120 Negatives darker on the edge of frames ? What am I doing wrong ?

Hi all.

I've been having a problem lately with my 120 Tri-x 400 negatives. It seems that the edge of the frames are more dense and I'm not sure why. I'm assuming it is something to do with my processing procedure. I've attached a couple of examples. Can anyone tell what I am doing wrong here ? Could it be a problem with my film back? I am using a hasselblad 500c/m.

My basic process is as follows:

1. Tri -x 400 in Rodinal 1:50 for 12 mins
2. Tap water rinse for stop bath.
3. Fix for 10 mins in tetenal vario fix
4. Wash for film for 10 mins (running water through pipe into patterson tank)
5. Let film sit in photo-flo for 90 seconds
6. Hang up and dry in dust free area

Describe your agitation procedure please.

PhotoJim said:

Describe your agitation procedure please.

Click to expand...

I spin the reel in the patterson tank using the little drop-in plastic handle. I twirl it slowly for the first 30 seconds and then 10 seconds every minute there after.

Thanks.

Don't do that. Put the soft plastic cap on the lid after you've poured in the developer, rap the tank on the counter firmly to dislodge air bubbles, and then invert once a second until the first minute of development is done. Then let it rest until another minute is up and give it ten agitations in ten seconds (inversion again). Continue doing this once a minute until a minute remains, then begin to pour out the chemistry when about 10-15 seconds remain.

1. Present on every single frame?
2. Present *between* frames?

If the latter, it's the camera.

I think you have a problem with your back, possibly at the dark slide slot.
Without another back to check or confirm this...use tape on the back you have.

With a fresh roll of film loaded into your existing back, mount the back to your camera,
but don't advance to the first frame.
Next, with the back attached to your body, remove the dark slide.
Now, run a layer of black tape round the interface between the camera and the body,
covering the dark slide slot. Shoot the whole roll. See if the problem has been solved/identified.

This is a quick, cheap and easy method of elimination, or trouble shooting the problem.
Probably time for a light-seal kit.

Marc

Thank you for the suggestions everybody. I will try inverting my tank rather than using the spinner stick thingo and I'll test the film back for light leaks. I'll post back with my results.

Regards,
Jonno

What others have described about agitation is to eliminate "surge", or excessive development in the side areas of the images, parallel to the long edges of the film, which can be troublesome with 120 film, more difficult to avoid than with smaller film.
But the tower image is troubling to me. If this is shot vertically, then the area at the top of the frame would not be surge, and is rather strange looking. Are these straight prints?

I had a very similar problem, just with one roll of a batch in C41. ( The other rolls did not show this problem)
I use the Rollie C41 kit
Taken with a Nettar folder.
I also use the rotating stick. Maybe next time I will try inversions
On one photo the edges of the frame are light, on the other photo it is on the end between frames.

I had this identical problem with 120 roll film with a stainless steel tank and reel. I used 2 inversions every 30 seconds. When I switched to using a Jobo for film development, the problem completely resolved. For those who have had success with 120 roll film and stainless steel reels and tank, I am curious to know what inversion methods have worked for you?

Vivaldi said:

I had this identical problem with 120 roll film with a stainless steel tank and reel. I used 2 inversions every 30 seconds. When I switched to using a Jobo for film development, the problem completely resolved. For those who have had success with 120 roll film and stainless steel reels and tank, I am curious to know what inversion methods have worked for you?

Click to expand...

Slower inversions, load so that the reels do not slosh around inside the tank.

Vivaldi said:

For those who have had success with 120 roll film and stainless steel reels and tank, I am curious to know what inversion methods have worked for you?

Click to expand...

I had problems with even development of 120 roll film with stainless tanks and reels UNTIL I started doing the following.

I only load the tank to half capacity, both with film and developer. For example: If I am using a two reel tank I only load film in the bottom reel (I keep the 2nd reel on top and empty as a spacer) I use 500ml of developer (or whatever it takes to cover only the bottom reel). I agitate (for the first minute then once a minute there after) by tipping the tank 90degrees left, right, forward, backward and give a few taps at the end to dislodge air bubbles. This way, all of the developer leaves the film and is replaced in a new position. I rotate the tank a quarter turn each time I set it down.

I have never had uneven development of 120 film since I started doing this.

Also, it is a good idea to clean your reels very carefully. Residual photo flow can inhibit development... (although I doubt to the degree we see in these examples).

The cure against uneven devlopment is intensive agitation. The reason for the more darkened edges is that the bromide can easier go away from here. Intensive agitation leads to an exchange of developer everywhere.

That pattern is frequently caused by underdevelopment at the center of the negative from not using enough developer. Try 10 ml per 120 roll and see if it improves.
People starting with film tend to skimp on developer and exposure; both are inexpensive

agitation. kodak's 5 sec every 30 gives me skies much more even around the edges than ilford's 10 sec every 60

PhotoJim said:

Don't do that. Put the soft plastic cap on the lid after you've poured in the developer, rap the tank on the counter firmly to dislodge air bubbles, and then invert once a second until the first minute of development is done. Then let it rest until another minute is up and give it ten agitations in ten seconds (inversion again). Continue doing this once a minute until a minute remains, then begin to pour out the chemistry when about 10-15 seconds remain.

Click to expand...

Well, I've done some testing this weeked and it looks like PhotoJim you were right! I followed the Kodak method for intense agitation and now my negatives are evenly developed. I followed this guide:
http://www.kodak.com/global/en/professional/support/techPubs/f4017/f4017.pdf
The plastic reel spinner handle is in the rubbish bin just so I'm never tempted to use it again. Also ordered a seal kit for the film back anyway as I hear your should do it regulary and I'm not sure of the history of my film back's maintenance.

I've only been into film photography for around a year or so now and I've only ever used Rodinal just because it seemed to damn easy and pretty economical when you're learning. For my testing this weekend though I've tried Ilford ID-11 for the first time and I'm much happier with the results from Tri-x 400. It seems to produce a smoother style of grain.