Colour changes

[Renton Maclachlan]

I'm doing a major production (for me) which involves filming with four cameras which are all effectively the same...though obviously from different angles. I've locked the focus and aperture down etc but I've come across an interesting thing, which I'll show by the two photos below. They are screen shots from video from the same camera, with lights etc all identical. Yet one video is considerablly more golden/brighter (right image - as though you can't tell!) and is out of sync with all the other videos from all the other cameras - and with video from the same camera from other film sessions (left image). I don't know why there is a difference with this one camera during this one filming session, But I would like to bring the odd video in line with all the others colour wise. It seems to be a 'global' difference.

Any suggestions on how to go about this? I'm using Vegas 10 Pro

Thanks

Renton

[Leslie Wand]

which cameras to start with?

you locked focus / aper. but did you white balance them all - and prior to that made sure none of the 'internal' camera settings were on (eg. saturation, knee, etc.,)

[David Jimerson]

Looks like automatic white balance at play.

[Renton Maclachlan]

If it is auto white balance, I could only be that I may have switched this camera on before the green screen lights - though I don't think I did that. Otherwise there is no reason for any difference in the white balance as everything is identical between shoots. AWB in such situations shouldn't change - should it?

If it is a WB issue, is there any way to globally adjust WB to bring the clips into line colour wise?

[David Jimerson]

Well, it was simply an observation based on what it looks like based on what I've seen auto WB do in similar situations.

But whether it's a WB issue or not, the footage is what it is once it's been shot, so there's no special fix based on WB.

A general WB adjustment in the color correcter has to do with the eyedropper buttons to the lower left of each color wheel. Start with the wheel on the right, click on the eyedropper button, click on something that's supposed to be bright white. Go to the middle wheel, click on the eyedropper, and then click on something that's supposed to be medium white or nearto. Go to the wheel on the left, click on the eyedropper, and then click on something black.

This doesn't mean it will match the other footage, though; chances are some tweaking of all the footage will be necessary, and *exact* matches between clips may not happen.

And if this is going to be chromakey footage, I'd work on the color matching *after* you pull the key.

[Don Bloom]

AWB can change for too many reasons to list, that's why it's always best to manually WB however the real question is can it be fixed? The answer is yes. Vegas has some of the best CC tools around.
Set both clips on the timeline, take a snapshot of the good one, (not a freeze frame, a snapshot to the clip board) move the cursor to the one you want to fix, split the preview screen (icon over the preview screen) open up the CC FX and have at it. I'll try to get you some settings shortly, I'm rendering a peice right now but the fact is it can be done.

[Renton Maclachlan]

Thanks so much guys.

It is sooo long since I did white balance or exposure adjustments that I have forgotten how to do them!!!

I remembered seeing a thread/comments/recommendation about a plugin from:

FBmn Software - White Balance plug-in for Sony Vegas Pro 10

...so am checking them out...

Will look at it all tonight...

[Don Bloom]

Here's some info-Hope it helps

[Kevin Lewis]

Great job Don, they look identical!

[Don Bloom]

Thanks but actually the gamma of the lower one could stand to be dropped a tiny bit but I'm just being super critical and the image is still a tiny touch off but frankly for 2 minutes spent on it I'm pretty happy with it.
Thanks for the kind words

[Renton Maclachlan]

Thanks so much Don, Much appreciated.

I haven't had time to do it yet - hardly sat down at the computer yesterday...

One thought I had is that while the brighter image was out of sync with all the others, it seemed to have more...hmmm...'vibracy' than others and have wondered about tweaking the others, even though they look quite good. I guess there is no requirement to simply use the images as they come off the camera. Will give it some thought.

Thanks again...

[Peter Riding]

Sony did a great color correction webinar today. Obviously its too late to watch it live now but they do upload their webinars about two weeks afterwards. Bookmark this page and watch out for it:

Sony Creative Software - Training and Support

You could balance the rogue footage quite easily using a combination of the Color Corrector Filter and split screen (to compare one with another) whilst dipping into the Video Scopes. Don't worry its much easier than it sounds :-)

Pete

[Eric Olson]

As a note for the future, automatic white balance is dangerous for green screen and worse for blue screen.

[Adam Stanislav]

Originally Posted by Peter Riding

Obviously its too late to watch it live now

I wonder what their policy is on people who watched and recorded it sharing it with people who missed it.

It was a great webinar. I knew most of what it said, but I finally learned what the Secondary Color Correction filter does. Very useful, and I have been missing on something like that while it has been there already!

[Chris Barcellos]

They will be posting the Webinar on their sites as they have others. He mentioned it in the Webinar. It was a good primer on color correction techniques, and the explanation of the Secondary Color Corrector helped a lot. I notice he goes to brightness and contrast as his first correction. I like to go right to Levels, which I think give you more control over adjustment.