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Lost Contrast - Help !
I appear to have suddenly lost print contrast in my process - and I'm at a total loss.
My enlarger is an Ilford Multigrade 500 head on a D5500 chassis. My standard print developer is an "Easy 130" which I prepare by adding 20 g sodium sulfite, 45 g glycin and 2.5 g BZT to a gallon of Dektol stock. I dilute 1+2 and develop prints for 3 minutes at 21 deg. C. Suddenly, both Grades 2 and 2½ are printing at Grade 1 contrast.
I tried a working strength at 1+1 and extended development to 5 minutes - still Grade 1. Next I redid the safelight test by covering a piece of paper exposed to a threshold level of light with a coin for 7 minutes - no issue. I then changed both lamps in the enlarger - no difference! Next, I exposed a series of prints in my D 5 with a dichroic head at various degrees of magenta filtration and found the following: 25M - Grade 1; 75M - Grade 2½ and 100M - Grade 3. I then repeated this series with a newly mixed batch of straight Dektol 1+2 with 3 minutes development. Again - no difference. In fact a Grade 1 exposure of 60 Y gave me an ISO range of 195 which is a Grade 00 !
I had used some older paper originally, (only 6 months old, mind you.) Just in case I bought a new box of MGIVRC Glossy which I received only a couple of days before the final tests. The grades were determined by printing a 4x5 Stouffer 31 step wedge.
I can't think what else to try. It must be in the process somewhere because this low contrast problem occurs across two separate enlargers. I really don't want to start over-developing my film just to attain mid-range contrast on a "Grade 2½" paper.
It's probably something stupid that I've overlooked - but I'm damned if I can think what it is?
H-E-L-P
Thanks a lot
Bob
"Why is there always a better way?"
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You tried this with brand-spanking new, fresh developer? Temperature's ok?
*twilight zone music*
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Yup - It's driving me nuts ! (Not like I wasn't nut's anyway  )
"Why is there always a better way?"
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 Originally Posted by BobNewYork
My standard print developer is an "Easy 130" which I prepare by adding 20 g sodium sulfite, 45 g glycin and 2.5 g BZT to a gallon of Dektol stock. I dilute 1+2 and develop prints for 3 minutes at 21 deg. C. Suddenly, both Grades 2 and 2½ are printing at Grade 1 contrast.
Originally Posted by BobNewYork
Yup - It's driving me nuts ! (Not like I wasn't nut's anyway )
You're not accidentally mixing sodium thiosulphate instead of sodium sulfite into your developer? 
Could be an interesting result, if you mix fixer into your developer...
My website
" The nineteenth century began by believing that what was reasonable was true, and it wound up by believing that what it saw a photograph of, was true." - William M. Ivins Jr.
" I don't know, maybe we should disinvent color, and we could just shoot Black & White." - David Burnett in 1978
" Analog is chemistry + physics, digital is physics + math, which ones did you like most?"
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No Marco - I don't have any hypo. I use ammonium thio liquid. I thought of that and gave all my trays a ludicrously serious wash just in case. Not that I don't wash them well after each session.
Bob H
"Why is there always a better way?"
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Originally Posted by BobNewYork
No Marco - I don't have any hypo. I use ammonium thio liquid. I thought of that and gave all my trays a ludicrously serious wash just in case. Not that I don't wash them well after each session.
Bob H
But your "sodium sulfite" is not some new buy, possibly from a less reputable or clear origin? It would be all to easy to mix up sodium sulfite with sodium thiosulfate. Not only the names are slightly alike, the chemical formulas look quite similar too...
And there is even related substances like sodium bisulfite and sodium metabisulfite, used in for example wine making to complicate things , although I don't think a mix up with these would cause your issues, as they seem to have functions similar to sodium sulfite as oxygen scavengers / antioxidants
My website
" The nineteenth century began by believing that what was reasonable was true, and it wound up by believing that what it saw a photograph of, was true." - William M. Ivins Jr.
" I don't know, maybe we should disinvent color, and we could just shoot Black & White." - David Burnett in 1978
" Analog is chemistry + physics, digital is physics + math, which ones did you like most?"
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You're right that the sodium sulfite is not new - although it is only about 9 months to a year old. It came from Photographer's Formulary here in the U.S. who are very reputable and I've certainly had no issues with them before. I had wondered if my eyes were really going - so I actually had someone else count the wedge steps for me to calculate the ISO range and grade !!
The reason it's so important to me is that I want to try some Pyro developers and, as I print on VC paper I'm likely to need more contrast availability - not less.
I can hear your brain whirring Marcos like mine has been !! Appreciate the interest.
Bob H
"Why is there always a better way?"
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My website
" The nineteenth century began by believing that what was reasonable was true, and it wound up by believing that what it saw a photograph of, was true." - William M. Ivins Jr.
" I don't know, maybe we should disinvent color, and we could just shoot Black & White." - David Burnett in 1978
" Analog is chemistry + physics, digital is physics + math, which ones did you like most?"
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Sorry Marco !!
It was unintentional - but an unintentional insult nonetheless !
I'll try to do better in future - promise 
Bob H
"Why is there always a better way?"
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Temperature of the developer OK? When my developer drops below 60 degrees the same thing happens. But my darkroom is cold, don't know what the setup is.
When you tried with Dektol, was that freshly mixed?
Can you go to a nearby store and try a bottle of Ilford Multigrade developer? Just to be sure it isn't your chemistry.
Sure sounds weird.
- Thomas
"...the heart and mind are the true lens of the camera".
- Yousuf Karsh
"We are what we repeatedly do. Excellence, then, is not an act, but a habit".
- Aristotle
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