Lost Contrast - Help !

BobNewYork · Feb 25, 2011

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

holmburgers · Feb 25, 2011

You tried this with brand-spanking new, fresh developer? Temperature's ok?

*twilight zone music*

BobNewYork · Feb 25, 2011

Yup - It's driving me nuts ! (Not like I wasn't nut's anyway )

Marco B · Feb 25, 2011

BobNewYork said:
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.

BobNewYork said:
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? :confused:

Could be an interesting result, if you mix fixer into your developer...

BobNewYork · Feb 25, 2011

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

Marco B · Feb 25, 2011

BobNewYork said:
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 :confused:, 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

BobNewYork · Feb 25, 2011

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

Marco B · Feb 25, 2011

BobNewYork said:
I can hear your brain whirring Marcos like mine has been !! Appreciate the interest.

Bob H

Marcos was that dictator that went away, as Gaddafi should, but he doesn't realize it yet...

My name is Marco...

By the way, you don't give info about the Dektol, is that fresh? You only write you mixed up new from stock, but is the stock OK?

BobNewYork · Feb 25, 2011

Sorry Marco !!

It was unintentional - but an unintentional insult nonetheless !

I'll try to do better in future - promise

Bob H

Thomas Bertilsson · Feb 25, 2011

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

BobNewYork · Feb 25, 2011

I think I will try a bottle of chemistry from a local store, (if I can find one !!!) As for temperature, the dev was a little warm if anything 'cos I made it from the hot, new stock solution. It is weird - bit like me !!

Ian Grant · Feb 25, 2011

Check your enlarger lens, at this time of year a cold lens can get condensation inside as it's used and warms up. At worst you get physical condensation you can see, but more invidious is it happens and dries leaving a film of minute dust particles - this happens a few times and you have a hazy lens giving low contrast.

That's speaking from experience, it's happened to me, luckily my lens was easy to take apart & clean. Now my lenses are stored in the warmth.

We've had a couple of threads like this before this time of year

Ian

Athiril · Feb 25, 2011

Marco B said:
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 :confused:, 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

Sodium Bisulphite punches you in the face with sulphur dioxide when you open the container or mix it in water, so you should be able to tell quite easily

archer · Feb 25, 2011

Dear Bob;
eliminate the BZT and try again.
Denise Libby

Thomas Bertilsson · Feb 25, 2011

This could be easily tested by making a contact sheet. If the contact sheet has good contrast and the enlargement doesn't - you know it's the lens.

- Thomas

Ian Grant said:
Check your enlarger lens, at this time of year a cold lens can get condensation inside as it's used and warms up. At worst you get physical condensation you can see, but more invidious is it happens and dries leaving a film of minute dust particles - this happens a few times and you have a hazy lens giving low contrast.

That's speaking from experience, it's happened to me, luckily my lens was easy to take apart & clean. Now my lenses are stored in the warmth.

We've had a couple of threads like this before this time of year

Ian

BobNewYork · Feb 25, 2011

Thanks All :

I had eliminated the BZT Denise when I just mixed a new stock of straight Dektol. So that went out when I dumped my "Easy 130". I've also been adding the BZT at that rate for quite a while now to cool the print tones without issue.

As regards the lenses Ian, I made some 8x10s from negs as well as the step wedge and they were pretty sharp. In fact, I'd been out of the darkroom for about 6 weeks and I just ran some film tests with GSD-10, (How else to use the extra Glycin ??) The contact proofs gave me a problem. I couldn't understand why my max. black exposure resulted in a very weak E.I. and blown out highlights after 75 minutes semi-stand development at 21 deg. C. Of course Grade 00 will do that for you !!!

I'm coming down to the Dektol itself. I usually buy 30 or so gallon packs at a time and my last purchase was probably 12 - 18 months ago. Having said that, the powder is pure white and I've certainly seen ultra-old Dektol in the past where the powder is brown. No hint of that here - nor in the color of the freshly mixed stock solution.

Perhaps I'll just restrict myself to long range subjects on bright sunny days! either that or shoot myself

Really appreciate the collaboration all.

Bob H

ic-racer · Feb 26, 2011

BobNewYork said:
Suddenly, both Grades 2 and 2½ are printing at Grade 1 contrast.

I'd just increase the contrast on the head to get the results you want.

BobNewYork · Feb 26, 2011

Yeah, I hear that. My concern is that if I have to print "normal" contrast negs on a Grade 4 setting, I have no room to play with for flat negs or scenes. My alternative would be to essentially overdevelop all my films so that they print easily on Grade 0 (My Current Grade 2) - but that too has its downsides. I'm calibrating some new film/dev combos and I've always done this so that normal negs print well on Grade 2 - 2 1/2. The idea is that this gives me room for those long and short DR scenes when they occur. I can print existing negs OK by raising the contrast as you say. But I'd really rather nail this issue down so I don't have to do workarounds on a permanent basis.

BTW I just noticed that in my last post made late, (for a man MY age !!!) last night I said blown out highlights. I meant, of course real dull and dingy highlights.

winger · Feb 26, 2011

There isn't any chance you accidently left a filter in the drawer and are using more than one? Don't ask why this is my thought.

Doremus Scudder · Feb 27, 2011

And nobody has mentioned dichroic filter degradation either... If you are using a dichro head, try doing your tests with regular multigrade filters or the like (newer ones). May the magenta filter in your head has faded or is not being positioned properly by the dial. Just a thought. You could try some graded paper too, just as a control.

Good luck,

Doremus Scudder

Nicholas Lindan · Feb 27, 2011

Do you get the same results if you eliminate the enlarger from the equation -- say by making a contact print with a non-enlarger light source?

BobNewYork · Mar 1, 2011

Good suggestions all - I really appreciate them. Filter degradation on the blue-filtered lamp would certainly account for it. Unfortunately, the Ilford MG head doesn't produce white light under any circumstances so I can't use separate filters. I also had a thought that perhaps the lamp holder on the blue lamp needs replacing. I'll try putting a meter across the terminals later and see if it tells me anything. It must be either the process or the enlarger and I'll have to identify which. I'd rather be out taking photographs - but it's a little pointless until I get this sorted!

Thanks again

Bob H

Ronald Moravec · Mar 3, 2011

compare the highlight density of your neg with the step wedge. You will know if it the negative or the paper. At least close.

eclarke · Mar 3, 2011

You have Glycin, why not just make some 130? I pump up the carbonate to 80g/ liter of anhydrous and replace the bromide with 15cc of 1% benzotriazole solution. Soup at 1+3, 73 deg. and you'll get all the contrast you can handle..EC

Lost Contrast - Help !

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