[Leica] OT - Sony Alpha 7R

[roark.paul at gmail.com (Paul Roark)]

Frank Filippone <red735i at verizon.net> wrote:

> Paul... is this true for all native A7R lenses?  All AF is done at
> aperture?


I only have the 35mm FE, but I suspect it is the same as the others in
terms of how it focuses.


>  Ditto the A7?
>

I assume it is the same, but I don't have one.


>
> Sequence as I understand it then is....
>
> Push button to shoot
> Lens stops down
>

The lens is stopped down all the time.  I suspect this is, in part, to keep
the sensor as cool as possible.  I higher level of light hitting the sensor
probably generates some waste heat that increases image noise.


> AF happens
>

When I push the AF button, looking at the front of the camera, the closed
down iris appears to open about 1/2 stop for the focusing, then closing
back to it's original closed down position -- whatever the camera was set
to.

(I use "manual" exposure mode, but with auto ISO activated.)

Paul
www.PaulRoark.com