[Leica] Canon 1D X -- the real marker to the end of the mega-pixel wars?

[rgacpa at gmail.com (Robert Adler)]

Hi George,

You don't place the GG on the shimmed back holder. The GG has it's own
holder that fits to the back of the camera just like the DB holder.

It is not easy to focus properly with the GG holder; I primarily use it for
framing and ensuring my polarizing filter is positioned where I want it.

I have a Leica Distometer to find the closest distance when I'm not using
tilt. I did some work to find out what the best f-stop was to use to get the
greatest hyperfocal distance. So at f/11.3 I can get from about 3m to
infinity in focus. If my distometer says the closest object in my frame is
>= 3m, I'm all set. If closer, I can use focus bracketing. This is for the
35mm.

Haven't tested the 80mm yet as I tend to use tilt with it (it is the
shortest lens for which tilt is available on the Alpa system). I need to do
some testing with it not only to get the right hyperfocal distances at the
best f/stop but also to see how I far I can close down to get more of the
Scheimpflug hyperfocal plane in focus.

This digital MF is a whole new ball of wax for most (with tech cams). Great
results (IMO) once you get it all figured out.

Probably much more than you ever wanted to know...
Best,
Bob
On Wed, Oct 19, 2011 at 9:00 AM, George Lottermoser <imagist3 at 
mac.com>wrote:

>
> On Oct 18, 2011, at 11:38 PM, Bob Adler wrote:
>
> > You are correct of course. The holder for my back, on the Alpa system,
> comes with gaskets that are between .01 and .05mm, in .01mm increments. You
> have to calibrate your back, as in this video:
> > http://www.optechsdigital.com/Videos.html
> > Scroll down to the three videos under Shimming the Alpa.
> >
> > So when I did it to my system, .01mm made all the difference. Pretty
> sensitive!
>
> Interesting.
> It's unclear to me where the ground glass comes into play.
> If you've shimmed for the sensor
> and placed the ground glass on that same adapter
> you've also shimmed the ground glass
> (or am I missing something?)
>
> Regards,
> George Lottermoser
> george at imagist.com
> http://www.imagist.com
> http://www.imagist.com/blog
> http://www.linkedin.com/in/imagist
>
>
>
>
>
>
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>



-- 
Bob Adler
Palo Alto, CA
http://www.rgaphoto.com