What causes streaking on negative?

[Andrew Billy]

Hi all!

I continue to process c41 at home. I am very consistent with the temperature, developer at 100F, Blix around 102-105F, wash at 100F, stab at room temp. I always prewash at 100F, soak it 1 - 3 min before pour in developer, and I use photo Flo before hang dry. All chemicals mixed with distilled water. I use a plastic Arista developing tank with a plastic reel for 120 film. I use the little plastic spinning rod insert into the center of the tank, turning it for agitation. I have been noticing uneven development, streaks showing up mostly in the sky portion of landscape pictures that have blue skies. I examined the negative by holding them up to a light source (my table lamp) and couldn't notice any streaking. Could anyone shine a light as of to what I am doing incorrectly? Any ideas would be appreciated!

 

[bdial]

Are you turning in one direction only, or back and forth?

 

[Jeff L]

I would try a stop bath after developer. This was recommended to me by Photo Engineer some time ago. It got rid of the steaks I was getting and improved the quality of my negatives. Stabilizer should be the last step and not photo flo. This is important for the longevity of the negs. I use a little photo flo in the stab. I understand if Kodak stabilizer is used, you won't need the photo flo added. Someone correct me if I'm wrong on this.
Addition: I also invert tank for agitation.

 

[bvy]

That looks like a drying mark to me. Ditch the stabilizer and Photo-Flo and use Kodak Final Rinse.

 

[Andrew Billy]

I turn one direction only.

I use the Unicolor c41 kit. comes with developer, blix, stab. Stop Bath for c41, could I use same stop bath for B&W processing?

 

[Jeff L]

I used Kodak indicator stop bath right after developer with no rinse. The idea is to get the development stopped fast.
It helped my negs for sure. There are other threads on this is you want to read more about it. Make sure you agitate well/properly too

 

[MattKing]

Don't use Photo-flo (or anything else) after stabilizer. It will just wash the stabilizer away, leaving the film vulnerable to bacteria.

 

[georgegrosu]

„I examined the negative by holding them up to a light source (my table lamp) and couldn't notice any streaking.”
In the negative film, the image has a contrast about 3 times smaller than the positive image.
The negative color film has a yellow-orange color fog.
So it's pretty hard to notice this problem with a magnifying glass in the negative.
Try to increase the negative with a magnifying device.

George

 

[Sirius Glass]

Turn in both directions. Use stop bath. Use stabilizer. Do not use squeegees.

 

[dario]

Streaking can result from inadequate agitation. It's especially evident around the sprocket holes of 35mm film, especially if the tank is full or nearly full (as when developing two films in a two-reel tank). The solution is to agitate by inverting the tank and to use a tank big enough so that the developer drains completely out of the film when the tank is inverted. I use a 3-reel tank when developing a single roll of 120, use just enough developer to cover the film, agitate by gentle inversions of the tank, and never have a streaking problem. Just a thought.

 

[Andrew Billy]

Thank you guys so much! I will change my methods of agitation and start to use stop bath. One more question, I prefer using the spinning rod for agitation instead of inverting the tank because in the past I have gotten overexposure on both edges of the film, and I suspect its because my method of inverting the tank is too strong that causes the edges to over develop? Does gentle inversion means invert the tank slowly for 3 - 4 rotations? Thanks!!