Shutter speed at 16fps?

[Will Edwards]

Hi all:

Im planning in shooting with the Debrie Parvo “L” camera. I need to know the shutter speed at 16fps in order to meter correctly. I have only been able to find very limited technical information on this camera. Would anyone know anything about this, or have an estimate?

[Phil Connolly]

http://www.cineressources.net/consultationPdf/web/o000/304.pdf

I found this, some info but nothing about shutter speed. The only reference to exposure I found in the document:

"Perfect determination of the diaphragms to be used may be effected by looking at the picture on the film directly through the magnifying glass and progressively closing the iris diaphragm of the lens by means of the diaphragm rod, until the whites and blacks begin to shade off"

So good luck with that. 

It reality it likely to be in the ball park of 160 to 180degrees.  Maybe test with a shutter speed of 1/30 per second and take it from there

[Simon Wyss]

Will, if you would take a photo of the shutter, with a long focal length and as perpendicular as possible to its surface, put it on your computer monitor, zoom a little in, then you could measure the open angle easily with a protractor. As much as I know it seems to be 160 degrees.

[Dom Jaeger]

Yes the shutter is accessible when you lift the front to lace the film in the gate, so you should be able to see the angle of the open sector. Even a rough estimate will do - the difference between say 160 degrees and 150 degrees is 1/36 sec vs about 1/38 sec at 16 fps, which is only a fraction of a stop.

There doesn’t appear to be any mention of the shutter angle in any literature I’ve got or can access on the net, but here’s a still from a film about the manufacture of Parvos that shows the shutter:

Looks to be about 160 degrees, so try 1/36 sec.

[Will Edwards]

I opened up the front, but the shutter is enclosed in it's own "box". 

It is sort of visible if you just remove the lens and look through there, but the widest angle I could get it (it is adjustable via a knob on the front of the camera) where it was still visible and measurable was 85 degrees. 

Since the best estimate of the widest shutter angle is 160 degrees, I'll have to try that and see how it turns out.

According to this website, 160 degrees at 16fps is 1/36. (As has already been pointed out to me, but it still is a useful site)

 

Edited September 22, 2019 by Will Edwards

[Frank Wylie]

No specific shutter speed in this info, but might be useful to you...

 

 

[Mark Dunn]

On 9/21/2019 at 9:17 AM, Phil Connolly said:

"Perfect determination of the diaphragms to be used may be effected by looking at the picture on the film directly through the magnifying glass and progressively closing the iris diaphragm of the lens by means of the diaphragm rod, until the whites and blacks begin to shade off"

 

Ah, the joys of extinction metering. Before even my time.

http://camera-wiki.org/wiki/Exposure_meter#Extinction_meters

But would it work now- can you even see through anti-halation backing?

Edited September 23, 2019 by Mark Dunn

[Frank Wylie]

Everybody did clip tests...