Color matching between cameras in Vegas

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dishan

Well-known member
I'm using a T2i and a GH2 for some live event documenting, and having trouble matching the colors in post.
I try pretty hard to get them to match in camera (white balance, etc), and its OK, but because of various discrepancies in picture profiles, etc, the coloring always seems off when I cut from one to the other.

So, I've decided I should shoot some color charts to try and work out a template I can apply to these cameras when used together. But I'm unclear as to the proper workflow to do this kind of thing in Vegas. Are there any tutorials on color matching footage from various cameras in post? I feel like shooting a color chart would be especially helpful, but I'm still not sure exactly how to go about it.
 
I recall seeing a thread about that plugin before (although possibly not on this forum)- the author was asking for beta testers. I was under the impression that it was still under development. Looks like they've actually released it!

I wonder how well this works- I guess I'll need a newer version of Vegas, though. Still using 9 at the moment. Looks like 10 and up only are compatible.

However, I think it would be more helpful to know what the plugin is actually doing in the background. Having a plugin do it for you is nice- knowing and understanding how it works so you can do it yourself (and possibly in other NLEs) is a much more powerful tool.

That being said, maybe someone more proficient in Vegas can help answer the OP's question? My coloring is often down outside of Sony's app, however I understand that their color correction wheels are rather useful if you know what you are doing..
 
Step #1 is to make sure you're using a properly calibrated monitor.
I have an older CRT model JVC in my edit suite that has all the options such as underscan and blue-gun only switch.
I use this tutorial to set it up every day.
If all you have access to is a regular TV set, try this tutorial.
If you don't have either one, consider a tool like the Spyder Elite to calibrate your computer monitor.
After that is done, Glenn Chan has a good camera matching tutorial on his site.
Good luck with getting everything properly set up.

Mike
 
I'm definitely no pro, but one way I like to color match in vegas is to use RGB curves or three individual levels for RGB separately.

So starting from a clean timeline with no vfx applied, put your source/reference clip on one track and your target (to be adjusted) clip on another track.

Use track motion on both tracks so that both clips are visible in the preview window simultaneously. Then adjust their position on the timeline to find a shot with similar content (same subjects, same background, etc). It's also a good idea to choose a shot that is properly exposed and represents the overall contrast well.

The next step is to go to the video fx tab, find "Channel Blend" and drag a "Distribute Red Channel" to the preview window to set it as the Output fx. This will show only the red channel, but in b&w.

Now for curves, you can do it all in one vfx box. So find "Color Curves" in the vfx list and drag in a "Reset to None" preset to your target clip (the one you want to adjust to match the other one). Change the channel in the drop down box of the recently applied curves to "Red" since we're dealing with the red channel, and proceed to adjust the red curve so that the highlights, midtones and shadows match the source frame.

Once you're satisfied with that, move on to the green channel; click on the Video Output FX button on the preview window and change that channel blend that we applied earlier to "Distribute Green Channel". Now go click the vfx button of the target clip to open the previous curves window and switch the drop-down to "Green". Once again, match the highs, mids and shadows. Then repeat this procedure again for blue (channel blend, distribute blue, curves, match highs/mids/shadows)

When you're done, un-check the Channel Blend plug or delete it and if you did a good job, your colors should be fairly close.

For extra assistance, you can use your video scopes to help during the matching process. Also, by cropping in to individual sections of the source and target, you can more easily isolate the areas you're working on to get a better sample size when targeting the highs, mids and shadow areas.

If you don't like using curves, you can achieve similar results by using levels, but for each channel, you'll need to drag in another Levels plug and set it to either Red, Green or Blue depending on what you have your channel blend set to. If the image needs further tweaking, I like to use the free AAV colorlab plugin's 6 vector to adjust rgb/cmy. Placed after the curves/levels in the vfx chain.

If you get results that you're satisfied with, then you can save the vfx chain to later apply to a set of clips or an entire track of clips of footage from that camera. You most likely won't be able to use this one for every scene, but it should work for most clips that are within the same scene.
 
Mike,

Fancy meeting you here! I dialed into this forum 'cuz there was lots of info on my new Panny AC130. Then I saw there was a Vegas sub-forum, and couldn't resist posting.

...Jerry (the other Rodney)

PS: Good advice.
 
Jerry, welcome to the forum!!
I hope you plan to stick around as your web rendering tips will be very useful to a lot of folks on here.

Mike
 
qazwsx said:
Use track motion on both tracks so that both clips are visible in the preview window simultaneously. Then adjust their position on the timeline to find a shot with similar content (same subjects, same background, etc). It's also a good idea to choose a shot that is properly exposed and represents the overall contrast well.
Click to expand...

You already lost me at this part. Track motion? I usually just create a temporary mask on one layer to see half of it live with the one behind it.
I'm not sure my version of Vegas has "track motion".

The next step is to go to the video fx tab, find "Channel Blend" and drag a "Distribute Red Channel" to the preview window to set it as the Output fx. This will show only the red channel, but in b&w.

Now for curves, you can do it all in one vfx box. So find "Color Curves" in the vfx list and drag in a "Reset to None" preset to your target clip (the one you want to adjust to match the other one). Change the channel in the drop down box of the recently applied curves to "Red" since we're dealing with the red channel, and proceed to adjust the red curve so that the highlights, midtones and shadows match the source frame.
Click to expand...

Ok, I've been using vegas since 2001 (back when they were Sonic Foundry), and I must admit that I feel lost trying to follow your instructions! :(

I can apply channel blend and select distribute Red Channel, but I don't know what you are referring to when you say things like "set it as the Output FX". I'm also not familiar with dragging effects onto the clips- I usually right-click a clip and hit either Media FX or Video Event FX, then choose which effects to apply and in what order.
I'm starting to get the feeling that your version of Vegas looks very different from mine (version 9).

I did try to copy this procedure as much as I could regardless. But I feel like I'm missing something- If I apply the channel blend FX to distribute red channel, I get a B&W image of what I assume is the red channel. But if I open the color curves plugin directly after it in the chain, and set the drop down to "Red", I'm adjusting the color on top of the B&W image. Meaning, instead of changing the brightness or contrast of the resulting B&W image, I'm instead seeing the black and white image turn more green or yellow as I adjust the curve (meaning instead of black and white, it will be off-white and yellowish black). I'm not exactly sure how one is supposed to match the mid/high/lows of the other image like this- it doesn't make much sense me. Am I doing this completely wrong?

Maybe the color curves is supposed to go IN FRONT of the channel blend FX in the chain?
 
A mask will work too, but resizing each track using track motion will allow you to see both clips in their entirety side by side simultaneously.

A good way to find out where things are is to leave your mouse pointer over the icon for a second or two — it will reveal a small text box that tells you the name of the function. Also, searching the help index can also assist in locating items you're unfamiliar with.

To access the track motion properties of a track, look on the timeline and to the left of the screen there will be a list of tracks (1, 2, etc) each one has a level slider and some icons. The one for track motion looks like two over-lapping rectangles and one has an arrow inside of it.

Click that, then shrink the box and reposition it. You can also squeeze them down horizontally or vertically by disabling the lock aspect ratio box. If you change your project properties to have double the height or double the width and fit both clips simultaneously without squeezing.

In vegas, you can drag/drop presets (those eyeballs) from the Video FX pane into three different areas:

1) The clip itself - FX applied here only affect the clip

2) The track that the clip resides on - FX applied here affect all clips that reside on that track

3) The preview window (otherwise known as the Output) - FX applied here affect every clip on every track of the project.

Then there is the heirarchy. It goes Output/Preview Window FX -> Track FX -> Clip FX. Think of it like layers or adjustment layers in photoshop where Output is at the top and Clip is at the bottom.


So when you apply the channel blend to the Output, it affects every clip on every track of the project.

And when you apply the levels or curves, you are doing it on either the track or the clip, which are below the Output becasue the channel distribution is just a guide to help you see only the color you are adjusting.

If you only do Red, there's no way it's going to look right. You must do all three RGB because that's what video is made of, RGB pixels. Changing one or two will have a dramatically different effect than changing all three.

What you are doing is basically changing the highs, mids and shadows for Red, Green and Blue independently and once they are all adjusted they get mixed together and should simulate the target you are trying to match, if done properly.
 
Here's a quick video that shows what I am talking about.
http://int.infdv.com/temp/dvxuser/channel-colormatch.mp4

I started with shots of the same subject taken by two different cameras (http://www.careace.net/wp-content/uploads/2010/12/Comparison-Colors.jpg) and cropped them.

I set the project to 2560x 720 (two times wider than 720p) and used track motion to place each shot site by side.

Then, since whoever shot the image didn't properly white balance, I used AAV Colorlab plugin to fix the white balance of both clips. This isn't really a necessary step, but you described in your original post that the cameras were white balanced.

Anyway, to shorten the recording, I had all of the settings for the curves and levels already applied to the clips and I just went back and forth and enabled them in the order I would have done it live, but hopefully you can gather the general idea that I was trying to get across. edit: Forgot to mention that I also did the curves as separate vfx instances in the chain as I thought it might be less confusing to look at.
 
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qazwsx said:
Here's a quick video that shows what I am talking about.
http://int.infdv.com/temp/dvxuser/channel-colormatch.mp4

I started with shots of the same subject taken by two different cameras (http://www.careace.net/wp-content/uploads/2010/12/Comparison-Colors.jpg) and cropped them.

I set the project to 2560x 720 (two times wider than 720p) and used track motion to place each shot site by side.

Then, since whoever shot the image didn't properly white balance, I used AAV Colorlab plugin to fix the white balance of both clips. This isn't really a necessary step, but you described in your original post that the cameras were white balanced.

Anyway, to shorten the recording, I had all of the settings for the curves and levels already applied to the clips and I just went back and forth and enabled them in the order I would have done it live, but hopefully you can gather the general idea that I was trying to get across. edit: Forgot to mention that I also did the curves as separate vfx instances in the chain as I thought it might be less confusing to look at.
Click to expand...

Wow, that was amazing!

Holy smokes, I didn't realize what you meant before, but that makes perfect sense now!!
 
I'm glad it made sense. The sample image I used could have been better though, but I just wanted to show the general process.

After fixing the white balance with colorlab, it really could have been matched by just a little bit of desaturation and another instance of the colorlab to use the 6-vector to adjust the magenta, cyan, yellow and reds. But the other method is more useful when the differences are a little more severe. http://int.infdv.com/temp/dvxuser/colormatchsimple.png
 
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