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Re: Query re Primitive Telecine



I asked:
>>I've slung together a primitive setup (five-blade projector + video camera)
>> ... But I'm getting two (2) light green stationary horizontal bars across
the picture:

Stephen Bucksbaum replied:
> ... it's the projector ... you need a modifed belt to adjust for 3/2
pulldown as well >as the 23.97 frame rate ... RCA used to make them several
years ago.

Thank you.  I have one projector for which I'll pursue that option. I
suppose you could use a 3-blade or even a 1-blade shutter if it weren't
driven by the same shaft that drives the claw. It would give you some of the
flexibility of a flying spot.

David Tosh replied:

>It is interesting that the bars are stationary. Does that mean that you
>arranged to lock the shutter speed to the camera video rate? Also ... does
a 5 blade >shutter ... provide a 2.5 rate specific to 24 to 30fps conversion? 

The projector I'm using at the moment (Elmo) has a frequency-controlled
motor --- tweakable, but, once tweaked, stable. So yes, it's synced to the
video frame rate (sorta). I doubt that I could educate you, but: the
five-blade shutter relates to the 24 to 30 (or 23.97 to 29.97?) conversion.
I'll use 24 & 30 for simplcity. This gives 120 images /second, -- - two per
video field. My old and sloppy tube camera (it's haunted) made it difficult
to get exact sync because, in effect, every frame dissolved into the next dozen.

I borrowed a friend's hopelessly automatic ccd camera with "automatic
shutter speed". and got no bars. My own ccd camera has no variable dump,
thus my qestion.
 
Rob said:

># at &*x>!

Sorry, my error: the daemon threw my first attempt back at me and I
corrected it by editing.

Thanks to you all,

                  Ted.
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