Dan ..
hold on please and correct me if I'm wrong. How mirror up will close the shutter even if its leaf shutter lens? mirror up means firing the camera and light go thru the black box and hits film .. right? and that is exactly the sensor (A7r) needs to see thru the lens. I mean mirror up fuji body will give access to sensor to the lens.
I viewed the video, seems he is not using fuji lenses .. check it out... but as I expected, tilt shift option is super cool here since you'll have giant optical footage out of medium format lenses to narrow sensor size sony has. stitching images would be another cool idea too.
When you are using a digital back or film in a GX680, the lens gets closed after/during the mirror gets flipped up. This is so it remains light-tight pre-exposure. When you initiate the exposure, it triggers the lens to open, starting the exposure.
You would need to put the back(or in this case, the Sony A7) into "bulb" exposure mode, so it is technically "exposing" when the lens is closed(before and after the lens has opened for the duration of the exposure).
Order of operations on how I see it being done, with camera functioning as-designed:
1. Compose in viewfinder(normally), movements, etc.
2. Once composition/focus is locked down, flip up mirror (this will close the lens' shutter)
3. Start "exposure" on Sony A7(using cable release preferably, to not give any potential vibration)
4. Trigger lens/body to open lens and start exposure
5. Once exposure is finished(and lens is closed), end "exposure" on Sony "back"
As you can see, it can be a somewhat complicated affair this way. If you were to simply go with a smaller, more "designed for small format" system like the Cambo Actus, you could potentially save yourself some of the (above) steps. No mirror to flip up, you'd get live-view focusing, your choice of lenses would be much greater, and you'd have a MUCH smaller package to tote around(if you do location work). The GX680 IS a wondeful system, even for digital. However, it is cumbersome and NOT lightweight nor very portable outside of a studio. I've used mine in the field(with film, mind you), and it works extremely well. However, if I were looking for a technical camera "option" for a 35mm sensor system like the Sony or Nikon D8**, I'd be looking at the Actus really hard.
The only thing that(for me) might be somewhat limiting would be the lack of lens extension available.
Because if you leveled the camera you would lose the composition of the shot, i.e. looking down on a square perfume bottle with a moderately wide lens. I often have to spend a lot of time straightening verticals in post so would be ideal to shoot them being able to correct the convergence of the verticals in the first place.
Does anyone know of a more recent camera with all the movements designed for digital?
Check into the Sinar P3-slr. It retains all of the movements(fully geared!) of its precursory brethren(Sinar P line), but is smaller in size(although not Cambo Actus small, nor in the same ballpark price-wise to the Cambo)
http://www.sinar.ch/en/category/products/cameras/p-slr/Cambo also has their (IMO) more "studio oriented" Ultima 35 lineup, which has been around for over a decade:
http://www.cambo.com/html/products_photo/set01/english/internet/item85.htmlhttps://cambouk.wordpress.com/2013/08/28/eduardo-chacon-why-i-invested-in-the-cambo-ultima-35-camera-system/(old article, but shows movements and some techy details):
http://www.shutterbug.com/content/cambos-ultima-35
