Example of Semi-Stand vs Tray processed 7x17 negative

[Steve Sherman]

Explanation of negatives made in the very beginning of experimenting with the Semi-Stand method of film processing 11 years ago:

Two sheets of 7x17 FP 4 film identically exposed less than a minute apart. One of the sheets was tray processed in ABC Pyro for 24 minutes @ 1-1-1-7 which yielded a density of 1.79
The other sheet was processed using a Semi-Stand method, 5 minute presoak, 2 minutes initial agitation and 1 minute agitation @ 30 minutes in Pyrocat HD @ 1-1-175 in a large tank. Total development was 60 minutes, density of 1.33

Each negative was scanned on an Epson 750 scanner @ 600 DPI with emulsion facing up, opposite sides of the two separately processed negatives were stitched together via CS 4 with no manipulation or sharpening of any kind other that converting to grayscale.

Cheers !

[Lachlan 717]

ABC on the left/HD on the right?

[Bill_1856]

I only get ONE image.

[Lachlan 717]

I only get ONE image.

It's stitched down the middle.

[Steve Sherman]

ABC on the left/HD on the right?

Two separate negatives, one processed in a tray the other using the Semi-Stand method of film processing then opposite sides stitched together. The SS neg on the left side @ 1.33 density and the right side tray processed neg @ 1.79 density

[Ironage]

The left side is definitely better. Thanks for sharing this.

[Peter De Smidt]

Steve, how is the negative held in the large tank? What type of agitation?

[Michael Kadillak]

I am impressed that you could get anything out of FP4+ and ABC pyro. This combination for me was a complete disaster which could have been the water or ? In dilute pyrocat FP4+ rocks. The other benefit of this process is the increased film speed. I shoot FP4+ as well as aged original TMY at full film speed which is a 2X improvement over what I exposed TMY with in ABC. With ULF every little bit of film speed is a huge benefit in the field when filters and/or bellows corrections are deployed.

Clearly the high acutance associated with the semi stand development is exemplified in this image. I use Home Depot PVC tubes as my tanks and they work great. Hard caps glued on the bottom and soft caps on the top with some room to exchange the developer during the agitation period.

[Steve Sherman]

Steve, how is the negative held in the large tank? What type of agitation?

Peter, back in the early days I used a large can which held 4400 ml of solution. In the very beginning I used a stirring motion to agitate, big mistake, increased density at the bottom of the neg, went to a plunging action like a washing machine and that cured some of the initial agitation hurdles. 4400 ml for one 7x17 "piece of film was not efficient in spite of the low cost of PyroCat HD. I now use 3" Grey Electrical conduit (plastic). A terrific idea devised by my good friend Tim Jones (climbabout) a 7x17" piece of film requires 2400ml to process and I use an version method of agitation. Usually, 2 minutes initial agitation for most normal contrast scenes. However, most of my photography is done under unusual lighting conditions and there in lies the real reward with this type film processing.

Michael, while I have never tested the "White" PVC tubes I have been lead to believe there are not opaque like the Black ABS is, just a word of caution. The rest of my tube setup sounds very similar to Michaels with the glued bottom piece and a removable cap on top. The one word of caution I would offer for those who chose to make their own, the amount of "free" space above the film is necessary as some solution does leak out during inversion, that space can not be so much as to not allow your hand to get down to grab the neg once the processing is over. I only put developer in the tube, remove to stop and fix in trays in the dark.

The ABC Pyro was chosen as it has the reputation of being the most aggressive and yielding a high density which is exactly what I wanted to illustrate with this comparison. The Pyrocat neg @ a density of 1.33 has considerably greater micro contrast than the ABC neg @ 1.79 density, conventional thinking would be the exact opposite to be the case.

In posting the pix to the forum I see that it is automatically converted down to 25.7 KB which does not begin to allow any of you to really get a feel for how dramatic the difference is with these two negatives that have been stitched together.

[sun of sand]

Can you stitch them the opposite way for real comparison now?
Left side has the detail and interest to begin with
Who knows what focus issues were present etc

[Peter Lewin]

Steve: Hopefully this question has an answer that can be summarized, for those of us unfamiliar with semi-stand processing. I typically tray develop 6 4x5 negatives at a time in one liter of Pyrocat-HD using the traditional shuffle method. If I wished to gain the benefits of semi-stand (based on your example negatives), first, am I correct I would need 6 PVC tubes, with one negative in each tube, and second, what would be the total amount of working developer solution (it sounds as if you have to fill each tube to capacity)? (I'm not looking for a complete description of the semi-stand process, just enough of an idea to see if I want to follow this further.)

[Michael Kadillak]

Peter, back in the early days I used a large can which held 4400 ml of solution. In the very beginning I used a stirring motion to agitate, big mistake, increased density at the bottom of the neg, went to a plunging action like a washing machine and that cured some of the initial agitation hurdles. 4400 ml for one 7x17 "piece of film was not efficient in spite of the low cost of PyroCat HD. I now use 3" Grey Electrical conduit (plastic). A terrific idea devised by my good friend Tim Jones (climbabout) a 7x17" piece of film requires 2400ml to process and I use an version method of agitation. Usually, 2 minutes initial agitation for most normal contrast scenes. However, most of my photography is done under unusual lighting conditions and there in lies the real reward with this type film processing.

Michael, while I have never tested the "White" PVC tubes I have been lead to believe there are not opaque like the Black ABS is, just a word of caution. The rest of my tube setup sounds very similar to Michaels with the glued bottom piece and a removable cap on top. The one word of caution I would offer for those who chose to make their own, the amount of "free" space above the film is necessary as some solution does leak out during inversion, that space can not be so much as to not allow your hand to get down to grab the neg once the processing is over. I only put developer in the tube, remove to stop and fix in trays in the dark.

The ABC Pyro was chosen as it has the reputation of being the most aggressive and yielding a high density which is exactly what I wanted to illustrate with this comparison. The Pyrocat neg @ a density of 1.33 has considerably greater micro contrast than the ABC neg @ 1.79 density, conventional thinking would be the exact opposite to be the case.

In posting the pix to the forum I see that it is automatically converted down to 25.7 KB which does not begin to allow any of you to really get a feel for how dramatic the difference is with these two negatives that have been stitched together.

My apologies for being quick to get off a response. The tubes I use are indeed BLACK plastic and clearly are ABS plastic as you mentioned and not the white ones that are PVC. My bad. To many things going on today.

I find that it is much easier take the film out of the tubes before pouring out the developer. this is my ULF set up. When I have a big lot of 8x10, 5x7 or 4x5 that I want to knock out quickly I use my 3.5 gallon burst tank and Kodak hangers and it works perfectly. I can do 6 8x10's in one run or 12 5x7's or 24 4x5 negatives or various combinations of formats as necessary.

[Steve Sherman]

Steve: Hopefully this question has an answer that can be summarized, for those of us unfamiliar with semi-stand processing. I typically tray develop 6 4x5 negatives at a time in one liter of Pyrocat-HD using the traditional shuffle method. If I wished to gain the benefits of semi-stand (based on your example negatives), first, am I correct I would need 6 PVC tubes, with one negative in each tube, and second, what would be the total amount of working developer solution (it sounds as if you have to fill each tube to capacity)? (I'm not looking for a complete description of the semi-stand process, just enough of an idea to see if I want to follow this further.)

Hello Peter, I have 5 tubes for 5x7 film and don't believe I've had more that 4 going at once. My methods maybe a bit unusual when compared with other large format shooters. First, I shoot in unusual lighting situations which dictate vary different development schemes. Rarely do I have 3 or more same development sheets of film at one time, that said even if all your film called for one specific devlopment it would be difficult to develop more than 4 at the same time.

The other night I developed 7 sheets of 5x7 film and one sheet of 7x17 film, the session including washing aid and final wash took approximately 3 hours. Clearly multiple sheets in a tray for 8-10 minutes will require much less time.

However, the lighting conditions I control and the results I am able to realize continue to out weigh any time saving factor. Fortunately my photography interests do not dictate large amounts of film for processing.

As far as volume of solution, a 5x7 tube holds 800ml and depending on scene contrast can be as little as 4 ml of A and 2.75 ml of B. A Normal Development dilution would be 5-3-800ml for 26 minutes. With HP5 adjustments to the ratios must be made so that the B component of Pyrocat never a goes below 4ml.

Hope this helps, do give the process a try so that you may see first hand the results that are possible

[Steve Sherman]

[QUOTE=sun of sand;1249798]Can you stitch them the opposite way for real comparison now?
Left side has the detail and interest to begin with
Who knows what focus issues were present etc[/QUOTE

First, I find any JPEG I have every uploaded to the LF forum is converted down to 25.7 KB. An extremely small file with little opportunity to really see the striking difference in the stitched file that I shared. Second, the scene is from an overlook at least a 1/2 mile from the canyon walls so focus is not an issue nor was wind or any other image degrading factor.

Your question sugggests you may have never seen a negative or resulting print from this process, it's worth a look !

Cheers.

[Peter De Smidt]

Steve,

Thanks for the comparison image, as well as the detailed info.

[William Whitaker]

Peter, back in the early days I used a large can which held 4400 ml of solution. In the very beginning I used a stirring motion to agitate, big mistake, increased density at the bottom of the neg, went to a plunging action like a washing machine and that cured some of the initial agitation hurdles. 4400 ml for one 7x17 "piece of film was not efficient in spite of the low cost of PyroCat HD. I now use 3" Grey Electrical conduit (plastic). A terrific idea devised by my good friend Tim Jones (climbabout) a 7x17" piece of film requires 2400ml to process and I use an version method of agitation. Usually, 2 minutes initial agitation for most normal contrast scenes. However, most of my photography is done under unusual lighting conditions and there in lies the real reward with this type film processing.

Michael, while I have never tested the "White" PVC tubes I have been lead to believe there are not opaque like the Black ABS is, just a word of caution. The rest of my tube setup sounds very similar to Michaels with the glued bottom piece and a removable cap on top. The one word of caution I would offer for those who chose to make their own, the amount of "free" space above the film is necessary as some solution does leak out during inversion, that space can not be so much as to not allow your hand to get down to grab the neg once the processing is over. I only put developer in the tube, remove to stop and fix in trays in the dark.

The ABC Pyro was chosen as it has the reputation of being the most aggressive and yielding a high density which is exactly what I wanted to illustrate with this comparison. The Pyrocat neg @ a density of 1.33 has considerably greater micro contrast than the ABC neg @ 1.79 density, conventional thinking would be the exact opposite to be the case.

In posting the pix to the forum I see that it is automatically converted down to 25.7 KB which does not begin to allow any of you to really get a feel for how dramatic the difference is with these two negatives that have been stitched together.

Never having attempted semi-stand development, I am having a hard time visualizing all of this, Steve. Some pictures would be a great help. A video would be super!

[Steve Sherman]

Never having attempted semi-stand development, I am having a hard time visualizing all of this, Steve. Some pictures would be a great help. A video would be super!

Hello Wil,

I have managed to upload several stitched scans of 7x17 negs. These scans are done @ 600 DPI with film facing up (avoid Newton Rings) They have been converted to Grayscale and outputs were matched in "Levels" No sharpening or other corrections have been made to these files.

http://www.steve-sherman.com/newworkpg01.cfm

Lighting conditions varied from harsh mid day light (Island in the Sky) to dusk light (Palouse Canyon) to soft light ( Virgin River ) Michael A Smith saw a finished print to the Virgin River and noted the print looked so sharp it appeared "Fractured" and noted in looked "unphotographic"

The increased sharpness is secondary to the creative possibilities the process affords once it is mastered, virtually any lighting condition can be controlled.

I was not able to upload the example I used on the forum, there was a web site coding error which demands I contact the designer to correct.

Thx for your interest.

[Wayne]

pardon my ignorance, but why did you use a tank for one and tray for the other? Might this have introduced variables other than developer/stand?

[William Whitaker]

Hello Wil,

I have managed to upload several stitched scans of 7x17 negs.

Thanks for your hard work Steve. I was referring to the actual process itself, especially the tubes and agitation procedure. Is electrical conduit of the size required available at somewhere like Home Depot or must it be purchased from an electrical supplier (more expensive, especially if there is a minimum quantity).

I am interested in your procedure particularly as it would relate to ULF development.

Thanks again.

[John Jarosz]

I get it now. Nice way to show the difference.

Tough spot to photograph from. It's a very intimidating place.

[Steve Sherman]

pardon my ignorance, but why did you use a tank for one and tray for the other? Might this have introduced variables other than developer/stand?

Hello Wayne,

The test was designed to show the difference between constant agitation in a tray and Semi - Stand where agitation happens only once at the mid way point. 10 years ago my understanding of Pyro was less than it is now, nevertheless ABC is still considered a highly energized developer as opposite to Pyrocat HD both of which are Pyro based. The Reduced Agitation or Semi - Stand method clearly produced much higher micro contrast even with a considerably less dense negative.

Cheers

[Steve Sherman]

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Thanks for your hard work Steve. I was referring to the actual process itself, especially the tubes and agitation procedure. Is electrical conduit of the size required available at somewhere like Home Depot or must it be purchased from an electrical supplier (more expensive, especially if there is a minimum quantity).

I am interested in your procedure particularly as it would relate to ULF development.

Thanks again.

Hello Will,

These are the pix of my tubes for 7x17" film. The same tubes of appropriate size are used for 5x7" film. I no longer screw a corresponding tube on top rather I just presoak in the same initial tube and dump the water and pour in the developer and cap with a round cap which is light tight. After an initial agitation of several minutes I reorient the film and turn on the white lights and begin prepping another tube for processing another sheet of film.

I know of many photogs who use Home Depot black "ABS" tubes which are very inexpensive, albeit not quite as refined a plastic as the electrical conduit which is still rather inexpensive relatively speaking. Caution, white "PVC" is said to be NOT opaque so that should not be an option as an FYI. Even with the grey Electrical tubing I used a "cylinder hone" to debur the inside walls of the tubes. The 3" diameter works perfectly for 7x17" film as well as 5x7" film.

Cheers

[Andrew O'Neill]

I have always preferred semi-stand over stand when using pyrocat-hd. I also use tubes.

[William Whitaker]

Thanks Steve.

[Wayne]

That's why I wonder why you changed from tray to tank as well as from constant to semi-stand. This introduces another variable. Is there a reason you can't do both in a tray?



Hello Wayne,

The test was designed to show the difference between constant agitation in a tray and Semi - Stand where agitation happens only once at the mid way point.

Cheers

[Steve Sherman]

That's why I wonder why you changed from tray to tank as well as from constant to semi-stand. This introduces another variable. Is there a reason you can't do both in a tray?

Hi Wayne,
The one time I tried semi stand in a tray all things being equal, dilution, developer and agitation the resulting density of the negative was extremely weak and therefore I abandoned that orientation of processing film in all future trials.

[William Whitaker]

...back in the early days I used a large can which held 4400 ml of solution. In the very beginning I used a stirring motion to agitate, big mistake, increased density at the bottom of the neg, went to a plunging action like a washing machine and that cured some of the initial agitation hurdles. 4400 ml for one 7x17 "piece of film was not efficient in spite of the low cost of PyroCat HD. I now use 3" Grey Electrical conduit (plastic). A terrific idea devised by my good friend Tim Jones (climbabout) a 7x17" piece of film requires 2400ml to process and I use an version method of agitation. Usually, 2 minutes initial agitation for most normal contrast scenes. However, most of my photography is done under unusual lighting conditions and there in lies the real reward with this type film processing.

Okay, so let me see if I've got this... The 7x17 film is loaded by rolling it along the long axis, emulsion-in, and inserted into the conduit developing tube. After pre-wash (or not), developer is poured into the top of the tube and the tube filled so as to cover the film. Then the tube is capped and the tube inverted end-over-end to agitate for 2 minutes after which it's set on its end to "stand" until the next step.

Sorry to be pedantic, but I find it very easy to get lost in step-by-step instructions (including those on bottle labels).

Is the developer used as a one-shot or have you found you can re-use it for another negative? In my case (for 12x20), I would require a tube about 4" in diameter and I calculate that I would need just over 4 liters of developer working solution, which seems a tad extravagant for one negative. As far as the tube goes, it looks like 4" nominal PVC conduit would work, although I've not tried to source it yet nor have determined a price.

And one more question: WRT the last sentence of the quote above, what sort of lighting conditions benefit from this method of film processing?

Thank you again for sharing your findings Steve!

[Michael Mutmansky]

Michael, while I have never tested the "White" PVC tubes I have been lead to believe there are not opaque like the Black ABS is, just a word of caution. The rest of my tube setup sounds very similar to Michaels with the glued bottom piece and a removable cap on top. The one word of caution I would offer for those who chose to make their own, the amount of "free" space above the film is necessary as some solution does leak out during inversion, that space can not be so much as to not allow your hand to get down to grab the neg once the processing is over. I only put developer in the tube, remove to stop and fix in trays in the dark.



Definitely not opaque! However, it would be possible to paint them with something to make them better, or completely opaque. Black Plastidip comes to mind.

The grey electrical conduit PVC may be, I don't recall if I tested them or not. I wouldn't count on it without testing. They aren't available in the large diameters of the white PVC or black ABS, however, but as SAteve says, they will work in the 3" diameter for the 7x17 sheets.


---Michael

[Steve Sherman]

Okay, so let me see if I've got this... The 7x17 film is loaded by rolling it along the long axis, emulsion-in, and inserted into the conduit developing tube. After pre-wash (or not), developer is poured into the top of the tube and the tube filled so as to cover the film. Then the tube is capped and the tube inverted end-over-end to agitate for 2 minutes after which it's set on its end to "stand" until the next step.

Sorry to be pedantic, but I find it very easy to get lost in step-by-step instructions (including those on bottle labels).

Is the developer used as a one-shot or have you found you can re-use it for another negative? In my case (for 12x20), I would require a tube about 4" in diameter and I calculate that I would need just over 4 liters of developer working solution, which seems a tad extravagant for one negative. As far as the tube goes, it looks like 4" nominal PVC conduit would work, although I've not tried to source it yet nor have determined a price.

And one more question: WRT the last sentence of the quote above, what sort of lighting conditions benefit from this method of film processing?

Thank you again for sharing your findings Steve!

Yes Will, you've got the description / sequence correct. Sandy King has said you can use the developer a second time, I choose not to keep this as absolutely consistent as possible.

Even at 4 liters, the amount of Cat would only be approx 30 A to 20 B per sheet. Lighting conditions in both directions, compress large amounts of contrast as well as expand very little contrast. I have developer dilutions / schemes from N - 6 to N + 5

Cheers

[Tin Can]

Well, as long as we are on 7x17, I am setting up N2 burst system for 8x10 tanks and may consider making or buying custom 7x17 tanks for N2 burst.

My system is not yet built, but I want to ask a question. I am 75% ready.

Does anybody have an opinion on vertical vs horizontal tanks for panoramic films such as 7x17 using N2 burst?

Film hangers can be made or adapted from medical equipment and I believe they use vertical tanks for all X-Ray sizes.

I might add, I have an aversion to tubes as my fingers cannot grasp the film.

[axs810]

Hmm...I don't know if this is a fair comparison for semi stand vs tray processing. How come you didn't use the same developer for both? Wouldn't that have made more sense since both sheets of film were exposed only a minute apart from each other?

[Steve Sherman]

Hmm...I don't know if this is a fair comparison for semi stand vs tray processing. How come you didn't use the same developer for both? Wouldn't that have made more sense since both sheets of film were exposed only a minute apart from each other?

Greetings,

Clearly the example can be interpreted several ways. I set out to determine whether greatly reduced agitation i.e. Semi-Stand development would yield a noticeably different negative then a continuous agitation process, in this case done in a tray.

I used the ABC formula knowing it would produce as high a density reading as most any developer. Conventional wisdom dictates the higher the density above film base plus fog the more contrast a negative would yield in the final print. Pyrocat HD was used as that has been my developer of choice for sometime leading to those trials eleven years ago.

The test proved exactly what I thought would happen, the Process of Reduced Agitation can significantly alter the micro contrast present in a given negative when compared with a tray (continuously agitated) processed negative. Thereby yielding a preception of a higher contrast negative in spite of the global contrast being lower, by a considerable amount.

The Reduced Agitation Process provides positive gains on many levels, the density necessary to produce the proper contrast in the final positive is reduced which has a direct bearing on the accutance of the negative and resulting print. The ability to compress or expand contrast by changing the dilution ratio and agitation frequency when extended amounts of time are used to exploit the effect was unheard of till this discovery, all while not sacrificing film speed at all, in fact I've found most films produce proper exposure at box speed.

Remember back to the days of single graded paper, it was always easy to control the bottom and top ends of the print, the difficult part was controlling the micro contrast or contrast between adjacent tonalities to your liking. With the advent of Multi Contrast papers that hurdle became much more user friendly. Now add the flexibility of Reduced Agitiaion Processd film and the creative possibilities are expanded to an even higher degree !

The test was always about the Process rather than the Chemistry.

Cheers.

[Michael Mutmansky]

I have to say that Steve's image comparison doesn't really do justice to the results he achieves with this process. The prints he has to show are so exquisite that it's clear he has mastery over this semi-stand process.

It's also clear that this can be taken too far, and the result starts to feel like someone just sat down at Photoshop for the first time and is in love with the Unsharp mask or possibly the HRD process! I think that Steve strikes an excellent balance between gaining micro-contrast and pushing it to the point where it is detrimental. His images don't feel manipulated to me, they feel solid, with excellent contrast, and well-realized naturally produced images, as opposed to over-cooked.

That is a credit to his workmanship skills and photography aesthetic, because this approach can be taken too far.

I'f you ever get a chance to see his images in person, do it, because they are (IMHO) the most masterfully printed silver gelatin prints that I have seen from ANY printer, alive or dead, and I've seen a lot. This is not hyperbole.

---Michael

[sanking]

"I'f you ever get a chance to see his images in person, do it, because they are (IMHO) the most masterfully printed silver gelatin prints that I have seen from ANY printer, alive or dead, and I've seen a lot. This is not hyperbole."

I agree with Michael about Steve Sherman's work. He is a true master of the silver gelatin print

Also agree with his comments about micro-contrast. It is easy to over-do this with digital, and with film from edge effects in some cases. However, with film the result is highly dependent on degree of enlargement. I personally found the procedure to be of greatest practical use with film that is contact printed. With medium format and 4X5 stand, where we usually enlarge several times, stand and semi-stand procedures can very easily get you into prickly over-done area.

That said, it is important to remember that edge effects are highly dependent on developer, and dilution, as well as type of development. The key is to use a developer, or dilution of a developer, that exhausts locally fairly quickly, and is low in sulphite. This generally calls for a developer that contains, in the working solution, a very small amount of reducer.

Sandy

[Michael Mutmansky]

Sandy is correct...

Let's add to his point that it is dependent on the amount of enlargement in that it is EXACTLY like unsharp masking in digital, or the old unsharp mask process that can be done in film (Google it if you aren't familiar), in that the effect is very context conditional. If you set up one for a particular final image size and then change the image size, you may find it to be too great, or almost insignificant.

Also, if you print in an alternate process that inherently has a long, gradual response curve (pt/pd, gum, and others), this approach can make these images jump off the paper much better than without using it, but once you have figured out what looks good in pt/pd, that negative will probably look overcooked in silver, even if it is a pyro-based negative, so be careful!


---Michael

[axs810]

Greetings,

Clearly the example can be interpreted several ways. I set out to determine whether greatly reduced agitation i.e. Semi-Stand development would yield a noticeably different negative then a continuous agitation process, in this case done in a tray.

I used the ABC formula knowing it would produce as high a density reading as most any developer. Conventional wisdom dictates the higher the density above film base plus fog the more contrast a negative would yield in the final print. Pyrocat HD was used as that has been my developer of choice for sometime leading to those trials eleven years ago.

The test proved exactly what I thought would happen, the Process of Reduced Agitation can significantly alter the micro contrast present in a given negative when compared with a tray (continuously agitated) processed negative. Thereby yielding a preception of a higher contrast negative in spite of the global contrast being lower, by a considerable amount.

The Reduced Agitation Process provides positive gains on many levels, the density necessary to produce the proper contrast in the final positive is reduced which has a direct bearing on the accutance of the negative and resulting print. The ability to compress or expand contrast by changing the dilution ratio and agitation frequency when extended amounts of time are used to exploit the effect was unheard of till this discovery, all while not sacrificing film speed at all, in fact I've found most films produce proper exposure at box speed.

Remember back to the days of single graded paper, it was always easy to control the bottom and top ends of the print, the difficult part was controlling the micro contrast or contrast between adjacent tonalities to your liking. With the advent of Multi Contrast papers that hurdle became much more user friendly. Now add the flexibility of Reduced Agitiaion Processd film and the creative possibilities are expanded to an even higher degree !

The test was always about the Process rather than the Chemistry.

Cheers.


I understand what you're saying but I think it's unfair to compare semi stand to continuous agitation against each other when different developers are used. I guess I was just assuming that since you had two pieces of film shot identically (1 min apart from each other) that you would use the same developer to compare your results.



"The test was always about the Process rather than the Chemistry."

Since the chemistry AND process were different from each other (different developer + development method) do you consider this an accurate test?

[Wayne]

I understand what you're saying but I think it's unfair to compare semi stand to continuous agitation against each other when different developers are used. I guess I was just assuming that since you had two pieces of film shot identically (1 min apart from each other) that you would use the same developer to compare your results.

I don't understand why the continuous agitation wasn't done in a tank.

[Jim Noel]

Hello Wayne,

The test was designed to show the difference between constant agitation in a tray and Semi - Stand where agitation happens only once at the mid way point. 10 years ago my understanding of Pyro was less than it is now, nevertheless ABC is still considered a highly energized developer as opposite to Pyrocat HD both of which are Pyro based. The Reduced Agitation or Semi - Stand method clearly produced much higher micro contrast even with a considerably less dense negative.

Cheers

They are not based on teh same developing agent. PYRO ABC uses pyrocatechol(pyrogalic acid) while Pyrocat HD uses pyrocatechin plus phenidone or metol.
Catechol and catechin are two very different compounds.

[sanking]

They are not based on teh same developing agent. PYRO ABC uses pyrocatechol(pyrogalic acid) while Pyrocat HD uses pyrocatechin plus phenidone or metol.
Catechol and catechin are two very different compounds.

Correct, and many pyrogallol based developers, like ABC Pyro, need a lot of agitation to avoid uneven staining. Odds are that ABC Pyro would not give acceptable results in stand or stand agitation with very dilute solutions, in fact I would bet that it will not. So given the different nature of the reducing agents it might not be very useful to carry out an apples-to-apples comparison of ABC Pyro and Pyrocat-HD with minimal agitation procedures.

Sandy

[Michael R]

They are not based on teh same developing agent. PYRO ABC uses pyrocatechol(pyrogalic acid) while Pyrocat HD uses pyrocatechin plus phenidone or metol.
Catechol and catechin are two very different compounds.

Just a nomenclature correction - the developing agent in ABC is pyrogallol. The compound in Pyrocat HD is catechol.

One of the reasons why reduced agitation techniques might pose a higher risk of streaking/mottle/uneven stain with pyrogallol developers is that in comparison to catechol, pyrogallol is more strongly ionized (ie more active - and therefore more unstable) at the pH values typical of staining developers. There are other considerations of course, such as the presence of other developing agents, and generalizations can be problematic so the process would likely need to be tested with each individual developer formula. Note also that the emulsion itself can be an important variable in the success/failure of reduced agitation techniques.