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View Full Version : Need Help Troubleshooting Toyo 6x9 RF Back Mystery



Andre Noble
19-Jan-2005, 19:59
I shot Kodak HIE B&W infrared with#25 red filter with a recently-acquired, but used Toyo 6x9 RF back, and am getting weird problems with my film.

I am getting (light) vertical lines on my HIE negatives where one would expect dark vertical lines if it were a light leak problem.

These light lines are periodic, about 9.5cm apart, in middlish of the 6x9 frames. Again, weird thing is they are 3 to 4mm width lines of lightness.

Admittedly, the light seals of back are tacky and flattened and I will be replacing this weekend.

But my lingering question is this weird problems due to physiacl deformation of the film or do you think it's some weird phenomenon due to a light leak that's the cause?

Thanks for any help.

Andre

Nick_3536
19-Jan-2005, 20:22
Does it only happen with the infrared film? Maybe a spot in the back isn't IR proof? Just a dumb guess.

Andre Noble
19-Jan-2005, 21:19
Yes, it only happened with the one and only roll of kodak Infrared HIE film that I tried recently. I was careful not to remove the dark slide completely from holder. I've previously tested the holder for potential light leak problems with color transparency film by rotating loaded holder in bright sun, but I didn't find any problems.

BTW, the "lightness" lines are not sharp, but somewhat faint and run the complete vertical height of the neg. Finally, the first frame (of 8 total) was normal. All the others were affected.

Oren Grad
19-Jan-2005, 21:20
Andre -

If you look closely at your Toyo 6x9 rollholder you should see that the pressure rails in the film gate - above and below the opening in the back - are notched in several places, all the way through both top and bottom toward both ends of the frame, as well as a partial notch on the bottom at the middle of the frame. Do your lines correspond to the location of any of these notches?

Andre Noble
19-Jan-2005, 21:56
Hi Oren,

No. I was checking into that and the lines don't correspond. In most frames, a single line is visible in almost exact middle of frame. Other frames two lines in a frame at the 1/3 and 2/3 across locations, but this too varies.

BTW, the film is Kodak HIE spooled with Kodak 400 nc color paper backer by David Romano - good stuff (I wish he still spooled the Kodak color infrared EIR 120 as well).

Hey, as I pulled the paper backing from the trash to look at it, I just noticed that it showed vertical kinks at the same intervals as the light marks. (The developed film itself doesn't look kinkedhence I didn't see this earlier)

Perhaps the film is getting kinked as it passes the course of the Toyo rollers due to the holder's design, and this kinking of the film as it sits waiting next exposure hence affects the film's photochemcal response properties? (I do not notice any softening of the image in the lightness area that may indicate the film was kinked at time of exposure, but you never know) and the lightness itself indicates LESS sensivity to development, not more - as one would expect from a light leak.

any thoughts anyone?