Topic: Surge marks 35mm

[choppert]

Hello all,

Just devved a roll of tri-x and think I've got surge marks from the sprocket holes.

On reflection some of my agitating was fairly enthusiastic!

Anyone got the a good description on how gently/fiercely to agitate a daylight tank?

(I'm thinking I should avoid anything that could be considered fierce?   )

Chops

[original_ann]

I'm not sure what 'surge marks' are but I tend to invert and right the tank without any hard jolt. 

[choppert]

Notes

Tri-X in dilution B of HC-110

7 minutes at 17C
'Vigorous' 30s agitation at the start
Three quick and sharp inversions (lasting about 5s) per minute

I imagine this is largely bad form?

Chops

[Francois]

Well, I use the Tai-Chi method of agitating (doing orbital spins) with a nice hand tap on the bottom before resting. Continuous agitation for 1 minute with plenty of taps. Then 5 seconds every 30 seconds.

Never had any film marks with that...

[choppert]

Here are a couple of snaps of the negs.

The BURNS file shows that on the first half dozen negs there are queer areas at the bottom of the images with absolutely no information in.  It's almost as though something has burned the image off the negs.  Just the first half dozen and only at the bottom!

The STREAKS file shows the streaks from around the sprocket holes - more prominent at the end of the film (though that may be that the images just show the streaks up more!)

I'm quite confused, to be honest.  Can over-agitation cause these two problems?  To the extent that information has been 'washed' off the negs?  Very odd.

Leon - over to you...

Chops

[Francois]

Usually, overagitating tends to make black streaks.
This one has me wondering if it isn't a combination of not enough chemistry and too much agitation?

[Fedo]

Choppert,
             I had a phase of getting dark streaks running from the sprocket holes on my negs & eventually found out that I was agitating the fixer too little.

I know that because another student was processing a film at the same time and using all the same chemistry. after I got streaks & he didnt, I realised he had agitated after adding the fixer & I hadnt. I re-fixed and the streaks dissappeared.

Your streaking doesnt look quite the same really but I thought it was worth pointing out that too little agitation can cause problems just as much as too much agitation!

[astrobeck]

well, I just dug through the archives to find this...and it saved my negatives just a few minutes ago!
I had the dark streaks mentioned, so I re-fixed and they are gone!
Whoosh!
Also, I'm wondering ..Francois, do you still use the Tai Chi method of agitation?

[Francois]

Yep, always the same.
I feel that sometimes inversions are too aggressive. Also, you can't invert if your tank leaks around the lid or if you use stainless.
I also bump it on the bottom to dislodge the air bubbles. So far this has worked very well for me. But I have to be careful because it's also possible to overagitate while doing so. But I, never agitated so much as to get streaks and believe that it might be impossible to do with this technique... too much randomness in the movements.

[Kai-san]

I don't think this phenomenon has got anything to do with inversion techniques, this is a fixer problem. When I started developing my own films I made the same error, not agitating the fixer properly. Since I now mainly use Kodak Xtol I do the Kodak Flip; rather quick 180 degree inversions (4 inversions in 5 seconds). After each round of inversions I slam the tank against the table top because the Xtol process creates bubbles. I have never had any streaking like this on my films.

[Francois]

I've actually seen a tank rupture once from being banged on the table. That's why I use the palm of my hand.

[Indofunk]

I place an old tshirt on the countertop before tapping it, because I found that sometimes the black plastic from the tank leaves little marks on the countertop. Also I like to think that the tshirt deadens the sound a bit from my quick-to-complain neighbors

[Francois]

You could always hide the sound behind some trumpet practice
Though it would be hard to do both at the same time