how set-up and make long exposure at Hasselblad H1 without the lens?

[pan_k]

Hello from Russia!
Dear Hasselblad Support, I have a question:
how I can make long exposure (1-2-3 - any seconds) at Hasselblad H1 camera (by inner camera's shutter)?

Shooting terms are follow:
[Digital Back]+[H1 body]+[CF-adapter]<=[obscura/pinhole]

- I using H1 with Phase One P65+ Digital Back
- I attach CF-adapter
- and insert here the cap-adapter (like V-camera's front cap with CF/V bayonet) + pinhole plate inside.

Next, I use Settings -> Custom options -> Lens exposure lock (No) - to shooting without the lens.

Cocked CF-adpater, and then cam make a shot..
But I can't set-up long exposure that I need (with pinhole)

I want to make photos with H1 using Remote Control and Tripod.

Can You help, how I can set-up and using long exposure at Hasselblad H1 in my situation (without the lens and with attached CF-adapter). May be I need to use additional cords too?

Regards.
Aleksey.