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Foma Pan 400 ASA fog on film???


Lemme understand. Are you blaming a film for massive fog where you use strange concotion of paper developers, pushed film and stored and exposed to the sun?
Wow!
 
lamerko said:
Both are Fomapan 200 still hanging to dry. There is nothing blue in the base. On the other hand, the anti-halation dye has an incredibly vivid bright green color - a joy to the eye
Click to expand...

Anyone want to say what the base density of Fomapan 200 is after processing? Their document might be talking about the dye that washes out.

I can trust that antihalation dye might wash out, I watch the water bath of TMY2 go from bright magenta/pink to clear in about four changes of water.

Example Kodak is about 0.05 base density while many of their 35mm films have 0.24 density that is permanent gray base.

That’s about 2/3 stop. Enough that you might want to knock a few seconds off contact printing times for 120 size negatives versus 35mm.
 
Alessandro Serrao said:
Lemme understand. Are you blaming a film for massive fog where you use strange concotion of paper developers, pushed film and stored and exposed to the sun?
Wow!
Click to expand...

Nobody knows. The motorcycle could have made the run from warehouse to store overnight.
 

https://www.foma.cz/en/fomapan-400 - Fomapan 400 datasheet

Minimum density varies greatly with developing temperature for Foma 400.
Second page shows densities for several developers at 30 degrees beside graphs for 20 degrees.
High temperature graph is at severe disadvantage due to very high min density and lowered max density.
Xtol and Fomadon Excel at 20 degrees will make it comparable to other film stocks while less common developers according to datasheet cause increased min density.

According to the graphs, min density tops at almost 0.5 for some developers at 5 minute mark for 30 degree graph. That value is surpassing by quite a bit min density of 11 minute developing time at 20 degree graph.

That reminds me of a thread from a year or two ago with Shanghai developed in non standard developer and having some serious issues that cleaned up in more standard chemistry.
Most of the time classic emulsions need to be developed carefully for repeatable results. Even more modern ones benefit from tight processing parameters.
 
Thanks @Light Capture the sheet explais the 120 base is clear with anti halation dye that washes out. Probably will give close to 0.05 densitometer reading. Like most 120 film, most are clear.
 
Bill Burk said:
Nobody knows. The motorcycle could have made the run from warehouse to store overnight.
Click to expand...

Alessandro Serrao said:
Lemme understand. Are you blaming a film for massive fog where you use strange concotion of paper developers, pushed film and stored and exposed to the sun?
Wow!
Click to expand...
It is the film ! and the issue is the paper backing of the 120 roll- there us a pre-rinse where the dye is washed out-the high temp is due to the room temp is 32-to-36 Celsius summer time. now the temp is down to 27Celsiusthis is not a problem...
3 films 400asa was the problem, out of 30rolls...
 

Fog is a thing, the backing paper is another issue. You were talking about massive fog at the opening of this topic as I see it...
As @Light Capture has clearly stated, fog gets high with higher developing temperatures.
I'd suggest you to not expose the film to direct sun or high temperatures, not to use strange paper developer concotions, use Kodak Xtol next time and I'm sure Fomapan 400 will be developed wonderfully. It's not the film the problem (except for the backing paper issue, but this problem was fixed by Foma).
 
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