Xpro 1 OVF inaccuracies..

I think the correct description for the Xpro1 OVF is galilean viewfinder camera; the rangefinder is the system you use to focus (like the leica, old contax or voigtlander, etc...). The Xpro1 has not a rangefinder but it has a galilean finder (like the leicas,but they also have a coupled rangefinder to focus).

Whatever you want to define it, the point is, like already explained, you don't see through the lens like in a reflex camera, so the things you see in the OVF are "offset" from the lens axis. In brief, what you are framing is not what the lens is framing: the closer your subject the worst the error, with no error for distant subjects. That's why the XPro1 (but also the leicas and the Contax G) has a parallax compensation system: as you focus closer, the frame box moves down and right, and the focusing point follows the framing lines.

However this is not very accurate, so you'll always have something more/less in your final picture. Even 4 times more expensive Leicas don't allow for accurate framing; it's a problem inherent the galilean finder.

If you want/need an accurate composition buy a reflex (which shows the real perspective from the lens) or use the EVF.

Cheers

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Mr. President, I'm not saying we wouldn't get our hair mussed. But I do say... no more than ten to twenty million killed, tops. Uh... depended on the breaks.