If you set your shutter between two speeds do you get the speed in between?

[sully75]

I have a synchro-compur shutter graduated in 1/1, 1/2, 1/5, 1/10, 1/25, 1/50, 1/100, 1/200 and 1/400. My light meter is 1/1, 1/2, 1/4, 1/8, 1/15, 1/30, 1/60, 1/125, 1/250, 1/500.

If I set my shutter between 1/25 and 1/50 sort of closer to the 1/25, am I getting something like 1/30? Or are the speeds discrete? Should I just set it to the next faster speed?

Thanks!
Paul

[Steven Tribe]

Most shutters have distinct changes in speed as the external lever pushes an internal lever system with "shoulders" with "flat" sections between speed changes. I doubt very much that the indicated speeds on your compar are very near all the indicated speeds. The 1/400 is probably nearer 1/250 than 1/500. Unless you are a colour dias person, I don't think the indicated differences will mean much. Isn't it easier to modify the aperture a little?

[Fotoguy20d]

From Carol Miller (Flutot's):

On some shutters (e.g., Ilex, Betax, Alphax, and Compounds) the dial is just a smooth sloping dial—unless someone has adjusted the dial and made bumps or indents to correct the speeds. With these shutters, it's possible to get additional speeds in between the marked speeds. For example, if you set it between 1/5 and 1/10 your speed would be 1/8 in most cases, depending on the slop or if it's been adjusted etc.

With other shutters (e.g., Compur, Rapax, Prontor, Copal, and Seiko) the dial has steps cut into it and if you try to move the dial while cocked you could break the little pin that rides against the speed dial. These type shutters don't allow for much correction if the speeds are off. Since there are only steps, the step you are on is the speed you get.

[sully75]

Ok that settles it. Thanks!

[J. Patric Dahlen]

With the rim-set Compur and early Compur-Rapid you can use intermediate speed settings except between 1/10 and 1/25, and between the fastest and next fastest speed.

With the Synchro-Compur you can't and shouldn't try. Adjust the aperture instead.

[wskmosaic]

Is there an easy explanation for the [B]exception[B]between 1/10 and 1/25?
tnx
Warren

[Peter K]

Is there an easy explanation for the [B]exception[B]between 1/10 and 1/25?

For the slow speeds another clockwork is used. The same for the fastest speed, there is an auxilary spring used to accelerate the shutter.

[wskmosaic]

Sorry to seem persistent, but do slow speeds extend to those below 1/10 as well?
Warren

[Mark Sawyer]

Bear in mind that many shutters, even modern Copal shutters, are often off by half a shutter speed or more, and may change speeds with varying environmental conditions.

[wskmosaic]

For the slow speeds another clockwork is used. The same for the fastest speed, there is an auxilary spring used to accelerate the shutter.

Sorry to seem persistent, but do slow speeds extend to those below 1/10 as well? And does the 1/10-1/15 exception extend there, too?
Warren