Color Bars on XLS(1)

[Bill Ravens]

I've been playing with calibrating my DV color balance using a vectorscope and waveform monitor. On one of my cameras, a "cheap" JVC progressive scan cam, the internal color bars always yield the same RGB regardless of the white balance setting. Does anyone know if this is also true of the XL1s? What I have determined is that the XL1s colorbars are pretty near 75% while that darn JVC is WAY off.

By way of processing, I capture the colorbar pattern onto a bitmap, then check the color chroma and luma with Adobe Photoshop. It seems to me the internal color bars aren't much good for calibrating a shoot if they always yield the same numbers regardless of the white balance setting used during exposure. All they seem to do is verify that my capture to HD is not flawed, as I would expect with DV anyway.

I guess it's back to recording the first few frames with an external color bar card.

Bill

[Don Palomaki]

Hmmmm. Bars allow you to calibrate the playback / viewing system to the recorder by recording a standard reference signal. On a properly aligned system recorded bars should always playback the same!

White balance compensates for variations in lighting to ensure white is white, an electronic alternative to the use of color correction filters as is required for film. It should not effect the reference signal.

[Chris Hurd]

Howdy from Texas,

<< It seems to me the internal color bars aren't much good for calibrating a shoot if they always yield the same numbers regardless of the white balance setting used during exposure. >>

Actually, you want it this way... and thankfully, color bars are *always* the same on this camera. If they weren't, you'd have editors tearing out what little hair they have left, every time you bring video in to the editing suite.

Color bars are primarily for post, to insure that monitors are spot on. They're not really intended for the acquisition environment. They're *supposed* to always be the same, no matter what parameters have been adjusted for shooting (white balance, etc.).

[Bill Ravens]

ahhh...I understand, now. well, at least I found out that my jvc progressic scan cam is chronically way too saturated. Thanx for clearing up my q.

Bill