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Old 06-05-2018, 12:24 PM
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Join Date: Jul 2004
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Quote:
Originally Posted by etype2 View Post
Something bothering me. I have an image on freeze frame. I take multiple shots until I eliminate the annoying yellow band. While doing this, the color balance seems to change with every shot. This was also happening with cell phone shots. Makes me lose confidence in my camera. While it’s not a $4K camera, it’s a decent pro-sumer camera. It’s probably the camera operator not understanding his camera?
This may be due to the electronic shutter on your camera. The cell phone is probably a hopeless case if it doesn't give you full manual control.

Does the problem on the Sony appear when you have the shutter speed set manually to 1/30, or is the camera possibly setting a different shutter speed?

The light from the CRT scanning spot is brightest for only a few microseconds, but then trails off at different rates for the three primary colors. The only way to get the same exposure for all three colors everywhere on the screen is to have the shutter open for exactly an integer number of frames of 1/30 second each. If your shutter captures some number of frames plus or minus a fraction, you will see the different trail off of light output from each phosphor color.

Edit: in a camera with a physical shutter, this effect is so abrupt that it will cause a dark "shutter bar" across the part of the picture that didn't get a full frame of exposure.
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