This seems like a lot of words that are very delicately trying to sidestep a lack of experience and properly rigorous testing. I can also see your methodology producing a lot of horrible to print negatives, requiring a high grade to set the shadows sensibly, with some painfully tricky dodging - and that's before dealing with getting the highlights where they need to go. Masking should not need to be routine - especially with the sort of thing you propose photographing.
By excessive use of N-, all you are doing is making your life harder than it needs to be. All you want is to straighten out the film curve just enough to get as much of the highlights as needed on a decently linear portion of the curve - knowing that you also need to still be able to print the shadows hard enough that they still look 'right', thus too much underdevelopment is equally to be avoided.
And if you're using an Epson flatbed as a comparator, all you're doing is comparing its sensor noise/ aliasing response. Not much use as an analytical tool. Better to make a few prints in the darkroom and see if by slightly tweaking the overall contrast in printing you can match the results of the differences in negative processing. I can think of many negatives which after persuading on to paper a grade or more harder than 'correct' look dramatically crisper and sharper - all without wasted efforts at the developing stage.
(The only exception is Steve Sherman).
All of this is very helpful, as we run about 750 gallons of D96 in our continuous negative processor and are constantly "chasing the dragon" in fighting bromide build-up, even with what should be adequate replenishment. However we are also constantly being pressured to lower our waste stream, so it is a delicate balance. I am hoping to better understand the mechanisms to assist in this process...
Hi, look, there is no magic in this. If the bromide ion is exceeding the spec values then what "should be adequate replenishment" is pretty clearly not enough. With the possible exception that you have excessive evaporation. The bromide increase in developer (processing tank) is a direct result of development producing metallic silver (from a silver bromide based photo material). To keep it at some spec level you essentially have to dilute it down with replenisher. I'm not experienced with your D96 system, but I can't imagine that it's any different (I've worked mainly in the color neg/printing systems, dating from EP2 paper, which WAS silver-bromide based). If your replenisher formulation contains bromide then you might consider changing the formula, assuming that you have enough analytic facilities to make sure that the processing tank solutions stay within spec. Otherwise, you pretty much have to increase the replenishment rate. With respect to possibly excessive evaporation (relative to replenishment volume) you can check the "specific gravity" of the tank solution; you float a hydrometer (with the appropriate measuring range and precision) in a clear glass cylinder, read it and compare to spec. If evaporation is significant then the specific gravity will go high.
Regarding the pressure to lower your waste stream, I can't imagine that increasing the developer replenishment rate is gonna be a huge factor in this. You're not saying that "they" (I assume your local POTW) are having a problem with bromide ion, are you? (It should be spec'd on your sewer permit, assuming a POTW, if it is.)
as we run about 750 gallons of D96 in our continuous negative processor and are constantly "chasing the dragon" in fighting bromide build-up, even with what should be adequate replenishment
......... If your replenisher formulation contains bromide then you might consider changing the formula, .....
Surely there would be no bromide in a replenisher.
If bromide buildup is a major concern, then maybe a switch to a Phenidone based developer might be worth looking at ? Also allow me the question: if waste created through developer replenishment is such an issue, wouldn't there be much more issue with fixer replenishment?
be much more issue with fixer replenishment?
In particular, Steve sent me scans of a side by side of stand vs regular. I made for him the analytics of the microcontrast of the textures, comparing the tonal range of the textures to the full range of the scene in both situations, negatives were of matching contrast. The histograms I made for him are briefly seen in one of his videos.
I'm pretty sure about two things, first is that the material he sent me was totally fair and had no manipulation, second is that EMA (and other) has a very remarcable impact in microcontrast, if properly done.
In fact everybody can check that, quite easy, just one has to make a regular vs stand side by side, matching contrast, then we scan each negative. In Ps, if we select a crop and later we press Ctrl+M the we see the histogram of the crop, then we see the tonal range dispersion of the crop, if we select a crop of a texture we see the tonal range of the texture. The wider the peak (compared to scene range) the higher the microcontrast, I guess this is easy to understand.
Since I made that analytics (2 years ago) I've been playing with different agitations, and I guess that I learned the effects, before that I was a little skeptical.
It has to be remarked that EMA does not end necessarily in an overcompressed negative, we can develop for normal contrast, what EMA compresses is extreme highlights making its texture printable, a sort of effect we may also obtain with AZO type paper (Lupex, Lodima) , or by using pyro on VC paper, as the strong yellow stain of the highlights selectively prints highlights with a lower contrast grade.
... but what EMA also does, without any kind of doubt, is increasing microcontrast by a very perceptible amount. IMO what Steve says is totally fair. Another thing is if one wants that effect or not, but the effect is there and it's real.
Let's start at the top: rather than getting defensive about your work and firing off PM's,
Full stand development is a bad idea - and there's plenty of evidence of this.
I want to make it clear that the reason I'm questioning your methodology is to ensure that your results have actual worth and aren't more stand-development noise.
Surely there would be no bromide in a replenisher.
What tells if your replenishment rate is right is Br ion concentration, so if Br shifts from specs then replenishment is not adecuate (suposing evaporation is compensated).
I'd try to use a "bromide ion sensor" probe
I'm rather inclined to agree with you. The internet has allowed a lot of hype about stand development and minimal agitation, that's not to say there may not be uses but it's not a coincidence that no well known photographers use these techniques and it seems to be only amateurs experimenting. (The only exception is Steve Sherman).
Ian
Well, not completely. A processor should really live by processed test strips, aka control strips, that are "read" to test for the "correct" level of processing.
I'm curious about these; do you have actual experience with their use in photo processing? We used to occasionally (20 plus years ago) use selective-ion electrodes
they'd likely still end up with Xtol or DDX - especially if avoiding toxic ingredients was a serious concern.
Having Br level in specs is what says if the replenishment rate is the good one. Have you a doubt about that?
Sure, I DO have a doubt. In the perfect world, yes, the bromide ion concentration is an accurate indicator of the correct replenishment rate.
But for a hypothetical problem, let's say that you have a mix error resulting in too high a pH value. And let's say that this gives higher contrast than we were looking for, even with the correct specified bromide concentration. It might be, that to correct the actual processing resulting to the correct aim value, that the bromide concentration has to be slightly raised. Note that I say a mix "error," but it could be a result of slightly off-spec chemicals adding up in one direction.
It occurs to me that we might be looking at different levels of "tightness of control." My background is largely from high-volume pro-level portrait lab work, where we relied on a processing machine staying very consistent from day to day. On the other side of the coin you have (or at least used to) one-hour labs intended for amateur processing. These machines could bounce all over the place, control-wise, and hardly anyone would be able to tell the difference. (My employer, at one time, also owned the largest chain of one-hour labs in the US, so I have some familiarity with this sort of thing.)
Bromide is removed from the replenished tank by the overflow waste it's produced when the replenishment is done, the waste has bromide and the replenisher added not, so equilibrium is reached when the waste (after replenishment) has as much bomide as the "average" film has generated.
What tells if your replenishment rate is right is Br ion concentration, so if Br shifts from specs then replenishment is not adecuate (suposing evaporation is compensated). I recall all that from the times I had serviced some RX medical processors.
"In average" 20% to 40% of the silver in the negatives is developed, well this is an ample range, if negatives are denser more bromide is generated than if negatives are thinner, a roll may generate x4 more bromide than the next one...
On the paper, replenishment can be automaticly adjusted, I'd try to use a "bromide ion sensor" probe (https://www.google.com/search?q=Bro....69i57j69i65.651j0j4&sourceid=chrome&ie=UTF-8 , about $800) to measure bromide, then I'd adjust replenisment rate to lower than normal rate, but when probe says Br is high enough then a control device would activate a Delay-Off timer holding open the replenishment electrovalve (or motor) for an extended period which would double the repenisment dose every time a dose is delivered, until the Br ion is under specs. Of course that project would require an effort for a practical fielding, the single critical matter is accuracy of the Br "Ion-selective electrode" probe in the fielded system, the hacking may be straight for the right technician.
Said simple, a way to automate replenishment dose would be adjusting replenishment to a low dose, and hacking the valve/motor that makes the dose to double that dose if a Br probe says Br is higher than a certain level.
I also prefer Xtol...
Steve Sherman's proposition HD+EMA has two separate benefical effects for printing highlights.
First effect is the mentioned highlight compression from EMA, while making a normal contrast negative that will print mids well in grade 2... extreme highlights reduce its density by perhaps 0.5D from shouldering.
Second effect it's related to stain effect with VC paper, as the extreme highlights have an strong stain it locally shifts contrast to a lower grade, also increasing compression selectively in the highlights.
The two cumulative effects allow to produce this kind of work (below) in a pure optic workflow, without masking, see how there is texture inside the windows, the real print has to be great.
There are picture libraries full of similar images
Thank you; that's very good advice that I wish I could take and implement, but it simply cannot happen with the management, budgetary and safety regulations in place at our facility.
My mind boggles at what it would take to convey just how divorced from good practices and common "lab sense" our work environment has devolved.
If you ever watched "30 Rock" when the Alex Baldwin character quits and takes a government job, you can take that, remove the humor and multiply it by 20 to arrive at the insanity.
We can't change formulas or replenishment rates, all our wash water is trucked-off as hazardous waste, our lab was shut-down for 3 months due to traces of selenium in the water (turned out to be naturally occurring in the well water supply - no it wasn't municipal) and we have to get a "burn permit" to operate a soldering iron.
Get this: my supervisor once asked if we could stop a film processor that was developing 10K feet of dupe negative mid-run to "allow a tour that was late to see the machine in operation". I was sorely tempted to just throw the main power switch and let it fog, but...
Yes, my explorations here are pure fantasy; an escape mechanism to imagine "what if"; what if I were working in a rational work environment where I could make sane adjustments, what would they be?
Humor me.
all our wash water is trucked-off as hazardous waste
That was not my point. The point is, that acceptable bromide levels are much higher in a Phenidone based developer vs. a Metol based one.Phenidone, HQ, metol or Caffenol C all generate exactly the same Bromide, bromide is proportional to the developed silver.
You can get the silver out, no problem, but the bromide stays in there no matter what you do. At some point your fixer will be too slow due to this extra bromide. BTW bromide levels grow at roughly the same pace as silver levels in fixer unless you remove the silver.In general fixer is not usually discarted because it is eahausted, but because silver levels in the liquid are beyond what can be tolerated (around 2gr/L, IIRC) For fixer the solution is a silver recovering device that continously removes silver from the soup, this also was lucrative for a big lab, paying for a share of the chem cost.
That was not my point. The point is, that acceptable bromide levels are much higher in a Phenidone based developer vs. a Metol based one.
You can get the silver out, no problem, but the bromide stays in there no matter what you do. At some point your fixer will be too slow due to this extra bromide.
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