I think H3d and my Hasselbald Cf back interface are same.
I'm use many mechnical shutters for my cf digital backs, just connect your shutter and hasselblad back. What is problem, please detail what is problem sync.
I used to think it would be the same, but apparently the H3D series backs have something different in the way they work. It is not just me who has seen this, I ended up contacting the guy who made the article below, because I wanted to know how he get his rz67 to sync.http://probokeh.com/blog/hasselblad-h3d31-vs-mamiya-rz67-pro-ii-h3d31-back/
Turns out, he didn't really get it to sync. He had to use a remote release and set the h3d expose time on the back to 2 seconds, and shoot the rz67 in between. I ended up going a bit further and made my own solution that mainly eliminates that, but it was not easy to figure out.
Alright, as for the problem itself, basically even if I directly sync with a sync cord from the rz67 to the h3d, the exposures will have a horrible purple caste and artifacts at any speed above 1/60th. Interestingly, if there is no ambient light, and you use a strobe, the images turn out perfectly even at 1/400th. This made me believe the h3d backs have a problem with early light, and the low tolerances and timing of the rz67 was too out of sync for it. My solution, was to solder the cable from a rz67 L-grip into a 2.5mm jack and plug it into the triggering port of the h3d. I then took the other end of the cable from the l-grip for the rz67, which is basically an electronic release, and soldered it into a 3.5mm jack and placed it into the flash output port of the h3d. So, now to shoot with the rz67, I press the "shutter" button on the grip, this "triggers" the h3d and it starts exposing, but nothing has happened yet. As soon as it starts exposing, it sends a signal through the flash output port and triggers the rz67 via the electronic release on the other end. The result? Perfect exposures at all shutter speeds now. You can use this to sync perfectly with the Fuji GX680 as well. It seems this only affects h3d backs. I used it with the h3d-39, and the other guy used an h3dii-31, so I think it is safe to say it is a problem with all of them.