Is the 47mm the widest lens, period?

[mdarnton]

As are a couple of other lenses mentioned along the way here, the Fairchild Curtis is a fisheye. If we expand the discussion there, there are lots of possiblities.

[Dan Fromm]

Well, if you want absurdities there's the mythical 23/5 Tropel that covers 120 degrees wide open. If that, illumination wide open goes to 0 at 60 degrees off-axis. There's also the semi-mythical 44/5.6 Super Aviogon that covers 120 degrees wide open and that's a bit more than two stops down at 60 degrees off-axis.

I've never seen the Tropel, did once get to dandle a 44 Super Aviogon lens on my knee.

[koh303]

Just remmebered - it is nor bronica - but Mamiya who made a 37mm super wide for the RZ67 system - this lens easily covers 9X9cm.

[Dan Fromm]

Just remmebered - it is nor bronica - but Mamiya who made a 37mm super wide for the RZ67 system - this lens easily covers 9X9cm.

Have you checked coverage yourself?

I think the idea that lenses for Mamiya RBs have to cover 9x9 is another Internet myth. To cover 6x7, a lens has to cover a 90 mm circle. A nominal 6x7 rectangle (actual size 2.25" x 2.75", around 56 mm x 70 mm) will fit in a 90 mm circle in any orientation. A 90 mm square isn't needed.

[VictoriaPerelet]

....I would really like a 35mm or less lens that covers 6x7 or 6x9 medium format but I have never come across one.

Maybe this ? http://www.largeformatphotography.in...s/LF6x7cm.html

[koh303]

Have you checked coverage yourself?

I think the idea that lenses for Mamiya RBs have to cover 9x9 is another Internet myth. To cover 6x7, a lens has to cover a 90 mm circle. A nominal 6x7 rectangle (actual size 2.25" x 2.75", around 56 mm x 70 mm) will fit in a 90 mm circle in any orientation. A 90 mm square isn't needed.

Well, i shot lots of 6X9 with rb and rz lenses, so i can safely say it covers at least 9X9. Perhaps more, but that would take testing in some self made camera.

[Dan Fromm]

Well, i shot lots of 6X9 with rb and rz lenses, so i can safely say it covers at least 9X9. Perhaps more, but that would take testing in some self made camera.

Arithmetic error. Nominal 6x9's diagonal is 100 mm. 9x9's diagonal is 127 mm.

Or perhaps a conceptual error. The rectangle is inscribed in a circle, the circle isn't inscribed in a square.

[hoffner]

Well, i shot lots of 6X9 with rb and rz lenses, so i can safely say it covers at least 9X9.

A logical error.

[koh303]

A logical error.

I think the logic problem is yours.
The RB and RZ shoot both vertical and horizontal, on the same axis - making the square area the film covers 9X9cm.
While a single orientatiol rectangle of 6X9 might be covered with a smaller image circle, but in order to cover both orientations the image circle needs to cover a square area - and it does.

[hoffner]

You are very much mistaken.
A circle of a 100 mm diameter can cover both horizontally and vertically inserted 6x9 film area. It does not follow logically that the same circle can cover a 9x9 mm film area. Draw such a circle and see for yourself.