Bellows flare? (4x5 camera vs 5x7 with 4x5 back)

[axs810]

Sorry if this is a silly question....


Is it true that you can get a slightly contrastier negative from a 5x7 camera with a 4x5 back vs a regular 4x5 camera because of bellows flare? How about a 5x7 camera with 4x5 back vs a 4x5 with a bellow lens shade?

[N Dhananjay]

Can't say I have seen this. I've done 8x10 as well as 5x7, 4x5 and 4x10 on the same 8x10 camera and I certainly can't tell much difference.

I think the argument is that on the smaller camera, some of the extra light (from the larger image circle) bounces off the pleats of the bellows and ends up on the film as non-image forming light (i.e., flare), whereas with the larger camera, some of this extra light goes onto the GG frame where some of it is absorbed, thus resulting in a smaller amount of light being reflected back. In other words, there is a smaller amount of flare light on the film. In the grand scheme of things, this effect is going to be so miniscule that it is going to be swamped by the other uncontrolled/uncontrollable variables in the system.

A well adjusted lens shade is a much better solution and is within one's control.

Cheers, DJ

[IanG]

I've never heard that but the interior of some bellows do age and lose some of their blackening. I've often re-blackend the interior of bellow on cameras I've restored and the effectiveness must be greatly increased. So on balance I'd say sometimes yes.

Ian

[Jason Greenberg Motamedi]

Is it true that you can get a slightly contrastier negative from a 5x7 camera with a 4x5 back vs a regular 4x5 camera because of bellows flare? How about a 5x7 camera with 4x5 back vs a 4x5 with a bellow lens shade?

I read something similar, and looked into it on my cameras (actually I wanted to increase flare in a controllable way, but that is a different story). I never saw a significant difference with 4x5 on a 5x7 camera or 4x5 on a 8x10 camera. That said, all of my cameras have recent bellows, so perhaps this might be better seen with an older camera.

As mentioned by others, to decrease flare a compendium hood works best.