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Sony ENG / EFP Shoulder Mounts
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Old August 21st, 2008, 02:35 AM   #1
Taken away too young... rest in peace Eugene
 
Join Date: Mar 2008
Location: Albany, NY
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Flash makes green smear

Shooting a wedding with my F335 in a dark church. Gain is at +9dB with Low Noise 1 engaged, DCC+ engaged, HD 60i.

I happened to get the photographer taking a shot right up the aisle toward me.

As you can see in the picture, I got this interesting green smear I guess I'd call it.

Is this normal? Is this a function of the CCDs or the MPEG-2 compression?

The frame grab is from Vegas Pro 8, but I looked at the clip in Sony's XDCAM Viewer and saw the same thing. I'm thinking this is only one field, because in the XDCAM Viewer I only see this IF I am frame by frame moving backwards, while when I move forward frame by frame instead of this, I see an expected overexposing flash over the whole picture. The next frame looks correct, but with the white balance skewed too warm, the next frame after that looks correct but with the white balanced skewed too cool, and then the next frame on is correct.

This is thankfully rather invisible in normal playback, but I haven't seen this in my years with my DSR-300A, so I'm wondering what it is.

Thanks.
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Old August 21st, 2008, 03:06 AM   #2
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Ive shot roughly 18 weddings with f330 now (at least the footage in / out the church), with hundreds of flash lights, and I ve never seen something like that in my footage.

Id assume there is something wrong with the clip - try to find that frame on the camera and play it from there - I dont think this is the cams original picture.

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Old August 21st, 2008, 12:18 PM   #3
Taken away too young... rest in peace Eugene
 
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I just confirmed it with in-camera playback as well, it is in the clip.

I talked to someone else about it, and they believe it to be a YUV error from a data value of 0. They suggested a filter or post process screwed it up causing a condition of data overload. And the only filter or post process on this clip was in-camera.

They further added that the white balance bounce confirms that something internal messed with the video and it tried to compensate with the white balance having to radically change and bounce as it stabilized.

I'm thinking it may be because the Low Noise filter doesn't expect to ever see something that bright. But that's just a guess.

Uli, do you have the Low Noise filter turned on during your weddings?

I'm hoping not to see this in the rest of the wedding, but then again I normally try to avoid pointing right at a flash anyway. And as I said, in normal speed playback, it's really not noticable.

Also note that this was only with the high powered professional photographer's flash pointing right at me, the "normal" flashes going off not pointing right at me did not cause this.
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Old August 22nd, 2008, 01:23 AM   #4
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Euegene, you are right - I usually dont have flashes pointing directly to me.

Yes , usually NR1 is engaged.

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