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.
Last edited by Struan Gray; 05-09-2008 at 04:07 PM. Click to view previous post history.