vertical smear at DVinfo.net

Riley Harmon · April 3rd, 2004, 11:08 PM

is there a filter that can help cut a lil of the vertical smear casued by many camcorders? post your tips/opinions/ideas

Mike Rehmus · April 4th, 2004, 12:17 AM

No, it is a phenomenon of certain types of CCDs and there is no cure except changing cameras.

Alex Taylor · April 4th, 2004, 12:45 PM

Is this not caused by too hot a light source?

Mike Rehmus · April 5th, 2004, 12:15 AM

Yes it is. Too hot for the aperature/speed/gain settings of the camcorder.

What happens is that the charge is bled off of the CCD pixel so much so that the charge dissapation spreads to the readout circuitry and even adjacent pixels, depending on the degree of discharge. Note that this is sort of an operative description and not a complete technical truth.

Shawn Mielke · April 5th, 2004, 12:24 PM

I shoot with the PDX10, rather known for it's strengths as well as it's weaknesses, one of the latter being vertical smear. In an effort to avoid provoking this smear, I try to avoid strong light sources, both in frame and even above frame, where the smear can still streak down into the picture, though the source isn't exactly visible.
Problem sources encountered thus far:

headlights
streetlights
candles
chandelier lights
stadium lights

Finding out ahead of time whether there are problem lights on uncontrollable locations is a good step towards avoiding smear. Non critical time spent with your camera out in the world will add to this specific type of safety instinct.
If you can't test for this beforehand, try to frame your shots in ways that avoid these sources,. My best and only advice.

April 3rd, 2004, 11:08 PM	#1
Riley Harmon Major Player Join Date: Jul 2003 Location: Oklahoma Posts: 424	vertical smear is there a filter that can help cut a lil of the vertical smear casued by many camcorders? post your tips/opinions/ideas

April 4th, 2004, 12:17 AM	#2
Mike Rehmus Wrangler Join Date: May 2002 Location: Vallejo, California Posts: 4,049	No, it is a phenomenon of certain types of CCDs and there is no cure except changing cameras. __________________ Mike Rehmus Hey, I can see the carrot at the end of the tunnel!

April 4th, 2004, 12:45 PM	#3
Alex Taylor Major Player Join Date: Dec 2002 Location: Vancouver, BC Posts: 390	Is this not caused by too hot a light source? __________________ alextaylor.org

April 5th, 2004, 12:15 AM	#4
Mike Rehmus Wrangler Join Date: May 2002 Location: Vallejo, California Posts: 4,049	Yes it is. Too hot for the aperature/speed/gain settings of the camcorder. What happens is that the charge is bled off of the CCD pixel so much so that the charge dissapation spreads to the readout circuitry and even adjacent pixels, depending on the degree of discharge. Note that this is sort of an operative description and not a complete technical truth. __________________ Mike Rehmus Hey, I can see the carrot at the end of the tunnel!

April 5th, 2004, 12:24 PM	#5
Shawn Mielke Major Player Join Date: Jul 2003 Location: Santa Rosa, California Posts: 745	I shoot with the PDX10, rather known for it's strengths as well as it's weaknesses, one of the latter being vertical smear. In an effort to avoid provoking this smear, I try to avoid strong light sources, both in frame and even above frame, where the smear can still streak down into the picture, though the source isn't exactly visible. Problem sources encountered thus far: headlights streetlights candles chandelier lights stadium lights Finding out ahead of time whether there are problem lights on uncontrollable locations is a good step towards avoiding smear. Non critical time spent with your camera out in the world will add to this specific type of safety instinct. If you can't test for this beforehand, try to frame your shots in ways that avoid these sources,. My best and only advice. __________________ Breakthrough In Grey Room