Ideas as to what went wrong with this photo?

[stradibarrius]

These were test shots using Fuji FP-3000 instant pak film. as you can see every exposure is cut off as though the dark slide were still in the film holder but I had completely removed it for each shot. I double checked that the film holder was inserted all the way. I even used two different cameras and two lenses.
Any ideas?

[vinny]

Pull the slide and take a look at a sheet with the holder off the camera.

[onnect17]

Pulling the black protector after inserting the pack in the holder could be a little tricky. Perhaps there are some remains inside. Why don't you check the pack in the dark or inside a dark bag?

[Joe Smigiel]

Does the camera have a focal-plane shutter? Which model camera are you using?

I'm wildly guessing that either there is a format mismatch between the back and camera or that a focal-plane shutter is not properly synched with an electronic flash. However, I'm not sure if such comments might be applicable to your setup or even how many medium or large format cameras might utilize a focal-plane shutter.

[vinny]

Pulling the black protector after inserting the pack in the holder could be a little tricky. Perhaps there are some remains inside. Why don't you check the pack in the dark or inside a dark bag?

Tricky, Why? He's already pulled the black sheet.
You'd lose only one exposure and could instantly confirm if something was in the image path.

[Fred L]

what camera was this from ?

[stradibarrius]

2cameras...a Sinar F2 and a Graflex Super Graphic.

[Fred L]

agree with Vinny, waste a sheet, it's the only way to figure this afaik

[onnect17]

Tricky, Why? He's already pulled the black sheet.
You'd lose only one exposure and could instantly confirm if something was in the image path.

More than once I noticed the first tab had some trouble finding the right way out while pulling the black protector sheet. Same with the 185 and 195.

[Deval]

was everything shot with flash? Do you have another holder you can try