White baton on black background at DVinfo.net

Glen Irvine · October 29th, 2004, 05:14 PM

Dear Folks,

Here is one for someone far more wise than I. I am doing a DVD for a conducting professor at one of the local universities. This involves close-up
(torso) shooting of his thin white baton moving through space quite rapidly
against his black shirt. When setting up and doing some intial shooting
I noticed the baton seems to break into a couple of images ( the image of the
baton and a bit of a second or blurred image as the baton moves through
space ). As I increased shutter speed the effect became far more pronounced.
I'm shooting with anXL1s so I settled on a shutter speed of 60 with a relatively
open iris. I shot in frame mode, but I also checked it out interlaced; there
was no noticeable difference. I've achieved the best image I can in camera
( I think ), and it is suitable but, I'm trying to tweak it in post to eliminate
the baton delay ( I'm sure there is a technical name for what I'm experiencing
but I don't know what that is )......so here are the questions: what am
I experiencing, and are there any suggestions for messing with this in post.
I'm editing on Final Cut 4. I need to retain as much of the clarity of the baton against the black background as possible as this is imperative from an instructional point of view. Any help or comments would be welcome.
Thanks, Glen

Mike Rehmus · October 29th, 2004, 05:51 PM

This sounds like the 'rubber table leg' problem that I just read about.

The camera is really snapping the entire visual field (the frame) of video at once and then reading the captured image off the CCD in raster fashion. Not like the older tube cameras that really read the visual field in a raster fashion.

This makes moving objects like the baton and table legs appear to be fractured (IIRC what the article said). Nothing to be done I think. But then again, I'm not certain that this is the cause of the phenomenon you are experiencing.

October 29th, 2004, 05:14 PM	#1
Glen Irvine Regular Crew Join Date: Mar 2002 Posts: 36	White baton on black background Dear Folks, Here is one for someone far more wise than I. I am doing a DVD for a conducting professor at one of the local universities. This involves close-up (torso) shooting of his thin white baton moving through space quite rapidly against his black shirt. When setting up and doing some intial shooting I noticed the baton seems to break into a couple of images ( the image of the baton and a bit of a second or blurred image as the baton moves through space ). As I increased shutter speed the effect became far more pronounced. I'm shooting with anXL1s so I settled on a shutter speed of 60 with a relatively open iris. I shot in frame mode, but I also checked it out interlaced; there was no noticeable difference. I've achieved the best image I can in camera ( I think ), and it is suitable but, I'm trying to tweak it in post to eliminate the baton delay ( I'm sure there is a technical name for what I'm experiencing but I don't know what that is )......so here are the questions: what am I experiencing, and are there any suggestions for messing with this in post. I'm editing on Final Cut 4. I need to retain as much of the clarity of the baton against the black background as possible as this is imperative from an instructional point of view. Any help or comments would be welcome. Thanks, Glen

October 29th, 2004, 05:51 PM	#2
Mike Rehmus Wrangler Join Date: May 2002 Location: Vallejo, California Posts: 4,049	This sounds like the 'rubber table leg' problem that I just read about. The camera is really snapping the entire visual field (the frame) of video at once and then reading the captured image off the CCD in raster fashion. Not like the older tube cameras that really read the visual field in a raster fashion. This makes moving objects like the baton and table legs appear to be fractured (IIRC what the article said). Nothing to be done I think. But then again, I'm not certain that this is the cause of the phenomenon you are experiencing. __________________ Mike Rehmus Hey, I can see the carrot at the end of the tunnel!