Welcome to Photrio!
A cyan cast like that is often the result of blix carryover into the developer. Have you eliminated any possibility of contamination of your developer?
Another possibility is fogging due to use of a safelight. If you're not already doing so, please ensure you're handling the paper in a completely dark environment until it emerges from the blix bath.
Given the pattern of the cyan cast, I have a feeling your paper is being fogged by red or orange light during handling.
The colour cast is on the unexposed parts of one of your prints, so is it possible that the colour paper gets fogged in the darkroom between printing sessions, say by a yellow (amber) light?
I left the racks in the processor ever since pouring in the chemicals yesterday around noon.
Also, every now and then I get a nicely white unexposed test strip, but not consistently...
I've left the boxes on the table next to my enlargers in stead of storing it back in the closet.
I wonder if timsch did decide on what the cause was?
pentaxuser
As you well know, we might wonder forever, and doing so out loud will not change a thing (doing so silently won't, either).
Given the fact that it's now mid-July and he was working on his Master's project, @timsch most likely has resolved the issue by now one way or another.
Very old thread, but I had run into a very similar issue in a Thermaphot ACP 404. Uneven cyan streaks all across every sheet, in different shapes/streaks too. Sending through an entirely unexposed sheet still gave the streaks, so not a fogging issue.
View attachment 392362
(in the screenshot above, ignore the yellow D-min issue, it was due to an expired box of paper that Fuji sold new)
For me it was solved by adding glacial acetic acid to the blix tank to act as an additional stop bath. I spoke with a mentor of mine with much more experience than me, and here's some more of his correspondence as to why it was happening:
The fact that you are getting a form of mottling or streaking makes me think the bulk of the problem is at the entrance to the BLIX tank where developer carry-in eventually (too quickly) can momentarily overpower the "stop bath" effect as rivulets of only partially neutralized develop continue to follow the paper's plunge into the BLIX causing uneven over development. The larger the sheet (width & length) of the paper the greater the unevenness.
I still think the problem is at the entrance to the BLIX. A spray bar kluge might be in order but without actually seeing it, I don't know if it is possible. How well "squeegeed" is the paper exiting the Dev. tank? Could be a factor.
You could try lowering the pH of the BLIX gradually. Although difficult to measure pH in a colored solution, you could add measured amounts of glacial acetic acid (be careful with it!) starting with a liter (make sure mixed in completely) and then a second liter. Without knowing the actual BLIX tank capacity nor the outcome of the first test at a liter this is only an estimate at a distance. You could always backtrack the pH with some KOH if the pH lowering makes the chemistry go south.We also ruled out chemical contamination as we had mixed everything fresh and the cyan smearing was still ever present. Adding glacial acetic acid to the blix bath completely solved the smearing, though it took us some trial and error to figure out the least amount we had to add. We arrived at adding 50ml of glacial acetic acid per 4.5L of blix (our processor's tank size).
50ml of glacial acetic acid per 4.5L of blix
That's quite a lot. I honestly wouldn't go there.
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?
We use cookies and similar technologies for the following purposes:
Do you accept cookies and these technologies?