Over exposed band when using 405 poloroid holder

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I recently obtained a Polaroid 405 film holder that appears to be in excellent shape. There were no instructions with the holder. The only possible problem I can detect is that one of the rollers does not rotate as freely as the other. Instead of spinning freely, it takes a slight nudging to keep rolling.

I am testing this back with type 679 film packs, which I loaded in daylight. The film sheets sequence just fine, with each pull-tab leader protruding from the rubber light trap. I'm very careful to pull the film through the rollers slowly and carefully. I bought the 679 film packs from a local photo shop two days ago. The film has a use-by date of March 01 which I did not notice until I began problem solving.

My problem is that every exposure results in about a 2 stop, washed-out band across the middle of the print. I've noticed that this is both the same width and position as the pull-tab leader. On the lens side of the negative, I also see this band and it looks like rub marks that are just short of scratches on the surface. This band is also present in the green "mixing tank" that occupies the space between the developer past pods and the film sheet. My bellows is new.

What could be the problem? Also is it safe to open the 405 back with unexposed film in it? I have not done this, but I'm considering it to see if changing the position of the folded leaders makes a difference. Presently the leaders fit in an indentation where the two halves of the 405 back close together.

Thanks much from a newbie!

Michael Bird

-- Michael L. Bird (chanupa@alaska.net), April 21, 2001

Answers

Michael, it sounds to me like you're not pulling the white tab all the way out before you pull the tab connected to the film. In my experience with polaroid holders (mostly with the 545 backs) almost every problem is associated with either dirty rollers, not pulling the film properly, or else just a problem with the film itself. I've had quite a few boxes of Type 55 film that have had faulty sheets. It's not unusual to get a case of film, and by the time you're done with it, actually have enough faulty sheets that you could fill a 20 sheet box...But, you're talking about pack film here. If I were you, I'd go to the Polaroid website & get a version of the instruction manual. They have troubleshooting info there as well as diagrams showing how to remove the rollers to clean them. It's not unusual to have to do this, it's just routine maintenance. No, you can't open the back once the film is in there. I'm having a hard time trying to visualize the "folded leaders" and their position as you have described, but I think you can probably figure it out if you can get a manual. Good luck

-- DK Thompson (kthompson@moh.dcr.state.nc.us), April 23, 2001.

Michael, It sounds as if you need to take the rollers out and clean them with alcohol. A little isopropyl on a paper towel will do wonders to unstick everything. I do this almost regularly in and out of the studio. Cheers

-- Scott Walton (f64sw@hotmail.com), April 23, 2001.

You can take the partially-used film pack out IF you do it in the dark or in a changing bag, and then put it into a lighttight box or bag. The heavy black vinyl bag that paper comes in works very well.

-- Robert Meier (robertmeier@usjet.net), April 29, 2001.

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