My D-76 (Stock dilution) won't die

[Kirks518]

In October of 2014, I mixed up a bag of D-76 that had a use by date of 2008. I split it into three 1/2 gallon bottles, each of them about 2/3 full. These are the brown 'Delta Datatainer' bottles. I keep them on a shelf in a spare bedroom, where ambient temps range from 72°F to 82°F. I have developed approximately 40 rolls of 120, 15 rolls of 35mm, and about 10 sheets of 4x5 in the stock dilution. I then pour it back into whatever container it came out of, and use it again next time.

A couple of times I've increased the developing time by anywhere from 15 to 45 seconds, thinking the developer is getting depleted and the additional time would be needed. But every time I do that, the negatives are too dense for my liking.

So why is my D-76 holding up for so long? Kodak says stock solution is good for about 6 months and/or 16 rolls, but I've nearly tripled the time, and more than tripled the yield. Is Kodak that conservative in their estimates, or is what I am getting typical of D-76?

 

[Xmas]

In October of 2014, I mixed up a bag of D-76 that had a use by date of 2008. I split it into three 1/2 gallon bottles, each of them about 2/3 full. These are the brown 'Delta Datatainer' bottles. I keep them on a shelf in a spare bedroom, where ambient temps range from 72°F to 82°F. I have developed approximately 40 rolls of 120, 15 rolls of 35mm, and about 10 sheets of 4x5 in the stock dilution. I then pour it back into whatever container it came out of, and use it again next time.

A couple of times I've increased the developing time by anywhere from 15 to 45 seconds, thinking the developer is getting depleted and the additional time would be needed. But every time I do that, the negatives are too dense for my liking.

So why is my D-76 holding up for so long? Kodak says stock solution is good for about 6 months and/or 16 rolls, but I've nearly tripled the time, and more than tripled the yield. Is Kodak that conservative in their estimates, or is what I am getting typical of D-76?

Kodak are conservative.
You are being careful with storage but if you put too many films through then the contrast may go up so you may be on thin ice, ie I get more contrast going past Ilfords recommendations, by accident...

 

[DREW WILEY]

Kinda like waving a red coat in front of a bull... there will come a point ...

 

[Kirks518]

DRew, that's what I figure, so I add some time to offset, but each time I do that, the negs looked over developed. I would have thought that by now I'd see some indication of exhaustion, but using normal times, the negs are coming out fine. I just don't get it.

 

[Xmas]

The exhaustion is the uncontrolled contrast you are getting.

You are not warrent a repeated negative outside of Kodaks rule set!

If you read the instructions you get good negatives.

 

[mdarnton]

I have a batch of D76 I've been replenishing for over 2 years now. It's going fine. Adding the replenisher to the bottle first, then the developer goes back in, the bottle is always completely full. Currently I'm running an experiment replenishing D76 1:1 in a large sheet film tank. People get too scared too easily these days and apparently have no way at all to evaluate anything on their own, through experience. I attribute this to the rotten education system, combined with everything being done by pushing a switch on some electronic device with no idea of what's happening inside. I watch one forum when everyone freaks out any time anyone mentions any chemical, like death is just over the horizon. I read a news story Sunday that said something like 37% of people would call a plumber for a stopped up toilet! Ridiculous.
http://dhmo.org/
/rant

 

[fdonadio]

I read a news story Sunday that said something like 37% of people would call a plumber for a stopped up toilet! Ridiculous.

A couple of years ago (or so), I was talking to an electrician in a hardware store. He told me that one of his top customers is an engineer that doesn't know how to change a light bulb.

I am not sure if he was exaggerating or lying, or if the customer is too dumb or too lazy.

I guess this is the new, incredible world of technology we're living in.


Flavio

 

[MattKing]

A couple of years ago (or so), I was talking to an electrician in a hardware store. He told me that one of his top customers is an engineer that doesn't know how to change a light bulb.

I am not sure if he was exaggerating or lying, or if the customer is too dumb or too lazy.

I guess this is the new, incredible world of technology we're living in.


Flavio

I have to take off a significant portion of my car's front grill to change a headlight bulb.

For my wife's car, you need to have a car hoist to change a headlight bulb, because you have to do it from the bottom, through the wheel well.

It is easy to change the tubes in our kitchen ceiling fixture, if you have a tall enough ladder, and you can get the #%$/X## diffuser on and off the fixture.

And all the new homes seem to love to feature wonderful, lofted ceilings with light fixtures at least 12 feet off the floor.

So I sort of understand.

 

[mklw1954]

Using D76 stock solution, a $6 bag to make 1 gallon develops 15 rolls (4 rolls per liter, per the data sheet), for a cost of $0.40 per roll. In my opinion, the tiny savings in pushing it further is not worth the risk of shifts in development.

 

[fdonadio]

So I sort of understand.

The cases you mentioned are understandable. Even though I am a DIY'er (and my Honda's headlight bulbs are easy to change), not everyone has the knowledge, time or will to do things like that.

But, in my talk with the electrician, we were talking about plain incandescent or compact fluorescent bulbs!


Flavio

 

[37th Exposure]

I thought the capacity of D-76 is 8-10 rolls of 135-36 or 120 per liter? It is for Ilford ID-11 and Fomadon P (both are D-76 equivalents) and just about every book I have read state the same capacity. Old Kodak data sheets also say 10 rolls. The current sheet looks like they used the chart from the late Microdol -X by mistake. They look exactly alike. Who's right?

 

[MattKing]

I thought the capacity of D-76 is 8-10 rolls of 135-36 or 120 per liter? It is for Ilford ID-11 and Fomadon P (both are D-76 equivalents) and just about every book I have read state the same capacity. Old Kodak data sheets also say 10 rolls. The current sheet looks like they used the chart from the late Microdol -X by mistake. They look exactly alike. Who's right?

The Ilford capacity figure of 10 rolls per litre for ID-11 assumes that you increase the developing time by 10% for each and every roll after the first.
Kodak doesn't make any such recommendation for stock D-76.

 

[Kirks518]

According to the Kodak Tech Sheet for D-76, the yield I mentioned in the first post is based on a gallon (but then it says litre?), and it does say the yeild is with time compensation of 15% increase for every 4 rolls per gallon. It's on page 7 of the data sheet linked.

 

[Kirks518]

Using D76 stock solution, a $6 bag to make 1 gallon develops 15 rolls (4 rolls per liter, per the data sheet), for a cost of $0.40 per roll. In my opinion, the tiny savings in pushing it further is not worth the risk of shifts in development.

I agree it's cheap, but at the same time, why trash developer if it's still giving good results?

 

[MattKing]

According to the Kodak Tech Sheet for D-76, the yield I mentioned in the first post is based on a gallon (but then it says litre?), and it does say the yeild is with time compensation of 15% increase for every 4 rolls per gallon. It's on page 7 of the data sheet linked.

The capacity figures in J78 are expressed in rolls per gallon first, with rolls per litre following afterwards in brackets, as follows:

for stock D-76: 16 rolls per gallon (4 rolls per litre)
for D-76 1+1: 8 rolls per gallon (2 rolls per litre) provided that you should increase the development time by 15% after each 4 rolls.

In other words, the 15% figure only applies to D-76 1+1.

If you read through that section, and in particular the part that deals with replenishment, you will probably get the sense that D-76 was originally designed for large, high volume processing lines. The instructions specifically say you shouldn't "re-use" a batch of D-76 1+1 - that tells me that that 15% reference was directed to those who are developing large amounts of film in deep tanks.

In fact, all of those capacity figures are oriented toward deep tank use.

 

[Kirks518]

Matt, one of us is reading the chart wrong then.

Under "useful Capacity' on the chart of page 7, it says for Stock; "8x10 sheets in tray 16 (4)† " and "135-36 or 120 rolls in tank 16 (4)†‡ ".

Below the chart you'll see " † With time compensation; increase the development time by 15 percent after every (4) 8x10 sheets or (4) rolls per gallon processed"

The ‡ is if you add D-76R to stock after each batch, and specifically says not to increase times.

[QUOTE}In other words, the 15% figure only applies to D-76 1+1.[/QUOTE]

The sheet specifically recommends against re-use of 1:1, and the 15% increase applies to stock.

 

[MattKing]

Matt, one of us is reading the chart wrong then.

Under "useful Capacity' on the chart of page 7, it says for Stock; "8x10 sheets in tray 16 (4)† " and "135-36 or 120 rolls in tank 16 (4)†‡ ".

Sorry Kirk, you are right. In my defence, I'll plead small screen and fading eyesight - I had to switch to my desktop computer to properly differentiate between † and †‡.

It still doesn't bother me though that the Kodak capacity recommendation for D-76 may differ from its historical (pre-2002) recommendations and does differ from Ilford's recommendation for ID-11. A few things have changed over time with packaging and other factors, and ID-11 is different in packaging.

 

[DREW WILEY]

76 is odd in that it can rise in activity with oxidation, though it will eventually crash. That's why you either want to standardize on it completely
fresh, the same day, one-shot, or let it sit about a week, then use up all the solution within about six months, while it's on its plateau. This implies
keeping the primary stock solution fully air-tight bottled in the meantime, or in divided-up small airtight bottles for gradual use. I've never tried
replenishing it. You can buy a buffered version of 76 from Formulary which allegedly solves this problem. I don't use 76 much anymore. When I
did use it, it was primarily as an inexpensive non-tanning developer for unsharp masks, which can be nitpicky with target density, so I had to be
fussy about the developer activity itself. HC-110 is more predictable over time.

 

[Kirks518]

I agree about HC-110. Great stuff that lasts forever! The only reason I started with D-76 was I ran out of HC-110, and a guy was selling 14 packs of D-76 locally. I like it enough to keep using it, but I did really like HC-110 as a one shot. If I ever use these 14 packs up.....

 

[kb3lms]

I have 2 quart size glass bottles left from a gallon of D-76 stock I mixed in 2007. Most of one is now used and the other still hasn't been opened since mixing. I'd gotten distracted by other things and never used it up. It's turned sort of amber but it still works fine! Now I'm just keeping it to see how long it works. I'll use it for a small, insignificant piece of film from time to time just to see if it is really still any good..

 

[Xmas]

76 is odd in that it can rise in activity with oxidation, though it will eventually crash. That's why you either want to standardize on it completely
fresh, the same day, one-shot, or let it sit about a week, then use up all the solution within about six months, while it's on its plateau. This implies
keeping the primary stock solution fully air-tight bottled in the meantime, or in divided-up small airtight bottles for gradual use. I've never tried
replenishing it. You can buy a buffered version of 76 from Formulary which allegedly solves this problem. I don't use 76 much anymore. When I
did use it, it was primarily as an inexpensive non-tanning developer for unsharp masks, which can be nitpicky with target density, so I had to be
fussy about the developer activity itself. HC-110 is more predictable over time.

Not unique though as Microphen a D76 'clone' in PQ has the same 10 135x36 limit and the 12 or 13 will have elevated contrast...
Mybe the metal or pheodine is exhausted and you have a Hydroquinol developer residue instead