5x7 to 8x10 conversion?

[singram]

I was wondering how difficult it would be to convert a 5x7 camera to an 8x10 camera.

I have a 5x7 Seneca and the opportunity to buy an 8x10 back. It isn't a Seneca, it is a Rochester Optical Empire State back. The back is complete with the swing tilt mechanism, geared drive, back and ground glass spring back.

The bellows are shot on the Seneca, so I would need new bellows anyway. Could I swap out camera backs and order new bellows to use this camera as 8X10?

Reason: I would like to start contact printing 8x10 negatives and this would be a great way to use what I already have and just move up in size. I am also considering buying a complete 8x10 camera but I thought I would ask first.

Thanks,
Steve

 

[mdarnton]

The famous American folk hero lumberjack Paul Bunyan's best friend was his blue ox, Babe, but he also had a dog, Sport. There was a problem, though, and that was that because Paul was a giant, maybe 30 feet tall, his normal-size dog couldn't keep up with him in the woods--Sport could run to keep up, for a while, but always got tired and fell behind. Paul had an idea, though: he started putting Sport's dinner dish under the front of his dresser. Sport had to lower his front end to get to his food, but his back end could stay standing outside. Eventually, after a few months of this, Sport's front legs started getting shorter and shorter, accommodating to make it easier to get to his dinner, but his back legs, not going under the dresser, stayed the same length. The result was that being shorter in front, and higher in the back, Sport was always running downhill, and so he never got tired following Paul through the woods.

One day Sport got cut in half by accident, and put back together wrong. . . but that's another story. . . .

If you put your tall camera back behind your short camera front, you're going to have the equivalent of Sport--a camera that's always looking downhill.

That's aside from the problem of getting everything fit on the same rail and moving, if you want the back to focus, too, and then there's the problem of folding it all up. I wouldn't assume at all that either the respective tracks or gearing, or relative placement of the gear to the rack, have anything in common. It's not all insurmountable, but maybe not as easy as you might initially think.

 

[bdial]

It's possible (just about anything is given enough time and money), but as mdarnton says, not particularly practical. In essence you'll be building a new camera. What I found in working on a couple of 5x7 Koronas is that there is little standardization on these old wooden cameras. If you have good woodworking skills and possibly some machining skills, go for it. Otherwise it will be far easier and possibly cheaper to get a complete 8x10 camera.

 

[singram]

Thanks both of you for your replies!