to Mr. Davis or any of his followers. Where it is broke is for the extreme contrast situation, since less than a 5 min development time for most films can create problems that I am trying to avoid. My plan is to kind of use a makeshift BTZS system and Pyrocat for cases where my highlight/shadow range is more than 7, since I can handle anything under that using the AA Zone System and tests I have already ran.
1. I am using a Pentax spot meter. I found a formula here on APUG for using spot readings to find SBR. It is SBR = (7*(D-N))/D, with D being my range between shad and high, and N being my N-1, +1, etc etc. If I can get some clarification that this is a true workable formula, then I'm a happy camper.
2. Sandy King has posted times in a previous Acros forum for Pyrocat at 1:1:100, agitating for the first minute, and then 10 seconds at 1/4 time, 1/2 time, and 3/4 time at 70F. They are as follows:
SBR ---Time of Development in Minutes
10---- 9 minutes
9 -----12 minutes
8 -----14 minutes
7 -----20 minutes
6 -----29 minutes
As per Sandy's suggestions earlier, TMAX 100 and Acros are fairly similar. And again, since I am going to try a makeshift BTZS system, some film tests are in order. I am obsessive, and if I can make reproducing results a science, then tests are okay with me.
3. My last quibble is when using SBR, do I still expose for my shadows. I.E, if my meter reads my shadow to a EV 4, do I bump that 4 down to to a zone III on my dial and use any of the combos for that, or should I keep it at a zone V. I ask this because at times I have used TMAX devloper, very diluted, minimal agitation for highlight compensation, and I had to shoot the shadows at a zone V for them to come out. Once I have this figured out, I just have the testing to go and I am off and running. Sorry for the length of this, but I figured the combination of everyones wonderful posts and answers could be of service to others, as it has been so far for me.
P.S- I am not in any way trying to get into the debate of Zone System vs. BTZS. I am just trying to find routes to get the best pictures I can in any situation that the earth throws at me. Most of this info will be used in my case in landscape photography, and mother earth is known to throw curveballs. I'm trying to hit a home run with them. It seems like BTZS is a great system, but I'm for the most part in the zone (no pun intended) with the AA system. I love photography because every time I think I have a grasp, I find out how little I know.
Last edited by degodan9; 01-02-2009 at 04:04 AM. Click to view previous post history.
The ZS is quite well suited for handling very high SBR's as is BTZS (I would assume b/c I don't use it)-----so perhaps you could shed some light on the reason for using one system for higher SBR's and another system for lower SBR's.
Originally Posted by degodan9
With due respect, regardless of what developer you have in mind, I suggest you decide what system you are going to use, either the ZS or BTZS. It seems you are unduly complicating things for yourself. I'm not a user of BTZS but I believe it does not employ the use of a spot meter to determine the SBR (it uses incident readings), whereas the ZS does. The formula you mentioned is not used in the ZS, as there is no need for such a thing so I'm assuming it refers to the other method, IDK.
To address two of your questions.
"My last quibble is when using SBR, do I still expose for my shadows. I.E, if my meter reads my shadow to a EV 4, do I bump that 4 down to to a zone III on my dial and use any of the combos for that, or should I keep it at a zone V."
When we base exposure on an incident meter reading taken in the shadows we should decrease the indicated exposure by one stop. I simply rate the film for twice the nominal ASA, as recommended by Davis. For example, when metering this way I rate TMY at EI 800, not 400.
Another method of metering is to take an average of the shadow and highlight readings. For this, rate the film at its normal ASA, for example rate TMY at 400.
"Money is always a factor, I'm a 20 year old college student trying to get by. So buying a good quality incident meter isn't really an option, nor is diving into the money that BTZS stuff is worth. Plus, I've had great results with the AA System, and if it ain't broke don't fix it."
Bear in mind that BTZS is not something entirely different from Zone system, but an extension of Zone. Phil Davis himself was of the opinion that Zone metering offered potentially greater creative control than incident metering, but that incident metering was more consistent for most scenes. In any event, with both systems exposure is based on shadow value readings, whether they are made with an incident or spot meter. When I run a curve with Winplotter it gives me values for both Zone metering, or N values, and BTZS, or SBR values. There are clearly some situations, far away scenes for example, where Zone metering gives better results. It helps to understand and use both systems.
Last edited by sanking; 01-02-2009 at 01:04 PM. Click to view previous post history.