Length of bellows for portraiture with a 250mm lens

[ramesesjd]

Hi all,

I'm building a 4x5 camera from Jon Grepstad's plans and I've been reading up on it on these forums and other sites for a couple of months now.

I've bought a 250mm Fujinon W (no idea which of the W's it is) and am planning on using it for portrait work. In designing the bellows for this camera, I'm unsure about how long to make them. I know that the extension needs to be 250mm to focus at infinity, but how much longer than that should the extension be for general portraiture?

All the bellows designs I've seen assume that you know how much extension you want/need, but don't explain how I'd do that. If someone could point me in the right direction, I'd be very grateful!

Thanks and seasons greetings :)
-Rameses

[Jim Noel]

It fully depends on the type of portrait - head, torso or full length.
If your bellows extension is 50% longer than your lens you will have ample bellows draw for any of the above.

[Ken Lee]

You might find this page helpful: Formulae for Bellows Extension and Compensation (http://www.kenleegallery.com/html/tech/bellows.php)

[ramesesjd]

Thanks Ken, that is *exactly* what I was looking for. Not sure why I didn't find it myself, but many thanks for putting that up.

Cheers,
-R

[ramesesjd]

That's good to know, so many thanks for the note, Jim. Part of what I'm looking forward to with LF is exploring different sorts of portraiture.

Cheers,
-R