Fellow travellers,
As some of you know, I am a firm believer that the Alpa system is the best all-round solution for landscape and architecture. I've made many posts here and elsewhere to this effect.
As I am a Phase One user and none of my friends who use Hasselblad have the external power supply necessary to test with my cameras, I could not express an informed opinion here.
Whilst there have been a few posts that have been helpful here, in particular from the ever-helpful Doug Peterson, the OP's question hasn't really been dealt with.
So, I did the next-best thing - I got in touch with some dear friends, Thomas and Ursula Capaul, who, apart from being fabulous hosts, also happen to be the owners of a small company in Zurich called ALPA. They've read this thread and know of a customer of theirs who has tried this HD/Alpa combo.
Below is a summary of what they had to say.
So far they had only one customer trying his back on a technical camera. Unless later soft-/firmware improves, their verdict so far: DISASTROUS! Even Rodenstock lenses without shifts produced...
a) a very strong color cast in general
b) a nasty shift to magenta (left and right!) that is persistent, especially in the shadows
c) strange noise artefacts in shadows
d) horizontal line artefacts
In fairness, this was based on only a single copy of this type of back but they ask us to be very careful in recommending such a combo. (I guess this is similar to Phase One's position on the P30+ on technical cameras)
If anyone has had better results, they would LOVE to hear about it, as I'm sure would all the Hasselblad users here. Alpa would, I'm sure, be only too happy to be able to sell their awesome cameras to Hasselblad users, but only if the results are worthwhile.
My friend Tareq has a HD60, so perhaps when we can find a way to power the back, we can run some tests with it on my ALPA STC. The comments above are, BTW, specific to the 40MP.
I hope this helps advance the discussion.
Note that the comments from ALPA would be relevant to ANY brand of technical camera as the problems outlined are the product of how the sensor behaves in response to light delivered through technical camera lenses, regardless of manufacturor. The camera itself is not a factor.
Cheers,