processed several roll of 120 TMAX 400 what is this banding on left through the neg?

Been processing 120 and 135 TMAX for a few months with same equipment with a few minor scratches here and there but this turned up last night.

Is it possibly X Ray fog, change bag fogging, processing tank or something else? Two reels processed in ID-11 came up with this through left of the neg.

Obviously need to know what I have done wrong before I continue with last ten rolls. The 1st 3 came out fine the day before although there is a minor X ray zig zag ghost from film being X ray fogged months earlier on arrival from USA in luggage. I have been able to photoshop those images.
The two rolls were shot a few days apart so in camera fogging unlikely.

I used a change bag to a Patterson tank and processed required time in ID-11 stock.

Thanks

Fog would look darker on the neg and lighter on the print.

I would have said that the film wasn't completely covered with developer. Either too little developer solution in the tank, or the reel slipped up the central pole/pipe (if applicable/possible with your tank). But if the two reels were in the same tank at the same time, this would happen only to the film at the top.

Yes I think I might have had to little developer in the tank. Measured out 350mm for the tank on these rolls, others previous I just poured in and kinda topped up. The reel could have slipped up pipe will check that. Thanks!

Usually, I never pour in "just the required amount" of developer into my tanks when developing. 350 ml becomes 500ml and 500lml becomes 600-650ml. It's less economical, indeed, but at least you will avoid the large portions of problems like this.

You can get a plastic collar to put onto the spool-core, to avoid the reels from slipping, I had one and I can see that it's very easy to loose them too!

Also, by using inversions of the tank, rather then the swivel-stick, you also reduce the risk of not covering the negative uniformly and sufficiently with developer.

Paterson tanks require 500 ml for 120 film.

biginvegas said:

to little developer in the tank.

Click to expand...

+1.
Possible problem with the same outcome is when you have developing tank that can accept more reels, and you put one reel only and it is not firm on the place. You could have enough amount of developer, but reel is too high in the tank (traveled up during agitation), and you get the same result.

EDIT: you can try to compensate the problem in printing stage with dodging/burning the area of the negative.

ooze said:

Fog would look darker on the neg and lighter on the print.

I would have said that the film wasn't completely covered with developer. Either too little developer solution in the tank, or the reel slipped up the central pole/pipe (if applicable/possible with your tank). But if the two reels were in the same tank at the same time, this would happen only to the film at the top.

Click to expand...

I see you were faster than me - I just wrote the same stuff .

Yup just figured that out the hard way. Last batch came out just fine. Thanks for quick responses!