Some older leaf shutter RF's had 1/750 and 1/1000 top speeds. The Werra 3 I
have is marked 1/750, and the Yashica 'Lynx 1000' was named for its marked
top speed... The actual was likely somewhat less. Leaf shutters have to move
the leafs out, stop them, then move them back in; all that takes a longer
time so there are some mechanical limits on the fastest speed available.
Some leaf shutter designs used extra-strong springs at the top speed, to get
the leaf mechanism moving faster.
The 1/2000 or 1/4000 etc speeds on focal planes shutters are more likely to
be actually achievable, as they are a function of the curtain speed and the
narrowness of the gap between curtains. Move the curtains faster and keep
the gap narrower and the effective exposure on the film will be less. As the
mechanism doesn't have to stop and reverse direction the parts can move
faster... and electronic controls might allow more precise control of the
release interval between the start of the first curtain's movement and the
start of the second curtain's movement, thus keeping that gap consistently
narrow.
--
Jim Brokaw
OM-'s of all sorts, and no OM-oney...
on 5/20/03 5:17 AM, Bill Pearce at bspearce@xxxxxxxxxxxxx wrote:
> "Has anyone ever seen a leaf shutter rated faster than 1/500th?"
>
> Jaime,
>
> The new AF Hasselblad has top speed of somewhere around 1/800, without
> checking their webwsite. It apparently achieves it. I think the only
> currently available lens is the normal, so we will see what the others do,
> but I expect all lenses will use the same shutter.
>
> I share your skepticism, but perhaps the electronic controls allow a higher
> speed. Then again, I can't believe my OM 4's can get to 1/2000. I'll bet the
> 1/1000 on most horizontal shutters is questionable, as the 1/6000 and 1/8000
> on vertical ones.
>
> Bill Pearce
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