" SPEED UP RELEASE" - Hasselblad 500C/CM

Greetings,

Can someone explain in detail the function and operation of what is

known as the "Speed-up Release" button on my 1st - new/used/old

500C/CM .... the owners manual is a little vague as to details of

this feature .... also, is it something you would use for every

shot ??

I would guess that you are referring to the pre-release button. If this is the case then its function is to close the lens shutter, stop down the lens, lift the mirror and open the secondary shutter in the body. The vibration inducing operations are then completed before you make the exposure. Since you can no longer view the image this feature is only really practical if you are using a tripod and photographing pretty much static people/objects. Handheld use really precludes using this feature; but in other circumstances; use it as often as possible.

The "speed up" part of the release cycle allows for a small advantage in reducing the time between pushing of the shutter and recording of the image. Wildi's book claims that the total release cycle on this camera takes about 1/25th of a second. The pre-release completes most of the time consuming activity like mirror swing etc, thus reducing that 1/25th to something less.

It's what everyone else calls a mirror lockup function. While it will reduce the delay between pressing the button and making the exposure; what the use unless you use some sort of sports finder?