Negative Streaks

[LCSmith]

I wonder whether I might solicit opinion from the pool of expertise. Behold a crop of a rather unremarkable photograph of two remarkably cheerful folk strolling Greenwich Village on a halcyon Saturday in early March. Behold the dark vertical streaks in the space above and between their heads. What could account for such streaks? My first thought is that I need to change the fixer.

Any thoughts would be received with much gratitude.

Here are the specifics of the exposure and development.

Leica iiiF
50 Summicron
f/5.6 1/500s
TMAX 400
Yellow Filter

HC-110 Dilution B (1:31)
5.5 minutes at 20 degrees celsius

 

[sreed2006]

My first guess is that development was done in a daylight tank, and agitation was done by simply inverting the tank, without giving it a twist as the tank was inverted (by twist, I mean doing a spiral motion along with flipping the tank upside down and back). My second guess is that it is not the fixer.

Edit to add: If you suspect the fixer, then you can run it again through fresh fixer and see if that removes the streaks.

 

[Chriscrawfordphoto]

Insufficient agitation.


Here's a video I made showing how I agitate.


https://youtu.be/tOUUO3dDLqA

 

[LCSmith]

Ah yes, thank you both for your responses. I agree that it may be an agitation issue.