ISO Mistake, how to correct in development ? profesional advised needed.

henry finley · Jan 22, 2013

Michael R 1974 said:
It's off topic I guess, but I've done a lot of testing on Microdol and Perceptol at various dilutions with various agitation routines. When the curves are plotted, even at 1+3 compensating action is minimal. As for speed, my advice to anyone wanting to fully exploit the image characteristics of these D-23-based extra fine grain developers has always been the same, which is to determine your working EI at stock strength, and use that same EI for 1+1 and 1+3 (ie accept the speed loss regardless of dilution). I've found graininess increases very quickly if you try to get more speed - even at 1+3, and it doesn't take much until you are gaining nothing grain-wise versus D-76, XTOL, and other developers that will give you better speed. This behaviour is consistent with a developer that is not truly compensating, and is weakly alkaline.

The other point is that I still wouldn't consider OP's Tri-X "badly" overexposed. We're talking 2 stops over ISO, probably closer to 1 stop over the working EIs people often use. And since this was a low contrast scene, there is plenty of room on the curve to accomodate the luminance range. OP could use Perceptol, but I don't think there is anything to be gained in this particular situation vs D-76. As for pulling, that will decrease local contrast in an already low contrast scene. A compensating developer would also flatten local contrast.

Well, Michael 1974, since you've obviously done your homework, do you think Perceptol REALLY IS a Microdol clone? That's what I've heard, but after I lost Microdol from this world, I never tried Perceptol. Is it really the same thing, or is it the same thing like Post Toasties is the same thing as Kelloggs Corn Flakes (which is NOT the same). I'll take your word on this, because I want my Microdol back. This D-76 bit just isn't cutting it for me. Camera stores are NOT camera stores--they're computerized junk stores, and don't have anything on the shelves any more. The computer and the economy has fouled everything up.

henry finley · Jan 23, 2013

Michael R 1974;1451231 PE knows what it was but he won't disclose it. Perhaps Perceptol contains something like it said:
Thanks. I appreciate. I wonder who PE is though. Further, you would think that since Kodak has abandoned the manufacture of it that they would let loose of the true formula to the public. Doesn't make sense for a company now bankrupt and practically out of business to still keep secrets. When I die, I'll be more than happy to let loose of my money and posessions. I'll try this Perceptol. Untill Apple Computer invents a time machine so I can buy one and go back to the 70's and stay there.

c6h6o3 · Jan 26, 2013

I have to agree with Ralph Lamabrecht and Michael R 1974. Change nothing in film development and then print them well.

I make your "mistake" all the time, since I rate my 400 speed film at 200 and place the shadows on Zone IV. Ansel Adams would therefore say that I'm shooting it at 100. Indeed, when I take incident meter readings that's the ISO I use.

All the photographs on this Tumblr blog page were exposed in this manner. The first one contains only 2 zones of contrast, the last one about 12 zones. So in the final analysis not even the tonal range makes that much difference when it comes to exposure.

There are only two ways to make a two stop exposure mistake. You picked the right one.

RalphLambrecht · Feb 12, 2013

welcometo APUG;i'm glad to see that the florida crowd is growing. as to your issue, dev normallyand use the highest contrst filtration you can get out of your darkroom. good luck

pentaxuser · Feb 12, 2013

So OP what happened when you went with the consensus. It is always nice to know how successful the advice was

pentaxuser

RalphLambrecht · Feb 14, 2013

i agree, feed back is nice and valuable!

ISO Mistake, how to correct in development ? profesional advised needed.

henry finley

henry finley

c6h6o3

RalphLambrecht

pentaxuser

RalphLambrecht

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