Learned something today

[ChrisN]

I've been trialling some different developers, including some semi-stand routines, and have had trouble with uneven development, especially streaks associated with the sprocket holes - often called "bromide drag".

Well some of them are associated with the lack of inversion, and some were not what they seemed! Here's two scans of the same negative.

In this case the actual problem was fixer exhaustion - I'd lost track of the number of rolls fixed. Fresh fixer removed the streaks. There is still some underlying unevenness in the developing, but the fresh fixer gave me a usable neg. More traps for young players! 😀

 

[maddoc]

Thanks Chris for posting this valuable information ! I have never thought about this possibility yet.

 

[rover]

Only 8:30am and I learned something new already. Now what am I going to do the rest of the day?😉

 

[Tom hicks]

Yes , great info for those of us that have just begun .

 

[SciAggie]

Great information - thanks! What made you think of fixer?

 

[robklurfield]

I had the same problem. Took a couple of ruined rolls to realize it doesn't pay to be stingy with replacing fixer. Problem solved.

 

[rxmd]

Took a couple of ruined rolls to realize it doesn't pay to be stingy with replacing fixer.

Indeed it doesn't. Fixer is dirt cheap anyway.

Using water or acetic acid stop bath helps against fixer exhauption, too.

 

[skibeerr]

There is the Edwal hypo check. A small bottle gives you a few hundred tests for 10,5 euro.

Especially useful when fixing whet prints as you only see the bad fixing when the print turns grey.

http://www.macodirect.de/edwal-hypo-check-fixierbadtester-p-282.html

 

[Vics]

+one for Hypo Check. Works great

 

[FrankS]

It would be interesting for those of us with "ruined" film, supposedly due to bromide drag, to try refixing them. This would be worthwhile if anyone has an especially important negative that has this defect.

 

[Chinasaur]

N00bie question: How does fixer exhaustion contribute to making those striations in the negative? They seem very defined and delineated.

 

[FrankS]

It has to do with chemical activity and exhaustion in those localized areas of the film. Sprocket holes are an opportunity for fresh chemical to flow over the localized film surface to a greater extent than other areas. There is more replenishment of exhausted chemicals with fresh chemicals. This results in uneven chemical action.

 

[tlitody]

It would be interesting for those of us with "ruined" film, supposedly due to bromide drag, to try refixing them. This would be worthwhile if anyone has an especially important negative that has this defect.

I don't think that's bromide drag. It's surge marks from inverting too slowly so that developer flows through sprocket holes causing extra development where it flows over film.

When I invert I use parabolic motion curve like a ball being thrown from one hand to the other as in juggling. At the top of the curve the developer becomes weightless and at that point I invert the tank quite quickly. The developer then just falls to the bottom of the tank rather than flowing through sprocket holes.

 

[FrankS]

I don't think that's bromide drag. It's surge marks from inverting too slowly so that developer flows through sprocket holes causing extra development where it flows over film.

When I invert I use parabolic motion curve like a ball being thrown from one hand to the other as in juggling. At the top of the curve the developer becomes weightless and at that point I invert the tank quite quickly. The developer then just falls to the bottom of the tank rather than flowing through sprocket holes.

Right. But then how do you explain the original post?

 

[tlitody]

Right. But then how do you explain the original post?

Exhausted fixer but those surge marks are still there albeit much less obvious.