Thin negatives with fresh id-68/ what is the active ingredient in bw developing

MingMingPhoto · Jul 31, 2024

hey guys!

so I've been making id-68 to develop all my film for the past 5 months or so.

at first I made it in 1L quantities but I've been doing 5L.

recently the last two batches of 5L containers I made were not potent at all. film came out super thin on freshly made chemicals.
first time it happend I processed another batch of films - thin. then I dumped the 5L made a new 5L and let it sit over night. same thing when I developed the next day.

one thing I've noticed is the phenidone is very brown. it was originally white, but I've made plenty of batches with the brown phenidone before with great results. so I'm not too sure if it's that or not.

does anyone any idea what it could be?

ingredients include
sodium sulfite
hydroquine
borax
boric acid
phenidone
potassium bromide
water

aside from time, all other variables remain consistent

Anon Ymous · Jul 31, 2024

ID68 has two development agents, hydroquinone and phenidone. Your phenidone is "very brown" and is the likely culprit. Try sourcing some fresh and mix another batch.

RalphLambrecht · Jul 31, 2024

Anon Ymous said:
ID68 has two development agents, hydroquinone and phenidone. Your phenidone is "very brown" and is the likely culprit. Try sourcing some fresh and mix another batch.

that would be my proposal too.

MingMingPhoto · Aug 1, 2024

RalphLambrecht said:
that would be my proposal too.

Anon Ymous said:
ID68 has two development agents, hydroquinone and phenidone. Your phenidone is "very brown" and is the likely culprit. Try sourcing some fresh and mix another batch.

Is there any way to tell before hand if the phenidone is bad or good? Or a shelf life once opened?

koraks · Aug 1, 2024

MingMingPhoto said:
does anyone any idea what it could be?

Could be anything, but the brown phenidone doesn't sound too good.

MingMingPhoto said:
Is there any way to tell before hand if the phenidone is bad or good?

Not really, but I haven't had phenidone go brown. How'd you manage that? How do you store it? Mine is in brown glass bottles with a properly sealing cap. Its color is either white or very pale yellow, and the color is stable over the years. I can see how it might go bad if it's allowed to get moist.

Also, as I understand, you're running a commercial operation. In your place I'd strongly consider the option of buying factory-made developer in order to remove a few failure modes. Many of us (myself included) are hobbyists and if we waste a roll or two of film due to a failed experiment, so be it. In your case, I understand (correct me if I'm wrong) you serve your customers with your processing services, and I'd feel pretty embarrassed if I had to explain I messed up their film because my DIY developer somehow didn't work.

At the very least, if you use DIY developers, do a clip test on a new batch to verify its activity is on part with a known-good batch. Pick a particular type of film, take an inch of two of this and develop it for e.g. 2 minutes in (good!) ID68 1+1 in room light. Measure its density with a densitometer (or determine its density with a scanner or contact print and a step tablet). Then perform the same routine on any new batch of developer. It's even better if you also control exposure, so instead of doing the whole thing in room light, actually expose some film to a step wedge or in a camera and process that in the new developer. Still, the room-light approach will tell you if you're in the ballpark and is quicker & easier to do.

Just my $0.02 - make of that what you will. I'm just rooting for your business to continue being a success and your reputation developing into a solid one.

MingMingPhoto · Aug 1, 2024

koraks said:
Could be anything, but the brown phenidone doesn't sound too good.

Not really, but I haven't had phenidone go brown. How'd you manage that? How do you store it? Mine is in brown glass bottles with a properly sealing cap. Its color is either white or very pale yellow, and the color is stable over the years. I can see how it might go bad if it's allowed to get moist.

Also, as I understand, you're running a commercial operation. In your place I'd strongly consider the option of buying factory-made developer in order to remove a few failure modes. Many of us (myself included) are hobbyists and if we waste a roll or two of film due to a failed experiment, so be it. In your case, I understand (correct me if I'm wrong) you serve your customers with your processing services, and I'd feel pretty embarrassed if I had to explain I messed up their film because my DIY developer somehow didn't work.

At the very least, if you use DIY developers, do a clip test on a new batch to verify its activity is on part with a known-good batch. Pick a particular type of film, take an inch of two of this and develop it for e.g. 2 minutes in (good!) ID68 1+1 in room light. Measure its density with a densitometer (or determine its density with a scanner or contact print and a step tablet). Then perform the same routine on any new batch of developer. It's even better if you also control exposure, so instead of doing the whole thing in room light, actually expose some film to a step wedge or in a camera and process that in the new developer. Still, the room-light approach will tell you if you're in the ballpark and is quicker & easier to do.

Just my $0.02 - make of that what you will. I'm just rooting for your business to continue being a success and your reputation developing into a solid one.

ah I defiantly let it get wet (lowkey was also doing so to see if it would cause issues.) but yeah I did a clip test the moment the phenidone turned brown and then devloped and saw everything was ok so so I was under the assumption borwn was ok. but good to get the info that yours remains yellow/white. I'll ope na new bottle and be more careful. and I'll start doing the densitometer test consistently as well ty for the advice

Anon Ymous · Aug 1, 2024

MingMingPhoto said:
Is there any way to tell before hand if the phenidone is bad or good? Or a shelf life once opened?

Perhaps if you tried a phenidone only developer, but AFAIK these are special purpose, low contrast developers, not general purpose. I bought mine 10 years ago and it has practically remained unchanged, a light yellow colour. Very brown sounds pretty bad for phenidone. Shelf life should be very good, provided that it is kept dry, under relatively normal temperature and air tight.

MingMingPhoto · Aug 2, 2024

Anon Ymous said:
Perhaps if you tried a phenidone only developer, but AFAIK these are special purpose, low contrast developers, not general purpose. I bought mine 10 years ago and it has practically remained unchanged, a light yellow colour. Very brown sounds pretty bad for phenidone. Shelf life should be very good, provided that it is kept dry, under relatively normal temperature and air tight.

verdict, I did a comparison of the developer as it was and then + fresh phenidone. it was the phenidone. I'll be more careful to keep it from moisture

Thin negatives with fresh id-68/ what is the active ingredient in bw developing

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