Basically the problem is the very nature of the light changes as clouds go over. It's way more than just a difference in the amount of light and you really cannot correct for this either with exposure in the camera or in post. I'd use a transition rather than a cut to distract the eye, a Flash transition would work.

If you've got a monster budget as the Hollywood types do then you can take along your own Sun, it's amazing what 100KWs of light WAY up in the air can do to defeat natures efforts at ruining a shoot....until it rains :)

Bob.

Probably leave it alone. If the bright footage is too bright (highlights are blown out) there is absolutely nothing you can do -- they're gone. If the dark video is too dark, you may be able to brighten it with color curves.

In the future, you have to set the zebras on your camera and make sure to manually ride the exposure down so they disappear in any highlights you want to keep (specular highlights are OK to blow out). Make sure to go back up when the lighting diminishes. You cannot rely on automatic.

The highs are not blown out, but it does get a dark when the clouds roll in.

In stead of trying to correct the color, I tried applying the levels fx to try to bring up the lows. That seems to help. The color changes slightly, but at least the transition from sun to clouds isn't as extreme.

Does this sound reasonable?

Try these:
apply the Brightness and Contrast filter to the dark footage. Adjust brightness up in .05 increments, followed by adding contrast in the same amount. You can also dim down the sunlit footage using the opposite technique. This will diminish the difference between the two.

Also, try using the Color curves filter on the dark footage. Grab the handle in the lower left corner, extend it out and drag it counterclockwise, raising the curve. Then grab the handle in the upper left, pull it away from the corner and turn it clockwise, raising the curve. Alternatively, add a point at the bottom of the curve, and drag it up along the left wall of the box, raising the curve.

You might try the Color Corrector, playing with the saturation or other tools.

I'd suggest the main idea is to reduce the difference between the two, as opposed to getting the dark footage to look like the light clips.

HTH,
Scott

Really, color curves and keyframing is the way to go. Curves is so powerful and when done right, doesn't look artificial at all. Very easy to do.

...and if you want to go in the other direction, check the preview for the first tutorial on this page.

This tute was written for AE & Particular, but there is a lot that translates to Vegas.

I would caution against using the Brightness and Contrast controls. Except for generating weird effects, they are almost never the correct thing to use for corrections involving exposure (reason: all pixels are affected, resulting in washed out blacks or blown out highlights, depending on which direction you go).

Color Curves is by far the best tool. Use in conjunction with the videoscopes. Read the tutorial mentioned to see how this is done. Levels can work, using a combination of Gamma and then touching up the highlights and shadows so they return to normal levels after the Gamma application. The color corrector also has a gamma control if you prefer to use that.