Why longer dev times APPEAR to be required for new D76 - follow the saga (hint, new D76 is fine)

[AZD]

I guess this is as much a comment as a question, but it has me stumped. Has anyone noticed a change in development times using newer packages of Kodak D76? I have suddenly experienced this with two new 1-gallon powder bags and can't find any other variable to explain it.

MODERATOR's NOTE ADDED - see the OP's resolution of this in his post #18 on July 14, 2021)
Some background - I've been using D76 since getting back into film about 2 years ago. It has been good and consistent, and I was finally getting predictable negatives that fit my paper (Foma Variant 111 in LPD). I always process at 20C, always with the same thermometer and a water jacket for temperature control. Same brand of distilled water for chemistry, same agitation, same bulk roll of Ultrafine Extreme 100. Cameras are all within 1/2 stop on the meters with the same lens... basically I have been as consistent as possible while using a spare bathroom.

To my disappointment, a new package of D76 resulted in flat, under developed negatives on two rolls taken with two different cameras. Shadow detail is all there, but overall contrast is much lower than desired. I though perhaps it was the jug (which for unknown reasons had developed a sort of weird plastic smell) and tossed the gallon. Another new bag of D76 with a new jug has also resulted in flat negatives during some initial tests. It seems like I need to add maybe 30% to my times to get back where I had been. This is rather unfortunate since the last gallon (not including the dumped one) gave me some of the best negatives I've ever had.

So, I'm either missing something fundamental, or there has been a change. The two recent bags are both post-recall, made in the USA for Sino Promise. Perhaps getting a bit less objective, to my nose they didn't smell quite as expected, not as strong, almost odorless. Nor did they have the slightly pink color I've seen before when first mixing in the clear 1-gallon distilled water jugs. I don't know what that means, if anything at all.

Has anyone else experienced this? Any ideas about what else could have changed?

 

[Bill Burk]

I have been having longer development time with D-76 1:1 but am studying the possible reasons. It’s not the new stuff.

If you don’t now do sensitometry, it’s a good way to quantify the results you are getting in a meaningful way.

One change I made is that I used to have a reverse osmosis filter and now I use store-bought water in plastic jugs to mix.

 

[Nicholas Lindan]

The best solution may be to mix up D-76 from the raw chemicals. And, as Bill has mentioned, using distilled water for developer is a very good idea if consistent results are your goal.

 

[AZD]

Yes, I'm big on consistency these days. I've been down the path of multiple unknown variables all at once. It always leads to disappointment. Distilled water and controlled temps are what I practice these days.

My latest results from D76 really do have me considering raw chemicals, or completely switching to something else. I don't want to dial in my times with every new batch. That was the whole point of using a well known standard developer that can be found anywhere. No alchemy, sorcery, or magic potions required.

Bill, interesting about your longer times. While I at least believe there is something related to the newer D76 packs, even before that I had to develop for longer than most datasheets suggest for 1+1. That was partly expected as my old (but very capable) Federal 219 enlarger uses a plate of opal glass as the diffusor. It really likes a negative with higher than "normal" contrast. "Sparkly" negatives, if that makes sense. I don't have a densitometer, but my eye, empirical it may be, is pretty adept at knowing what'll work well - clearly visible shadow detail and highlights that many would probably consider too dense. Such negatives print beautifully with ease on my old tin can enlarger from Brooklyn.

As a sanity check, this evening I processed two identically exposed test strips of UFX100 in two other developers: Compard R09 1+50 for 12 minutes, and Ethol LPD 1+10 for 10 minutes. These are times I have worked out over the past few months, and both gave me the sort of negatives I know will work. Just wondering how D76 went sideways after working so well. Honestly it could be something I'm doing wrong but not aware of, but it's only happening with D76.

BTW, using LPD isn't really a fair comparison as it's almost impossible to get a flat negative. At 1+10 it is still a very active developer that gets to work on the highlights right away. Combined with UFX100's tendency to halo a bit, the end result can be a bit too glowy if overdone. It has the potential to work well for subjects were a sense of bright light is desired, which I often do. Still dialing it in. I originally tried LPD just to see what would happen and ended up liking it enough to fine tune. I wouldn't use it all the time though.

 

[pentaxuser]

So in summary, I think, your conclusion is that the "new" D76 needs 30% more development time than the old or is this a prediction of what it will require based on your current disappointing results using the "old" D76 times or is this your old times?

I can't explain it but it seems incredible that KA/SinoPromise has now made a developer that it chooses to call by the same name and either does not realise it requires an extra 30% or just as bad or maybe worse, has chosen not to announce that the new packs of D76 requires a very substantial change in times

Out of the many D76 users here, has anybody else seen this effect? If you have, do us all a favour and let us know. That's what a photography forum is for, isn't it?


pentaxuser

 

[gone]

Try the D76 clones, maybe they're OK. I had to stop using D76 (still occasionally buy an OLD package of it) because Kodak....well, I haven't got a good word to say about that company and the incompetent snakes that run it. Getting burned on 2 packages of D76 that looked like root beer or molasses put me off, along w/ a Kodak rep lying to me about replacing them. Don't support companies like this, thy're not at all the only game in town.

 

[MattKing]

Have you communicated your concerns to the manufacturer?
kodakpaperchem@pro.sinopromise.com

 

[Bill Burk]

So in summary, I think, your conclusion is that the "new" D76 needs 30% more development time than the old.

I think that’s a good summary, AZD found underdeveloped negatives while being careful to control the main factors that affect development.

This can happen to anyone, for any reason. D-76 can be off by 30% and you’re still going to get usable negatives, which is why I love it.

Now whether or not the new stuff is different? That’s what this thread is about.

Here is a thread telling of my troubles, where I got 30% less development, but with vintage, aged D-76. I have data to compile which may illustrate what went wrong. https://www.photrio.com/forum/threads/recant-d-76-does-not-last-forever.184393/

The next thread asks a question for which this thread is the answer… https://www.photrio.com/forum/threads/why-use-step-wedges-densitometers-etc.184259/

 

[AZD]

I have used ID-11 before with good results, and I think that may give me an answer. Fortunately I kept notes on times and which rolls of film were processed, so there is at least something to compare with. It's not available locally so I'll have to order a package the next time I order online. ID-11 vs. D76 would be the best comparison.

I too would be very surprised if D76 had changed that much, so it would definitely be helpful to know if anyone else has experienced something similar. If not, the finger points at me. Chances are it's user error, but it's something isolated to my use of D76, and only with the newest packages. Strange coincidences are possible, and it wouldn't be the first time something "unrelated" is the real culprit. Short of isolating and correcting the exact cause, the only sensible solution is to find something else that works as expected.

Besides wondering what happened, my real issue is half a dozen undeveloped rolls of film with images I can't recreate - ever. So it is imperative, at least in the short term, to find something that removes chance from the equation. Work to do...

 

[Adrian Bacon]

If it helps, I just used some of the new D-76 1+1 (in the new, new packaging that is the same as the old packaging) on a roll of Pancro 400 and it seemed fine. It was customer film, so I have no way to be objective about it, but I followed Berggers data sheet for it and the roll out of the tank looked reasonably normal to me.

 

[Don_ih]

Arista 76 seems to be pretty much identical to Kodak d76. ID11 is perhaps a bit better than d76, since it's in separate packets and therefore doesn't need whatever magic Kodak used to keep the chemicals from reacting. But if you get raw chemicals, you can routinely mix up the amount you will use before it goes bad (a litre or a gallon or a barrel) and the dry chemicals keep forever (if kept dry). Low contrast in d76 sounds to me like hydroquinone is bad (or missing). It would become weak d23.

 

[Bill Burk]

The next thread tells of densitometer alternatives.

https://www.photrio.com/forum/threads/film-densitometer-alternative.184190/page-2#post-2425614

 

[Bill Burk]

@AZD
Here is a quick plan.

Using a fairly reliable shutter speed (you can use a phone based shutter timer to check times over a fifteenth second or so) take a series of pictures.

Based on the idea that a contrast of about 0.5 is a good development aim…

Take three shots of a blank unfocused flat shape (gray card). Two at a small f/stop like f/8 (these will be your thin negs), and then open up two stops and take another (this will be denser than the other two).

If the two thinner negatives on top of each other look about the same as the third shot, then you are getting close to 0.5 contrast, and that development time is good (or a bit longer since 0.62 is kind of the ASA test standard contrast).

 

[AZD]

Thanks for the tip! Short of having a densitometer I think that's the best test currently available to me. I'm going to give it a try.

Just to make it more interesting, I have a photo resistor and accurate digital meter. It ought to be pretty easy to at least quantify whether the stacked negatives are similar (or not) to the single, more dense negative. Even without calibrating anything, with fixed light output and rigid mechanical orientation, I should be aiming for the same resistance, whatever it happens to be. At least I think that's correct anyhow. TBD.

 

[Bill Burk]

Sounds good. I want to add, the denser negative should be stacked with a “clear” negative - so fire off a shot with the lens cap on (total 4 shots).

35mm film often has a gray base so you need two for a proper comparison.

 

[AZD]

Yes, makes sense, the extra layer of film base + fog to control for doubling the thinner negs. Got it. Thanks again.

I have a package of ID-11 on the way.

 

[AZD]

It's been a busy month with little time for experimentation. But, I think I finally found what I was missing...

I made two separate test strips as close as possible:
- Ultrafine Extreme 100 from the same bulk roll
- Tripod mounted Pentax Spotmatic SP w/ Takumar 50 f/1.4 SMC (a combination I have used reliably, though admittedly all mechanical with possible inconsistencies)
- De-focused on an even surface (the back cover of Fabio Ponzio's East of Nowhere, a great collection of photos BTW)
- Even, almost soft box lighting from the smoky sky, plus even shade provided by a big tree
- 1/60 second at f/11 once, and f/5.6 twice, plus a blank, plus a bonus shot of the shed just because

Each roll was developed for 12 minutes at 20 degrees using "Ilford agitation". One in ID-11 1+1, and the other in D76 1+1.

And the results were.... almost identical. The ID-11 was a little more dense, but close enough I wouldn't care which had been used.

So, the only real possibility left is that my old D76 was... old. After looking into it, I believe it may have become more active over time, and I just happened to like the result. I can't prove it. but it makes sense because everything changed after it was gone.

Thanks to everyone for their help and suggestions. This has been a very informative experiment, and fortunately there are some real conclusions:
- Kodak is doing a fine job with their D76
- D76 and ID-11 are pretty close
- I need to use my gallon of D76 faster, or mix smaller batches from quart/liter packages or raw chemicals, or possibly switch to something like HC-110 for on-demand use.
- I need to stop using my remaining UFX100 for test strips and make actual pictures now

By the way, @Bill Burk, the two stacked f/11's were more dense than the f/5.6 + blank. Estimating maybe a stop (?) purely by eyeball. Haven't had a chance to dive into that yet, but it's the opposite of what you'd anticipated. So, barring any camera/lens/meter problems, I'm not sure what I just proved on that point, except that my understanding of sensitometry is quite limited. The f/11 at 1/60 was an average reading from the Spotmatic meter. The f/5.6 frames are less dense than the exposed film leaders, so presumably I didn't accidentally overexpose and place these frames on the shoulder of the film curve. Any advice sorting that out would be appreciated. I'm going to have to find my old copy of The Negative.

 

[Bill Burk]

By the way, @Bill Burk, the two stacked f/11's were more dense than the f/5.6 + blank. Estimating maybe a stop (?) purely by eyeball. Haven't had a chance to dive into that yet, but it's the opposite of what you'd anticipated. So, barring any camera/lens/meter problems, I'm not sure what I just proved on that point, except that my understanding of sensitometry is quite limited. The f/11 at 1/60 was an average reading from the Spotmatic meter. The f/5.6 frames are less dense than the exposed film leaders, so presumably I didn't accidentally overexpose and place these frames on the shoulder of the film curve. Any advice sorting that out would be appreciated. I'm going to have to find my old copy of The Negative.

No worries, means that you have less than 0.5 contrast between the average reading and a couple stops greater exposure. It may mean that you could develop longer if you wish next time. But it’s not a critical breakdown in theory or testing, just a suggestion that you have headroom above

 

[BradS]

@AZD
Here is a quick plan.

Using a fairly reliable shutter speed (you can use a phone based shutter timer to check times over a fifteenth second or so) take a series of pictures.

Based on the idea that a contrast of about 0.5 is a good development aim…

Take three shots of a blank unfocused flat shape (gray card). Two at a small f/stop like f/8 (these will be your thin negs), and then open up two stops and take another (this will be denser than the other two).

If the two thinner negatives on top of each other look about the same as the third shot, then you are getting close to 0.5 contrast, and that development time is good (or a bit longer since 0.62 is kind of the ASA test standard contrast).

Wow! brilliant yet simple and easy to understand. Thanks!

 

[AZD]

Thanks, @Bill Burk! I think your suggestion agrees with the conclusions I had come to, regardless of any particular theory. It's nice when things line up like that.

July was quite a busy month so I didn't get much chance to experiment further with D76 vs ID-11. In late June I had developed a pretty important (to me anyway) roll of Ultrafine 100 with Rodinal because I needed a print asap and just went with what was working. The sharpness and detail were excellent, and the convenience such that that I used Rodinal for everything I had left. Yeah, straying from my "keep it consistent" approach. Still, I'll be returning to D76 soon and at least feel like I can analyze the results a bit better going forward. Thanks again!

 

[MattKing]

As the issue has been resolved, I have updated the thread title and added a reference to the resolution in the OP's opening post.

 

[Bill Burk]

@AZD
Here is a quick plan.

Using a fairly reliable shutter speed (you can use a phone based shutter timer to check times over a fifteenth second or so) take a series of pictures.

Based on the idea that a contrast of about 0.5 is a good development aim…

Take three shots of a blank unfocused flat shape (gray card). Two at a small f/stop like f/8 (these will be your thin negs), and then open up two stops and take another (this will be denser than the other two).

If the two thinner negatives on top of each other look about the same as the third shot, then you are getting close to 0.5 contrast, and that development time is good (or a bit longer since 0.62 is kind of the ASA test standard contrast).

This specifically was a mistake. I had it wrong. The two normal shots superimposed do not add density together to equal the overexposed shot.

The normal shot is expected to differ in density from the overexposed shot by one stop.

You can use an 0.30 ND filter to compare.

Or you can check that print time is doubled.

But you can’t stack two thinner negatives to expect a match to the denser negative.

 

[AZD]

Hmm, I tried this a few times as suggested and never got it to work out quite as described… No matter, I eventually got my contrast under control. These days replenished XTOL is my developer of choice and is pretty consistent.

FWIW, I found this recently but haven’t yet tried it:

Personalizing Your Film Speed, Part 1

Personalizing Your Film Speed, Part 2

It’s an empirical way to dial in EI and development. Very clever.

 

[Bill Burk]

Haa, it never would have worked.

I haven't created a simplified film speed test, so if you like that advice it's as good as any.

Here's my new thread about two-stops test and 0.30 ND filter, though dcy says he might try four-stops and an 0.60 ND filter which I think would work as well.

Confirming Film Development Time using an 0.30 Neutral Density Filter

I added a resource to describe a simple film test that can be done using an 0.30 neutral density filter. Here is a link to the article: Confirming_Development_Time The way it works is that normal development is pretty close to a 50% gradient, and so if you bracket a couple shots. Give one...

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