Topic: Whites Lines...Don't Do It (to me...please)

[Ed Wenn]

Here's a mystery for you all to ponder. Damion & I took some portraits taken over the weekend with my 5x4 Tachihara and some Type 72 Polaroid sheet film. We got a strange light strip across the middle of each frame. Tried two different 545 holders...same result. What could be causing this? Not noticed this effect with the camera before whilst using a 504 Polaroid back and the smaller size Fuji & Pola instant pack film. Both holders seems to fit snugly enough on the back of the camera.

Also, I didn't notice the effect before whilst shooting sheets from the same pack through my Graph Check sequence camera - although considering all of the visual noise the Graph Check generates it is possible that I missed something. Seems most likely there's a problem with the film, but am keen to see if the rest of you have any thoughts.

[Minutefilm]

Looking at how consistent the position of the fault is I would guess it has to do with the rollers.  When you pull the black envelope the print part remains in it, leaving just the neg part to be exposed.  so the print part is between the rollers at about this position while you are making the exposure.  Did you either - bend the black envelope over (to get it out of the way) or engage the rollers whilst the envelope was out? Either might have an effect on the print...

Ben

[Ed Wenn]

Hi Ben, thanks for the feedback, but I didn't do anything like you suggest. I've been using sheet film for a good few years now and never had results like these. I'll go and shoot one of the sheets in a different camera right now to see what happens.

[Ed Wenn]

OK, so I tired a couple through the Graph Check and got the same results...so that eliminates the camera as the fault point. Someone on Fickle suggested it might be the rollers, but they is kleen. I checked. Think it must be the film.

[gregor]

I get this on certain exposure times (longer exposures in subdued light) using some of my polaroid 52 & 54, on both pinhole & non-pinhole cameras. I  think it's batch specific. It's consistent with March 2007 exp. dates. I keep my rollers quite clean so I don't think that's the issue (for me at least).

Edit: Just checked my cache of sheet film. It's the September 2007 film that I get this from not the March 2007.

[Heather]

did you press in the middle of the pack or something  or bent or put anything on the stack of sheets?
Not sure but whenever I've gotten similar funky on my packfilm it's been due to lightleaks, no matter how well i thought the back was squished onto the camera.

[Stu]

I just can't believe how similar your wife and Damion's wife look.
Uncanny.

[gregor]

Out of curiosity does this happen on all sheets you've shot or seemingly random? On shots where this occurs on my sheet film the dominant light source is to the left or right of the subject.

While I'm careful not to bend the film or press against the emulsion, it's impossible to say how the film was stored by the sellers I've bought from. The only consistency is position of light source & expiration date of the film.

[Ed Wenn]

Hmmph. It looks like this will have to remain a mystery.

My batch has an expiry date of Dec 2005, so that doesn't tie in w/ yours, Gregor.

Heather, ta for the suggestion, but I haven't bent the film in anyway. The sheets arrived sealed in their box too so I can't see how they would have been bent by a previous owner.

Rollers are clean.

Exact same light area with different 545 backs and different cameras....and different photographers for that matter.

I've used sheet film with the same back and one of the same cameras for years now and never had this characteristic, so I don't think it's a light leak - although that's a decent shout.

Suspect it's the film.

Stu.....get your coat!
 

[original_ann]

Ed!

It's got to be the film, I've experienced the EXACT SAME THING on some of my T52 and T54.  I have 3 pola backs - it's not specific to a back.   I've always wondered about this myself but don't have any answers.

[original_ann]

Love the polas, by the way!

[Ed Wenn]

Thanks, Ann. It's not like I'm going to throw the rest of the pack away or anything is it, but it's good to have someone who's experienced the same irritation. Only 8 more from this pack left and then another 20 in my FINAL PACK OF POLAROID 5X4 SHEET FILM....EVER. Sniff.

 

[Skorj]

Gamma rays. Or, simply the results of mis-spreading from old film. Not look like rollers (as the position, or density I would expect to vary), but just aged film... 

[Ed Wenn]

Skorj has spoken (ta). Matter closed. Fingers crossed the final pack isn't similarly afflicted.

 

[Francois]

Gamma rays.

You could always either make a "center line filter" using the laser copier and acetate to even out the exposure... or go to a place where they have an x-ray machine and ask them to "even out" the exposure

[BVStaples]

I had the same issue with a few boxes of expired Type 72 that I used. My was from 2002. I suspect either something laid across the film packs as some time, or some other pressure/time combination is to blame. My holder is OK as it processes my Type 55 sheets with no issues of roller pressure.

Brian