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

[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]

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-ma...onal-darkroom/

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

[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.in...ght=open+house

Happy New Year !!

[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-ma...onal-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.

[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....

[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.