What happens if you use Hasselblad HVD-90x viewfinder on H4/5X w 60/80MP back?

[rogerxnz]

Hasselblad sell three 90º viewfinders for the H4X and the H5X.

The HV 90x for use with film backs.

The HVD 90x for use with digital backs with sensors 36 x 48mm or smaller.

The HVD 90x-II for use with digital backs with larger sensors, such as the 40.2 x 53.7mm sensor in current 60 and 80MP backs.

All the H4X bodies I have seen for sale have the HVD 90x viewfinder for smaller sensors and I want to use the body with an 80MP back.

What is the downside from using the "smaller" HVD 90x viewfinder with an 80MP back?

Will it just mean I will only see the area of a 36 x 48mm sensor or will I be able to see the limits of the 80MP sensor?

Hasselblad also make a range of focusing screens but I have not been able to find a full list. Some screens can have senor limits marked on them.

What would happen if I use the the "smaller" HVD 90x viewfinder with an 80MP back and a screen marked out for the 80MP sensor?

I want to be able to see the limits of the 80MP sensor and ideally avoid the cost of the "correct" HVD 90x-II viewfinder unless there is a good reason to buy it.

I am buying the gear remotely and any assistance would be appreciated.
Roger

[jerome_m]

The HV 90x for use with film backs.

The HVD 90x for use with digital backs with sensors 36 x 48mm or smaller.

The HVD 90x-II for use with digital backs with larger sensors, such as the 40.2 x 53.7mm sensor in current 60 and 80MP backs.

I think that HV stands for film or film size digital and HVD stands for digital. For a 60 or 80 mpix back, you will need an HV model (no D). The changes between the I and II versions concerns some minor differences in the electronics.

Hasselblad also make a range of focusing screens but I have not been able to find a full list. Some screens can have sensor limits marked on them.

Screens exists in 3 versions:
-standard 40x54 film size (you'll need these for the 80 mpix back)
-with an outside ring blackened to the size of the 36x48 digital backs
-with  an outside ring blackened to the size of the 36x48 digital backs and markings for the 33x44 size of the smallest backs (31, 40 and 50c).

You will need to change the screen and viewfinder.