Is it 12x15" or 12x16" glass plates?

Those old tailboard english made cameras, did they use 12x15 inch plates or 12x16 inch plates? I'm considering buying one that I've found but I can't actually touch it and it has no plate holders. It is being called 12x15 by the owner, but would it be actually a 12x16 inch? Were both sizes made? Would it have used folding bookform holders?
I'd really like to find at least one holder for this camera, then I could maybe make some more or in some way come up with more holders.
Any information regarding the above questions or actual holders would be most appreciated.
thanks,
Robert Newcomb

The plate holders were likely proprietary, so finding one that fits will take some work. I believe the standard size was 12x16, but above 11x14, very little standardization exists, so anything is possible.

My new camera is 12x16, but it is actually 29,3 cm x 39,3 cm. I have seen a few similar cameras but the filmholder are extremly different. There are many outfits for sale, where there are filmholders. I was lucky that there where 3 filmholders.

My holders are English (or at least, they are for a Perken Son and Rayment camera) and have space for 12x15" plates with perhaps a mm or so of wiggle room all round.

European cameras in 30x40 cm size are very close, but 40 cm is more like 16" than 15", so perhaps that's where the confusion comes in.

Finding holders for your particular camera is likely to be a long search, and even once you have them there is no guarantee that they'll accept modern 30x40 cm or 12x15" film as cut by current suppliers.

If you want to use modern film and have no holders at all, your best bet would be to make a whole new back for the camera, and holders which can accomodate imperial and metric films as cut today. On most English-style wooden cameras with the up-and-over ground glass it would be a relatively simple job to fit an entirely new back - on mine the ground glass and back just pops off leaving a 16.5x16.5" hole surrounded by flat wood and velvet light traps.


PS: my holders are bookform holders with captive darkslides. The slides have a louvred section so they can be folded back round the rear of the camera when pulled out to make an exposure.

It will be 12 x 15, which sounds strange until you realise that it is 3 times the size of 4 x 5. I would expect that anything you find in 12 x 16 will actually be for a European 30 x 40cm camera.