Mamiya 645 Pro back knob

[Ulophot]

Looking through the manual of said camera, I have come across one thing I had never thought about, and didn't come across another thing that I suddenly wonder about.

A.) For longer-term storage, it says to leave the mirror in "the uncocked position." Does this suggest locking the mirror up? New one on me.

B.) I have never even thought about the large manual film-advance knob on the lower right of the backs. Nowhere even mentioned in the manual, though a bit of it is shown in a drawing on pg 21 pointing to the multi-exposure dial. An emergency advance, perhaps, in case the shutter stops working?

 

[Kirks518]

Point A - for long term storage, the shutter should not be in the cock and ready position. That will leave the mirror in the up position, which I guess relieves the tension on the spring assembly.

In regards to point B; I just looked at pg 21 of the pro, pro-s, and pro-sd manuals. I don't see a film advance knob in the lower right of any of the backs. I also have many pro, pro-s, and pro-sd backs, and don't see a second advance lever. The only advance lever I see is the 'regular' lever.

 

[spijker]

In regards to point B; I just looked at pg 21 of the pro, pro-s, and pro-sd manuals. I don't see a film advance knob in the lower right of any of the backs. I also have many pro, pro-s, and pro-sd backs, and don't see a second advance lever. The only advance lever I see is the 'regular' lever.

It's the 645 Pro, no the RB Pro.

 

[Kirks518]

It's the 645 Pro, no the RB Pro.

OOPS! Nevermind then.... (Sorry)

 

[Ulophot]

Point A - for long term storage, the shutter should not be in the cock and ready position. That will leave the mirror in the up position, which I guess relieves the tension on the spring assembly.

Thank you; that makes sense, I guess. I just find this surprising, since I don't ever recall seeing mention of this for 35 SLRs since I began shooting with them in the late 1960s (and whose manuals I did read), nor do I recall it in any of my readings on medium format, which, admittedly, did not include reading manuals, including the one for my 1990s used-645 purchase. I do recall that a 4x5 with a mirror I once saw left the mirror out of the image path after shutter release, but that was a really big mirror!
Of course, this leaves the question of my memory function unresolved -- or, might we say, my memory suffers from some technical aberration...

 

[MattKing]

B.) I have never even thought about the large manual film-advance knob on the lower right of the backs. Nowhere even mentioned in the manual, though a bit of it is shown in a drawing on pg 21 pointing to the multi-exposure dial. An emergency advance, perhaps, in case the shutter stops working?

As per the manual for the camera's predecessor, the M645 Super:

Film Advancing by Film Advance Knob of the Roll Film Holder
Check that the Dark Slide is completely inserted (light blocked). When the Film Advance Knob @ of the Roll
Film Holder is rotated in the direction of the arrow until it stops, the camera will be ready for the first exposure.
*It should be noted that when the Coupling Pin (refer to the manual for the Roll Film Holder) is depressed
with the finger, the film will not stop at the first frame.

You use this when you have multiple backs and, ideally, an assistant. It allows you to load film into one or more backs ahead of time and advance each of them to the first frame without having to have the backs on the camera body. It's great for weddings.

 

[Ulophot]

As per the manual for the camera's predecessor, the M645 Super:

Film Advancing by Film Advance Knob of the Roll Film Holder
Check that the Dark Slide is completely inserted (light blocked). When the Film Advance Knob @ of the Roll
Film Holder is rotated in the direction of the arrow until it stops, the camera will be ready for the first exposure.
*It should be noted that when the Coupling Pin (refer to the manual for the Roll Film Holder) is depressed
with the finger, the film will not stop at the first frame.

You use this when you have multiple backs and, ideally, an assistant. It allows you to load film into one or more backs ahead of time and advance each of them to the first frame without having to have the backs on the camera body. It's great for weddings.

Aha! A very thoughtful device. If I ever get a second back, perhaps I use the advance. But I'll leave the weddings to someone younger with a better back.
Thanks for the reply!