Excerpted from the Phase One XF user guide, a piece of the section describing how to use the digital back with a Cambo technical camera [I believe this quote constitutes fair use; I certainly intend no infringement of copyright]:
Using the two-shot release procedure
Make sure that the shutter is open by using the Preview Lever (1) on the lens. The shutter is open when the red dot is visible.
Enter Live View in the IQ3 Digital Back by tapping on the contextual menu icon (A) on the Rear Touch Screen, then press the Live View icon (B).
Make any desired adjustments to Tilt, Shift and Swing on the Cambo Technical Camera.
Adjust focus (2). If you want to review the depth of eld, remember to close the aperture down to the desired working value with the Aperture Selector (3) on the lens.
Exit Live View on the Digital Back.
Adjust the aperture with the Aperture Selector (3) on the lens, if needed. Adjust the shutter time with the Shutter Speed Selector (4).
The ISO value is adjusted on the IQ Digital Back by pressing ISO on the home screen.
Close the shutter with the Preview Level (1), so the red dot is hidden.
Spring-load the mechanical shutter by using the Shutter Cocking Lever (5) on the lens.
Push the button (6) on the Wake-Up cable to alert the IQ Digital Back to get the sensor ready for the capture, then slowly trigger the mechanical shutter via the shutter release cable.
If the time span between pushing the Wake-Up button and the shutter release is more than four seconds, the capture will be abandoned and the IQ Digital Back will give you the error “Delay between TwoShot Pulses too long, should be max. 4 sec.”
Remember that you need to spring-load the shutter again by using the Shutter Cocking Lever (5) before every new capture.
If you have an automatic two-shot solution, like that one shown in the image on the left, you do not need to wake up the sensor as as the integrated cable solution will facilitate this action. Using an automatic two-shot solution therefore allows you to disregard the “Wake-Up” step above.
The automatic two-shot solution is designed to wake the digital back sensor automatically as you start to press the shutter release and then capture the image when the shutter release is fully pressed. It is recommended to trigger the shutter release slowly to give the digital back a bit of time to wake the sensor.
Um, yeah, that's what it's like shooting a modern digital back on a technical camera. I use a Cambo, one of them a model WRS-1600 just like in the photo, so this is directly applicable to my shooting. If you know tech cameras, you might have heard of Alpa, or Arca, or Toyo or Horseman. In this context, they are more similar than different. A technical camera is essentially a slab of metal or wood, with a place to put a lens and a place for a film holder or digital back. Sometimes, the technical camera body affords options like shift, tilt, and swing. A given lens may also incorporate tilt and swing. These are all features that give the photographer greater control over image characteristics like perspective and focus plane.
Although one can shortcut some of the above steps, and use the electronic shutter on the back rather than the mechanical shutter in the lens, it's still a fairly deliberative process. You've probably been somewhere taking pictures of a beautiful scene and heard someone madly firing away on their DSLR or P&S—though maybe you couldn't hear it due to the silence of mirrorless cameras—and thought they were sure to get the picture they wanted. The techniques is called "spray-and pray" [another shooting analogue], but all it does is give you hundreds or even thousands of images to wade through. In the old days of very expensive film, and before LCD screens and instant histograms, we had to wait to get film developed to see if we had hit the mark. Now, images are almost zero cost; in fact, the more you shoot, the better the ROI on your investment. And, with LCD image review, we can see instantly if we came close to what we wanted. But more images doesn't always equal better images, let alone the right image [except perhaps in sports, wildlife, maybe weddings, and child play photography, where all those images can increase your odds].
In landscape photography, in particular, taking more images may actually reduce your odds of getting the shot you want. Consider that, if you have a good DSLR or mirrorless camera, and good light that presents a scene where you can fire off a fast shutter speed several times a second, you might be able to shoot at 1/1000 and 10fps. You've still missed 900/1000 or 90% of that second. As I've blogged previously, I like to capture more time in a single shot; those blazing fast shutters and hundreds of images per minute don't do me any good, though the technology that makes them possible helps us all. But if you're looking for that special moment, I have come to believe that planning for it [see my post on tools I use], scouting it, returning for it, waiting for it, and then capturing it with a single shot rather than hundreds of frames that each lack the soul of creativity, is much more challenging while incredibly more rewarding. This shot is such an example: Two other shots led to this one over the course of about 15-20 minutes. Between correcting the wrong shutter speed for this particular water flow and waiting for the sun to clear the second bank of clouds, this was a matter of aiming for the image, not hoping the camera was lucky enough to snag it.
I bought my first technical camera last fall. Since that time, I have learned more about light and motion than I had in the previous 50 years of taking pictures. And I learned it by being forced to take my time, by attending professional workshops and learning from people who have forgotten more than I will ever know, and by realizing that one good shot, or a handful of potentially good shots, is a lot more valuable to me than hundreds of acceptable shots that only collect pixel dust.