Basic Birger questions

[Luis Avila]

Does the Birger Canon mount increase breathing? and does the mount affect crop factor? Plus is there any loss of light associated with Birger. These questions seem pretty basic, but the mount is fairly new to me. Thanks

[ericyoung]

Breathing is a lens property, so the Birger does not affect breathing (image changing size when pulling focus).

Crop factor is a sensor size relative to lens image circle property, so again is not affected by the Birger mount (but it is affected by the Red sensor size - which is smaller than stills photography 35mm frame size).

There is no glass in the Birger mount, so again it does not affect light levels at the focal plane.

[Karl Gustav H.]

I think erik mentioned that breathing compensation may be coming to a future build of the Birger FW.