changing shutter speeds, before or after cocking shutter?

[puketronic]

I'm confused because for some cameras it is better to cock the shutter, then change the shutter speed and for other cameras it is better to do the opposite. Is there a generalization for which cameras require cocking the shutter before or after changing the shutter speed? Like leaf shutters, focal plane shutters, etc. Or is it just a case by case basis. I believe that for Kiev's, doing it the wrong way will break your camera but many other cameras it doesn't really matter so much. Not sure what the best practice is... A good rule will be easier, but the particular cameras that I'm concerned about are:

MF:
Bronica SQA
Hasselblad 500CM
Pentacon Six
Rolleiflex C,D,E

35mm:
Leica M
Olympus OM

[Leigh B]

I can't think of any shutter that must be changed in the un-cocked condition.

If you think about it, that would make it impossible to change exposure without exposing a frame.

- Leigh

[dehk]

Case by case basis.

[BradS]

everything I've read, even from manufacturers literature, says that it does not matter for modern shutters. (where modern is taken to mean post 1945 or so).

Certainly, EVERY modern 35mm SLR with a coupled meter MUST allow the shutter speed to be changed when the shutter is cocked.

[BrianShaw]

Not sure what the best practice is... A good rule will be easier...

good rule: If the shutter speed dial turns to another speed when cocked then it is OK. If the shutter speed dial needs to be forced when trying to turn the shutter speed dial, then it is not OK... for whatever reason.

[Slixtiesix]

If I remember correctly, with pre-war(!) Rolleis you had to set the 1/500sec only when the shutter was uncocked.

[R.Gould]

With all older Rolleiflex cameras, that is, those using the Compur shutter, you set the 500 before cocking the shutter, they have a lock on them to prevent you settong he 500 with the shutter cocked, on general terms with the older compur and prontor shutter it is better to change shutter speeds with the shutter uncocked, and with the English Epsilon shutters never ever try and change fro 25 to 15 with a cocked shuter, serious damage can be done to that shutter, with modern electronic shutters such as fitted to the bronica then you must have the shutter cocked at all times so changing speeds with the shutter cocked is not a problem,and I would think that applies to other modern shutters, s to sum up, with German clockwork it is in advisable to change shutter speeds with the shutter cocked, with modern electronic shutters then no problem, at leastwith leaf shutters

[DWThomas]

The Bronica SQ-A has an electronically timed shutter and can be changed any time. I believe some early (pre-WWII) folders had problems with the highest speeds engaging some special mechanism that jammed if moved while cocked. I think Brian Shaw's answer pretty well covers it.

[E. von Hoegh]

If I remember correctly, with pre-war(!) Rolleis you had to set the 1/500sec only when the shutter was uncocked.

That's a feature of the Compur Rapid shutters, also Compur 1 shutters and a few others. Setting the shutter to it's highest speed brought an auxiliary spring into play, setting the speed before cocking the shutter reduced wear. Compound shutters should be set before cocking, regardless of the speed.

[Ian Grant]

Some pre-WWII cameras needed the shutter speed set before it was re-cocked, and I think it's the same with some Russian Leica copies, this is to do with the tensioning of two blinds and consistency of the shutter speeds

It really depends on the camera, for instance with a TP Ruby reflex whenyou cock the shutter that sets the first curtain and tensions the second but you then adjust the shutter speed which sets the sit width between the two curtains.

With many older SLR's ideally you should set the shutter speed first it is possible to damage some shutters making changes after cocking with some models. I just remembered that the shutter speed dial can only be adjusted in one direction on some Russian SLRs as well.

In addition older Compur's can only be set (or unset) to the fastest shutter speed before cocking the shutter and some say shutters should be stored uncocked not that I've ever found it makes a difference.

Ian