Minimal Agitation Negative versus Tray Processed Negative

[Steve Sherman]

Two 7"x17" negatives identically exposed.
Top negative is Pyro processed for 24 minutes in a tray with continuos agitation pushing highlight density all the way to 1.79 above film base plus fog.
Bottom negative is Pyro processed with a Semi-Stand processing method for a total time of 45 minutes with only one agitation cycle at the halfway point of 1 Minute in length. Highlight density is only 1.33

Conventional wisdom would dictate that a negative of 1.79 would be much more contrasty than a negative of only 1.33 highlight density. Push processing such as the 1.79 negative merely pushes tonalities farther up the "same slope" of the film's straight line. Minimal Agitation forms of film processing actually "increase the slope" of the straight line effectively separating the identical tonalities in the 1.33 negative more abruptly than those tonalities in the 1.79 negative.

Cheers

[chris_4622]

Steve,

The 1.33 negative would print nicely on Azo/Lodima. Is there an advantage using your development method for contact printing on these papers? What differences do you see in the print (contact)?

[Steve Sherman]

Steve,

The 1.33 negative would print nicely on Azo/Lodima. Is there an advantage using your development method for contact printing on these papers? What differences do you see in the print (contact)?

The easiest and shortest way to explain how the Minimally Agitated Neg would be different is the neg would appear to have a grade # 3 Contrast looking print when using grade # 2 Contrast paper. It's a very powerful technique

In response to the suggestion the negs are reversed, they are not, the neg on the bottom shows greater separation while having a lower highlight density

Thanks for commenting

[Willie]

This looks interesting. How is mid tone separation compared to the minimal agitation - in the final prints?

Any downside in negative or image quality that you have found?

[cowanw]

If I am stupid then, I am sure knowing you, you will be gentle.
And if I don't get it then at least 50 other people don't as well.
The highlights (white on positive print and dark on the negative) are clearly darker on the bottom negative. Can you clarify for us who don't know what we are seeing, what's going on?

[Leigh]

In response to the suggestion the negs are reversed, they are not, the neg on the bottom shows greater separation while having a lower highlight density
Is your monitor turned upside down?

The highlight densities of the lower neg are MUCH greater than those of the upper neg on my screen.

- Leigh

[Pere Casals]

Can you clarify for us who don't know what we are seeing, what's going on?

I was not asked, but let me say what I see...

A common photographic process does translate on film light levels to a density scale. For each lux·second exposure level we have a certain density level described by sensitometric curves.

Minimal agitation with diluted developers do more: it enhances microcontrast locally, in special for mids and highlights.

EMA is not only about controlling highlights to prevent excessive density, it also plays with local/selective developer exhaustion. It improves microcontrast because the faster consumption of developer in the white spots of a texture restricts the amount of developer available for the darker spots of the texture, and this increases the local microcontrast without increasing the overall negative contrast.

This can be demonstrated very easily with photoshop, just taking a crop of an EMA negative (of a texturized area) and displaying the histogram. The histogram of the same area is always way wider that the one with a regular development, being both negatives developed to the same general contrast.

Then we have a question: is this good ?

In general this is good, because the image resembles more what a human eye would see in the natural scene, as eye uses an organic reading method that uses locally adaptative contrast evaluation, this is organically performed in several ways, including chemical resources exhaustion. EMA also compensates for flare...

I made personal analisys of EMA shot using local histograms, and personally I've no doubt it works like this, not speaking about a subjective impression, but measuring local dispersion of densities at micro scale compared with overall contrast.


Another question is we want that effect or not, or when we want it...

[faberryman]

The easiest and shortest way to explain how the Minimally Agitated Neg would be different is the neg would appear to have a grade # 3 Contrast looking print when using grade # 2 Contrast paper. It's a very powerful technique
What is the advantage of having a grade 3 print on grade 2 paper?

[Pere Casals]

Is your monitor turned upside down?

The highlight densities of the lower neg are MUCH greater than those of the upper neg on my screen.

- Leigh

Leigh, this is true, scanner had to be in auto mode with different levels, because the mean gray level of both are exactly the same, see it with Ps, F8 Information, and mask regions containing one of the negatives. IMHO the images show the different local contrast, and the 1.33D, and 1.79D have to come from a densitometer. But you are right, the sample images do not tell the truth about max density.

IMHO both negatives should be scanned at the same time (on bed, without the V700 holders) with all auto choices diasabled.



What is the advantage of having a grade 3 print on grade 2 paper?

You obtain a look that otherwise would require CRM+SCIM+"etc" . For sure masking techniques and Alan Ross way selective masking would provide more control.

Well, in fact with A Ross selective masking we have total local contrast control: http://phototechmag.com/selective-masking-part-iii-computer-techniques-for-the-traditional-darkroom/

With EMA we just have higher microcontrast for the same overal contrast. This is good for a sharp look.

[Steve Sherman]

This looks interesting. How is mid tone separation compared to the minimal agitation - in the final prints?

Any downside in negative or image quality that you have found?

Image quality is enhanced to a degree not possible with any other forms of film development, mid tone contrast is exaggerated but because the process is organic there is a smoothness that is present. Downside is only one sheet of film is processed at a time and sometimes it is a 45 minute processing time. Other sheets can be processed in separate tubes to economize on time spent processing fillm

[Steve Sherman]

Yes, the 7x17" negatives are scanned separately and the scan is designed to encompass the given tonalities of each specific negative, no more and no less.
Attached are the two negs side by side on a light tablet I have that is not quite large enough to illuminate both negs at the same time. When the negatives receive the identical amount of back lit illumination it should be clear that the 1.33 neg is in fact less dense than the 1.79 neg.
The important observation is the tonalities of the 1.33 neg show more micro contrast, that is a direct result of Minimal Agitation processing, in this case a Semi-Stand technique was used over a 45 minute processing time. In the more panoramic comparison the negs are turned so that the sky area of each neg abuts one another to offer a clear comparison to the respective densities in each sky area.

Lastly, the 1.79 neg was processed in a tray using ABC Pyro as it was reputed to be a more aggressive film developer than other Pyros back in 2003 when I processed these negs. I was not fully aware of the example that would play out when compared to Semi-Stand processing technique using PyroCat HD developer. I was hopeful that the Semi-Stand PyroCat processed neg. would show more micro contrast than a neg. that was tray processed to a much greater highlight density. Traditional wisdom dictates that higher highlight density will produce a more contrasty negative, clearly that is not the case with Minimal Agitation forms of development.

So, on the chance you align your thinking as some have that the comparison is not valid because two different developers were used, you simply are missing the point of Minimal Agitation and are looking to validate traditional thinking. Further, the technique will work with developers other than PyroCat, just not as well and if you know Pyros like I do you would understand that Pyrogallol based Pyros ( ABC, PMK, Rollo, Wimberleys ) are much more susceptible to aerial oxidation and could not tolerate not being agitated for the length of time that PyroCat can, and it is that length of time without agitation which produces the Adjacency Effects that are clearly present in the 1.33 neg.

If you need further validation, see this LF forum link from a gentleman I had never met who offered this unsolicited critique of these very two negs after attending an Open House I held a few years back. http://www.largeformatphotography.info/forum/showthread.php?129656-Kudos-to-Steve-Sherman!&highlight=open+house

Happy New Year !!

[ic-racer]

Thank you for the additional images!

[Steve Sherman]

Leigh, this is true, scanner had to be in auto mode with different levels, because the mean gray level of both are exactly the same, see it with Ps, F8 Information, and mask regions containing one of the negatives. IMHO the images show the different local contrast, and the 1.33D, and 1.79D have to come from a densitometer. But you are right, the sample images do not tell the truth about max density.

IMHO both negatives should be scanned at the same time (on bed, without the V700 holders) with all auto choices diasabled.




You obtain a look that otherwise would require CRM+SCIM+"etc" . For sure masking techniques and Alan Ross way selective masking would provide more control.

Well, in fact with A Ross selective masking we have total local contrast control: http://phototechmag.com/selective-masking-part-iii-computer-techniques-for-the-traditional-darkroom/

With EMA we just have higher microcontrast for the same overal contrast. This is good for a sharp look.

I had to think about wether to take on this question given the named photographer and masking technique you eluded too.

However to be fair to my technique there are some inconsistencies with some general statements about the EMA technique, especially the closing statement.

My knowledge of masking is limited especially since I perfected the EMA technique I abandoned any pursuit of unsharp masking.

In reality the EMA technique provides significant flexibility in the amount of Micro Contrast in the final Silver print. When you design negatives in the style I do, very low highlight density requires a reduced amount of soft contrast light to effect detail in the final silver print, that in turn allows more hard contrast light which produces higher Micro Contrast, most clearly seen in the Mid Tone region. If for whatever reason Mid Tone Contrast is too high you would simply increase the length of the soft Contrast exposure and reduce the hard Contrast exposure time which directly reduces Mid Tone contrast, it's a simple cause and effect.

Lastly, the EMA technique is completely organic and therefore provides a smoothness yet vibrant transition of tonalities, particularly in the Mid Tone region, the area of any print that most respond to the most. To be clear, the amount of Adjacency Effects that different film formats and degree of enlargement of the Silver Gelatin print will govern the type of Minimal Agitation technique used.

[peter schrager]

Steve how much developing time are we talking for your process..??
thanks, Peter

[Steve Sherman]

Steve how much developing time are we talking for your process..??
thanks, Peter

Depending on contrast range of the original scene the total time could range from 15 - 75 minutes with greatly reduced Agitation time.

SS

[Pere Casals]

there are some inconsistencies with some general statements about the EMA technique .


Perhaps problem is the thought that a sensitometric calibration explains all. It is true that sensitometry explains very well how a regular photographic process works, but with Pyro + EMA we are talking about compensation, and IMHO this is more complex, as (with EMA) response is also dependant on local exhaustion of developer and also on local bromide concentration that also influence local development. I mention the concepts I think I understand, but more can be there...

I was thinking that perhaps Pyro has an advantage for EMA, as density is partially built with stain then less bromide is generated for building the same density, with less risk of bromide streaks... just a thought. Also Xtol, for example (IIRC) is less prone to restrain development from byproducts... Perhaps that delicate equilibrium is needed to obtain a sound result....

[John Layton]

Steve...any comments about how EMA might (or would) work with brush development? The reason I ask is based on my current setup - with six 5x7 developer trays enclosed in a single 20x24 tray (other solutions batched in single trays). My developer agitation routine has involved tilting the 20x24 tray around...which works great except I will sometimes get some "micro scratches" on a film's base as it moves about its tray - so my next move is to either very gently lift and flip each negative in succession...or go to brush agitation, either of which would offer the further advantage of tailoring agitation to each negative.

As my routine involves doing six single developer trays at once...you can see what compels me to adapt this to EMA. And I've examined a few of your negatives up close (with a loupe) when I last visited...and yes indeed - they show a nice balance of smoothness/sharpness with wonderful micro contrasts, with resultant prints likewise...and exhibiting no hints of "over manipulation." So I am feeling very motivated!

[Pere Casals]

I will sometimes get some "micro scratches" on a film's base as it moves about its tray

Tap water contains variable amounts of sand and metal particles. You can filter it out or use deionized/distilled water for mixing the developer, and also filtering it again after mixing if it is the case of a powder developer.

[John Layton]

Hmmm...I do utilize a pair of 5 micron filters - but the elements are now overdue for replacement. Could help.

[Pere Casals]

Hmmm...I do utilize a pair of 5 micron filters - but the elements are now overdue for replacement. Could help.

Another way I used is to place some vertical sticks in the tray (with hot glue) in order the sheet cannot move, as it is retained by the sticks when rising a side to agitate.

[esearing]

Steve,
It may be more helpful to show the density for the same four points on each image . Base/fog density, Highlight densitity -BF, shadow densitity-BF, and a midpoint-BF.
This might show that there is only slightly more/less separation between the points.
If not, what does that tell us about overall density and its effect on midtone contrast? Is having the thinner compressed negative enough to allow you to expand contrast more while printing, than is a thicker negative which may have more contrast already built in.

[Jac@stafford.net]

Another way I used is to place some vertical sticks in the tray (with hot glue) in order the sheet cannot move, as it is retained by the sticks when rising a side to agitate.

Great idea, and perhaps add two horizontal rods to minimize vertical movement?

My old favorite was Honeywell Nikor Rocking Print Trays, for large film. It's worth a Google search. Excellent for maintaining temp and for minimal (if you wish) chemistry.

Heath made one with a more severe curve, perhaps to minimize sink space.

173274

[Pere Casals]

With vertical sticks it worked perfect... but I agitate gently...

[John Layton]

Yup...the old "canoe" tray - great memories! Also great for saving chemicals...but not so great for EMA!

[Jac@stafford.net]

With vertical sticks it worked perfect... but I agitate gently...

I understand, and on second thought cross-bar sticks might introduce new turbulence. Thanks for the correction.
.

[Steve Sherman]

Perhaps problem is the thought that a sensitometric calibration explains all. It is true that sensitometry explains very well how a regular photographic process works, but with Pyro + EMA we are talking about compensation, and IMHO this is more complex, as (with EMA) response is also dependant on local exhaustion of developer and also on local bromide concentration that also influence local development. I mention the concepts I think I understand, but more can be there...

I was thinking that perhaps Pyro has an advantage for EMA, as density is partially built with stain then less bromide is generated for building the same density, with less risk of bromide streaks... just a thought. Also Xtol, for example (IIRC) is less prone to restrain development from byproducts... Perhaps that delicate equilibrium is needed to obtain a sound result....

Yes there is a very delicate equilibrium which must be maintained between strength of developer, frequency of agitation and length of agitation to actually produced Adjacency Effects. The Pyro stain is important to a degree but not as important as Pyro developers in general are "tanning" developers and therefore harden the film's emulsion within the first few minutes in solution. That is the main reason why long periods of development time can be tolerated where as with non Pyro developers there are a number of short comings when the film remains in chemistry for extended periods of time. Think of the EMA technique in this way, Dilution allows Time to be extended, Time allows Infrequent Agitation when these three components in processing are in delicate balance, only then will the developer exhaust, and only then will Adjacency Effects happen. Very simple, to increase Adjacency Effects increase the amount of time the developer has exhausted before a new agitation cycle begins.

Compensation or compression of highlight densities is much more about dilute developer than a trait exclusive to Pyro Chemistry.

Hope this helps clear things up.

[Jac@stafford.net]

[...]not as important as Pyro developers in general are "tanning" developers and therefore harden the film's emulsion within the first few minutes in solution. [...]

Harden. I'm not sure what it means. Does it apply to the whole emulsion, or does it vary with density caused by greater exposure? Thanks for any insight.

[Steve Sherman]

Steve...any comments about how EMA might (or would) work with brush development? The reason I ask is based on my current setup - with six 5x7 developer trays enclosed in a single 20x24 tray (other solutions batched in single trays). My developer agitation routine has involved tilting the 20x24 tray around...which works great except I will sometimes get some "micro scratches" on a film's base as it moves about its tray - so my next move is to either very gently lift and flip each negative in succession...or go to brush agitation, either of which would offer the further advantage of tailoring agitation to each negative.

As my routine involves doing six single developer trays at once...you can see what compels me to adapt this to EMA. And I've examined a few of your negatives up close (with a loupe) when I last visited...and yes indeed - they show a nice balance of smoothness/sharpness with wonderful micro contrasts, with resultant prints likewise...and exhibiting no hints of "over manipulation." So I am feeling very motivated!

Hello again John, you are one of the few active members on this LF forum that has actually seen my negatives and can speak to the differences you've seen, and of course the resulting prints.

So, I believe your 6 individual trays in one 20x24 tray is for the purpose of developing multiple sheets at one time to economize on time processing film, that seems to be a constant with those who pursue the EMA technique. First, the micro scratches you speak of could be happening the film holder just as easily as the tray, I get micro scratches now and then but as long as they are on the base side they really don't show up in the printing stage.

Here's how I see the Plus and Minuses of the Tray versus EMA Tubes.

Tray Pluses, 6 sheets in a 30-40 window, brush development would work with a Pyro chemistry as has been explained earlier, Pyro developers in general "tan" the emulsion or harden the emulsion very early on in the processing time, first 2-3 minutes ( no hardening fixer required, it's a waste of money, and the ammonium present in a hardening fixer will serve to make the film's emulsion more brittle over time) However, I see brush development of 6 separate sheets of film as more inconsistent than a rotary action.

Tray Minuses, 1 ) Greater aerial oxidation and not as easy to replicate from one session to the next, i.e. darkroom humidity and ambient temperature must be more consistent than a closed tube. 2 ) separate trays in 20x24 tray, process must be done in total darkness 3 ) there is a decent chance that one or more sheets will float to the surface of the developer and become mottled from lack of complete coverage, remember total darkness 4 ) With approx. 35 sq. in of open surface of developer exposed to oxidation Pyrogallol based developers such as PMK, ABC, Rollo, Wimberelys are OUT, developer would oxidizes in seconds. Even, PyroCatechin developers such as PyroCat would be more susceptible to rapid oxidation.

EMA Tube Pluses 1 ) tightly controlled oxidation rate as there is virtually no air space between the tube and cap. 2 ) Agitation is done in a rotary manner much the same as Jobo and possibly more consistent than rocking 3 ) When processing with up to three separate tubes, the film goes in approx. 4 minutes apart, and therefore comes out with only one sheet in fixer tray with less chance of scratching, again in darkness for the first 90 secs.

EMA Tube Minuses 1 ) The most I can processes in a 40 minute window is 3 sheets, the new Tube design has cured all other short comings of my previous method IMHO.

Joh, I'm likely bias when it comes to the Tube method, but at the same time this is the ONLY way I have processed my film for the past 14 + years and have continued to tweak the formula that was successful back in late 2003. Thanks for commenting and continued success with your EMA workflow.

[Steve Sherman]

Steve,
It may be more helpful to show the density for the same four points on each image . Base/fog density, Highlight densitity -BF, shadow densitity-BF, and a midpoint-BF.
This might show that there is only slightly more/less separation between the points.
If not, what does that tell us about overall density and its effect on midtone contrast? Is having the thinner compressed negative enough to allow you to expand contrast more while printing, than is a thicker negative which may have more contrast already built in.

This is the age old argument that building contrast into the negative is the way to create greater Mid Tone Contrast. While that thinking still has a strong hold today, it should have gone by the wayside the minute THICK EMULSION FILMS no longer existed. Only when emulsions have a significant thickness to them did that thinking bear fruit. Not to mention the Silver rich papers that were available in those days when hand in hand with those thick emulsion films.

Today's thin emulsion films respond wonderfully to Pyro base developers due to the tanning effect, look at a conventional negative in "glancing light" and you'll see a smooth uniformity of surface across the entire sheet of film. Hold a Pyro processed negative up to glancing light and you'll see an ecthing or layering effect across the varying densities across the surface of the film. One reason acutance is palpable with Pyro developers, and that effect is heighten when using and EMA form of film development.

With all due respect, the real numbers than mean something to me is the Eye Test, and when I look at prints that I make today from negatives I exposed and processed 20 years ago with the best option of the day back then, Tri-X and HC 110 developer the difference is not slight, it is striking. The Mid Tone separation is greater, but what jumps out is how harsh the 20 year old negs look when compared to the way I design negatives for EMA processing with PyroCat HD.

Lastly, I no longer build contrast into the negative, thats' one reason why my highlight densities are so low. I like to say I build Tonality into the negative and then build Contrast in the printing process.

Thanks for commenting Eric !

Cheers, SS

[Steve Sherman]

Harden. I'm not sure what it means. Does it apply to the whole emulsion, or does it vary with density caused by greater exposure? Thanks for any insight.

That's a very good question, I can't say for absolute but my gut tells me the hardening process comes to completion at some point. I believe it may take longer with an EMA type of development but in end, say 5 minutes rather than 2 minutes the entire emulsion will be uniformly hardened.

Thanks for reaching out

[minh0204]

Pardon my jargon illiteracy, but what does EMA stand for? Extremely Minimal Agitation?

[Alan9940]

Pardon my jargon illiteracy, but what does EMA stand for? Extremely Minimal Agitation?

Very close... Extreme Minimal Agitation

[bob carnie]

That's a very good question, I can't say for absolute but my gut tells me the hardening process comes to completion at some point. I believe it may take longer with an EMA type of development but in end, say 5 minutes rather than 2 minutes the entire emulsion will be uniformly hardened.

Thanks for reaching out

From my understanding, as the silver blooms out with development, the tannin effect hardens around the silver and stops blooming, therefore allowing the highlights to set first, mid-tones second and shadow last. Gordon Hutchings book on Pyro explains this well and IMO it is the most powerful advantage of pyro based developers.

[Steve Sherman]

From my understanding, as the silver blooms out with development, the tannin effect hardens around the silver and stops blooming, therefore allowing the highlights to set first, mid-tones second and shadow last. Gordon Hutchings book on Pyro explains this well and IMO it is the most powerful advantage of pyro based developers.

A very good explanation and I would agree the tanning effects of Pyro developers are a major player in the acutance seen in Pyro processed negs. It should also be noted there are two main Pyro developing agents, Pyrogallol Acid, which many popular Pyro formulas used such as PMK Pyro, Rollo Pyro, ABC Pyro, WD2D are the most common. PyroCat HD is formulated from Pyrocatechin or Catechol. The Pyrocatechin developing agent when compared with Pyrogallol operates in a higher pH and therefore is more stable, does not oxidizes as quickly and provides a finer grain structure, especially important to roll film and small sheet film users. Pyrogallol based Pyros do not preform nearly as well as PyroCat HD when using the EMA technique to process most any film

[sanking]

From my understanding, as the silver blooms out with development, the tannin effect hardens around the silver and stops blooming, therefore allowing the highlights to set first, mid-tones second and shadow last. Gordon Hutchings book on Pyro explains this well and IMO it is the most powerful advantage of pyro based developers.

I agree with Bob in that the most powerful advantage of pyro type staining and tanning developers is the hardening, not the stain. From an article I wrote a long time ago.

"Highlight separation, sharpness and acutance are increased because Pyro gives more pronounced edge effects than other developers. This is due to the fact that there is very little migration of silver halide during development, resulting in a more precise reduction, which enhances sharpness, and because Pyro tans and hardens the gelatin during development, thereby reducing the effects of irradiation (scattering of light in the film emulsion) and infectious development (spreading of silver development beyond the exact image boundaries)."

The use of a Pyro type developer with EMA development does not, of course, preclude other types of post-development controls, including various forms of masking. Or for that matter, scanning and digital post-processing.

Sandy

[bob carnie]

Steve pointed out earlier in one of his posts about the fact if you look at a pyro negative from an angle you can actually see the relieve surrounding areas in the image, I have never seen this with any other developer than pyro , but I do see this in my negatives when I have used pyro.