douglasf13 Offline Upload & Sell: Off
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dcjs wrote:
Forgive the crappy scetch, I hope it just serves it's purpose.
http://i394.photobucket.com/albums/pp26/schraaat/flange_angle.jpg
The left side shows an exit pupil (green aperture) located close to the sensor (blue) with the "cone of light" (cyan) hitting the sensor at the angle a. The light bundle just clears the mount, which is close to the sensor. If you increase the distance of the mount (right/yellow) to the sensor while keeping the diameter constant, you can choose a more telecentric design (exit pupil further away from the sensor) and thus a steeper angle of incidence b, while still clearing the mount. This same cone of light on the right side would not clear the (red) mount on the left side. Conversely, with the exit pupil closer to the sensor and the mount further from the sensor, the mount diameter could be smaller (the theoreticel extreme case would be a mount that is located at the exit pupil and has the diameter of the exit pupil).
That is why I said that the E-mount being tight and close to the sensor is a challenge for lenses that have an exit pupil that is far from the sensor, while (more symmetrical) lenses with an exit pupil close to the sensor are a challenge because of the angle of incidence.
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dcjs, that sketch does a much better job of illustrating what I was trying to explain. Thanks.
I'm wondering exactly how a-mount lenses would even work with an adapter on a FF NEX?? It seems like the e-mount will get in the way of the light ray from the long exit pupils, but it's tough to say without plotting it all out. Do you think there is room for a-mount lens light rays to get around the e-mount? If not, that only leaves Sony with the option of building new FF e-mount lenses, but then they'll have to be more symmetrical, which causes a host of other issues.
For better or worse, I've been saying from the beginning that I think NEX stays aps-c for still cams. If you look at m4/3, EOS M, NEX, etc., all of the mounts are oversized compared to the sensor, and there's a reason for that.
To me, the RX1 signals the difficulties of making a FF NEX mount, rather than indicating that a FF NEX is on the horizon. Of course, I certainly hope I'm wrong.
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