TLR with continuously variable shutter speed?

Recently, Matthew Winn posted:

On Mon, 28 May 2007 19:19:03 GMT, "Neil Gould"
wrote:

My curiosity has been aroused, so I got the camera out and tried a
simple test. I set the shutter speed at 1/2, 1, and somewhere in
between the two. After about a half dozen tries on each setting, I
can say with confidence that the shutter is open for 3 different
durations. Whatever that implies.

On some shutters you can get intermediate speeds in some places, but
setting an accurate speed is so hard you may as well not bother.

I agree that such a capability would have little practical use, especially
with a camera intended to be used with the "sunny 16" table on the back.

Here's a Synchro-Compur from a Retina IIa:
http://tinypic.com/view.php?pic=6be0i8h
The shutter was set at 1/10 for the picture. Faster speeds involve
turning the setting ring anticlockwise, slower speeds are clockwise.

[...]

What all this means is that over the range from 1 to 1/10 and from
1/25 to 1/250 you _can_ set intermediate speeds, as you're simply
selecting an intermediate point on the ramps shown to the right and
left of the speed selection pin. However, you cannot do this between
1/10 and 1/25 because it's at this point that the shutter is switching
over between engaging or disengaging the slow speed escapement. Nor
can you select an intermediate speed between 1/250 and 1/500, and
you're likely to wreck your shutter if you try.

Very interesting. The Synchro-Compur on my Rollei behaves exactly as
you've described, above. There is a detent between 1/10 and 1/25 and
between 1/250 and 1/500. Settings between those speeds "snap" to one or
the other speed, whereas the settings between the other speeds are smooth.
Thanks for the information.

Regards,

Neil

Recently, Bob Salomon posted:

"Neil Gould" wrote:

Recently, Bob Salomon posted:

"Neil Gould" wrote:

Recently, posted:

Does anyone know of a TLR with a continuously variable shutter
speed? In other words the shutter will produced speeds in between
the standard ones i.e. 1/60, 1/125, etc.?
Thanks,
Steve

Yes. I have a mid '50s Rolleiflex TLR that has continuously
variable shutter speeds and aperture.


No it doesn't.

Given that I double-checked this on the camera before writing the
reply, perhaps you have some other explanation for the fact that
there are no detents, and that the shutter speed varies with the
setting of the wheel?


Your camera needs a CLA by a competent repair man. Or women. Rollei
TLR's did not have continuously variable shutter speeds.

Matthew Winn's post regarding the shutter's construction resolves the
issue. Shutter speeds other than those specifically indicated are
continuously variable. Even a CLA shouldn't change this behavior.

Neil

"Neil Gould" wrote in message
t...
Recently, Bob Salomon posted:

"Neil Gould" wrote:

Recently, Bob Salomon posted:

"Neil Gould" wrote:

Recently, posted:

Does anyone know of a TLR with a continuously variable shutter
speed? In other words the shutter will produced speeds in between
the standard ones i.e. 1/60, 1/125, etc.?
Thanks,
Steve

Yes. I have a mid '50s Rolleiflex TLR that has continuously
variable shutter speeds and aperture.


No it doesn't.

Given that I double-checked this on the camera before writing the
reply, perhaps you have some other explanation for the fact that
there are no detents, and that the shutter speed varies with the
setting of the wheel?


Your camera needs a CLA by a competent repair man. Or women. Rollei
TLR's did not have continuously variable shutter speeds.

Matthew Winn's post regarding the shutter's construction resolves the
issue. Shutter speeds other than those specifically indicated are
continuously variable. Even a CLA shouldn't change this behavior.

Neil


Technically you are correct. The cam is designed with a series of (for the
lack of a better word) steps.
Between these steps there will be a slope so that speed ring can rotate
smoothly against the escapement from one step to the next smoothly. The
problem is you don't know what the "tween" speed will be. Say between 1/30
and 1/60 will be.

Recently, Michael lakediver.houston.rr.com posted:

"Neil Gould" wrote in message

Matthew Winn's post regarding the shutter's construction resolves the
issue. Shutter speeds other than those specifically indicated are
continuously variable. Even a CLA shouldn't change this behavior.


Technically you are correct. The cam is designed with a series of
(for the lack of a better word) steps.
Between these steps there will be a slope so that speed ring can
rotate smoothly against the escapement from one step to the next
smoothly. The problem is you don't know what the "tween" speed will
be. Say between 1/30 and 1/60 will be.

Technically you are correct. ;-)

However, the worst-case scenario is that the exposure at the chosen
"tween" speed will be off by less than 2/3 stop. More likely, it will be
off by less than 1/2 stop (e.g., if you want to slightly over-expose at
1/60, choose the mid-point between 1/60 and half way to 1/30). If one
needs more accuracy than that, I wouldn't recommend this camera, anyway.

Neil

Recently, Michael lakediver.houston.rr.com posted:

"Neil Gould" wrote:
Recently, Michael lakediver.houston.rr.com posted:

"Neil Gould" wrote in message

Matthew Winn's post regarding the shutter's construction resolves
the issue. Shutter speeds other than those specifically indicated
are continuously variable. Even a CLA shouldn't change this
behavior.


Technically you are correct. The cam is designed with a series of
(for the lack of a better word) steps.
Between these steps there will be a slope so that speed ring can
rotate smoothly against the escapement from one step to the next
smoothly. The problem is you don't know what the "tween" speed will
be. Say between 1/30 and 1/60 will be.

Technically you are correct. ;-)

However, the worst-case scenario is that the exposure at the chosen
"tween" speed will be off by less than 2/3 stop. More likely, it
will be off by less than 1/2 stop (e.g., if you want to slightly
over-expose at 1/60, choose the mid-point between 1/60 and half way
to 1/30). If one needs more accuracy than that, I wouldn't recommend
this camera, anyway.

Without shooting a test there is no way to know how far off the
"tween" speeds will be. I would be surprised if the marked speeds
were close to accurate to begin with..

With a shooting test, one would know where one stands with the marked
*and* "tween" speeds.

The accuracy of the marked speeds applies to all cameras, regardless of
their heritage or age. If they're off, your exposure will be off, but the
relationship between two speeds may remain the same, so that factor can be
safely presumed to be irrelevant in this context.

Neil

"Neil Gould" wrote in message
...
Recently, Michael lakediver.houston.rr.com posted:

"Neil Gould" wrote in message

Matthew Winn's post regarding the shutter's construction resolves the
issue. Shutter speeds other than those specifically indicated are
continuously variable. Even a CLA shouldn't change this behavior.


Technically you are correct. The cam is designed with a series of
(for the lack of a better word) steps.
Between these steps there will be a slope so that speed ring can
rotate smoothly against the escapement from one step to the next
smoothly. The problem is you don't know what the "tween" speed will
be. Say between 1/30 and 1/60 will be.

Technically you are correct. ;-)

However, the worst-case scenario is that the exposure at the chosen
"tween" speed will be off by less than 2/3 stop. More likely, it will be
off by less than 1/2 stop (e.g., if you want to slightly over-expose at
1/60, choose the mid-point between 1/60 and half way to 1/30). If one
needs more accuracy than that, I wouldn't recommend this camera, anyway.

Neil

Without shooting a test there is no way to know how far off the "tween"
speeds will be. I would be surprised if the marked speeds were close to
accurate to begin with..

"Neil Gould" wrote in message
t...
Recently, Michael lakediver.houston.rr.com posted:

"Neil Gould" wrote:
Recently, Michael lakediver.houston.rr.com posted:

"Neil Gould" wrote in message

Matthew Winn's post regarding the shutter's construction resolves
the issue. Shutter speeds other than those specifically indicated
are continuously variable. Even a CLA shouldn't change this
behavior.


Technically you are correct. The cam is designed with a series of
(for the lack of a better word) steps.
Between these steps there will be a slope so that speed ring can
rotate smoothly against the escapement from one step to the next
smoothly. The problem is you don't know what the "tween" speed will
be. Say between 1/30 and 1/60 will be.

Technically you are correct. ;-)

However, the worst-case scenario is that the exposure at the chosen
"tween" speed will be off by less than 2/3 stop. More likely, it
will be off by less than 1/2 stop (e.g., if you want to slightly
over-expose at 1/60, choose the mid-point between 1/60 and half way
to 1/30). If one needs more accuracy than that, I wouldn't recommend
this camera, anyway.

Without shooting a test there is no way to know how far off the
"tween" speeds will be. I would be surprised if the marked speeds
were close to accurate to begin with..

With a shooting test, one would know where one stands with the marked
*and* "tween" speeds.

The accuracy of the marked speeds applies to all cameras, regardless of
their heritage or age. If they're off, your exposure will be off, but the
relationship between two speeds may remain the same, so that factor can be
safely presumed to be irrelevant in this context.

Neil

If the speeds are off due to a dry or dirty escapement then the tween speeds
will not be accurate, that was my point.
Also, the slope between steps may or may not change some depending on the
brand of shutter or in your case, Rollie.

"darkroommike" wrote in message
...
A continuously variable aperture is easy why would you want a variable
shutter of this type--it would not be very repeatable.
darkroommike

It would make flash balancing easier - you set the aperture per the
flash-subject distance and you set the shutter speed according to the
ambient light, given the aperture selected in Step 1.
Steve

Recently, posted:

"darkroommike" wrote in message
...
A continuously variable aperture is easy why would you want a
variable shutter of this type--it would not be very repeatable.
darkroommike

It would make flash balancing easier - you set the aperture per the
flash-subject distance and you set the shutter speed according to the
ambient light, given the aperture selected in Step 1.

Hmm. I don't quite understand your perspective here, Steve. I gather
you're wishing to control fill flash effectively? For conditions other
than shooting in bright sunlight, the trade-off between overblown
highlights and underexposed shadows can be easily controlled by aperture
alone. In bright sunlight, shoot at the ambient light setting, as the
flash is unlikely to overpower the sun (I presume you're not shooting
macro with a TLR).

Neil