The reason I asked is that simply working out that 10x8 has twice the linear dimensions of 5x4 therefore should allow a print twice the size never seems to work in practice and has not done so when moving from MF up to LF in my opinion. I was concerned that the 5x7 is not that much bigger than 5x4 and I want an appreciable difference. I agree with 5x4 starting to lose it at 20x16, but on the other hand it can look incredibly impressive if the subject suits it (lots if detail meaning there are no large areas of contiuous tone). From what has been said so far it looks like 5x7 is worth the kit re-shuffle, relagating the 5x4 to far flung places with ready/quickload to keep weight down. I normally end up cropping 5x4 to reduce its stubbiness, so will probably end up with twice the useable neg area on 5x7, which will be cropped very little in most instances. Problem with uncropped stubby 5x4 being that in landscape format, once framed with a thicker bottom edge to the mount than the top and sides results in a close to square frame which tends to lack elegance in my opinion. I do not often shoot colour, but 5x4 seems to be able to produce much larger acceptable colour prints than B&W. Once the 10x8 is up and running I will try contact printing, but still find that 10x8 is a little on the small side for an image. I can see why there is a market for 12x20s out there and have considered it myself, but for now it is not really feasible (not enough cash for camera, lenses and mandatory mule). I do not print large for tha sake of it, but get frustraed when an image wants to be large and I run out of quality !
Thanks for your help,