Re: Shooting Smart Slate on EX-1

Well Most CCD cameras have an electronic shutter that allows the CCD to
"Gather Light" on each pixel for a period of time equal to 1/2 the frame
timing (i.e. 1/48th of a second with 180 degree shutter and 23.98fps Frame
rate). However since the shutter is electronic and not necessarily
synchronized with the transition of the LEDs on the Slate it is possible
because of the 3/2 pull down scheme to end up with an exposure of one frame
on video that has the transition of 2 frames on the slate superimposed on
the same pixels. This will make the numbers intermittently un-readable as
some digits are changing while the shutter is open.

In addition to that effect, some prosumer cameras handle variable isa or
variable exposure by simply dynamically varying the shutter speed to allow
enough light to gather on the CCD for proper exposure before the samples are
digitized. This can cause variable motion blur artifacts and variable
artifacts when shooting changing numbers who's transition can happen while
the shutter is open rather than just as the virtual shutter closes.

Doesn't really have much to do with compression as the frames are
reconstructed on playback to represent the signal on the CCD at that instant
in time. Only on fast pans where all pixels in the frame are changing from
frame to frame to you have Block Errors where the compression breaks down
because the bandwidth can't support total Delta-V of all the changing pixels
in the frame.

Clear as Mud right? Perhaps the best explanation for a novice editor is
"Hey Sh*t happens"

----Courtney

"ibirds4" <mattbbryant@xxxxxxxxx> wrote in message
news:75e03080-42b1-4480-a532-69a55f877d0a@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Anyone have experience shooting a smart slate with the EX-1.
Currently the footage has the timecode blurring frames with some
frames clear and others unreadable. Jamming to zeros works and when
frame is clear video and audio sync.

Workflow is 744T at 23.97nd and slate is set to auto sync. Camera is
shooting 1080p/24 and comes into FCP as a 23.97 file.

We're cross jamming another camera and all the numbers show up clear,
they just skip some numbers due to the pull down so it seems the
blurring has something to do with the camera.

Syncing is still easier than using the clap but would really like to
know the cause for this.

Anyone come across this situation and know the answer.

Thanks


.

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