Color Problem

TJIsACoolGuy

TJIsACoolGuy

Active member
This has been covered before I believe.......but I couldn't find it. Check out this frame grab.....The red is messed up on the guys shirt...on his back... What am I doing wrong while filming? The way I see it is that there is a whole chip dedicated to red light...why is it doing this??? How should I shoot differently to avoid it and what do I do in vegas to fix it now that it has occured. ??? Anyway any help would be greatly appreciated... There was another guy who figured this out but I did many searches and couldn't find it.
http://img.photobucket.com/albums/v253/ktjinc/badred.bmp
 
Re: Color Problem

Turn the chroma phase down in your scene file. I saved mine at -7 and reds are no longer a problem.
 
Re: Color Problem

ok, well that picture compressed it and you can't see it really....go to this link...it shows it better on his back....http://img.photobucket.com/albums/v253/ktjinc/badred4.bmp how do you fix this in vegas?  And does that chroma phase turning down in the scene file settings fix this particular problem??? Note that this picture is not zoomed in or anything and is creating pixelation...this is truly what the red looks like in the video.... As I said before, I don't understand how a whole chip for red can't take care of this.
 
Re: Color Problem

Vegas has some really advanced tools for color tweaking.

You can isolate the red saturation by using the Color Curves filter, or you can define the specific range of colors with the Secondary Color Corrector by using the eyedropper and dragging over the colors you want to define.

Gary
 
Re: Color Problem

[quote author=TJIsACoolGuy link=board=Vegas;num=1097798281;start=0#3 date=10/14/04 at 22:38:22]ok, well that picture compressed it and you can't see it really....go to this link...it shows it better on his back....http://img.photobucket.com/albums/v253/ktjinc/badred4.bmp how do you fix this in vegas?  And does that chroma phase turning down in the scene file settings fix this particular problem???  Note that this picture is not zoomed in or anything and is creating pixelation...this is truly what the red looks like in the video....  As I said before, I don't understand how a whole chip for red can't take care of this.[/quote]

It's a quirk of the DVX that the reds are a little hot. By turning down the chroma phase and also the chroma level (not by as much), you'll bring the reds under control. Try it.

As for this clip, what Gary mentioned can help tone down the red a little bit, and you can also use the primary three-wheeled Color Correction tool to back the reds down a bit.
 
Re: Color Problem

There is actually a really simple way to get rid of this in Vegas.  I posted about this a few weeks ago, and it is one of the coolest "simple" tools of vegas.  It is called the chroma blur.  You can mess around with the two sliders, the vertical and horizontal, but I think that a horizontal chroma blur of about 3 should get rid of that.  It works really well on reds and blues that are two high in chroma, but it doesn not effect anything else in your composition. This is definatly a DVXusers favorite friend.

Here are some examples

No Chroma Blur:
nochromablur1.jpg

with Chroma Blur:
withchromablur1.jpg


No Chroma Blur:
nochromablur2.jpg


with Chroma Blur:
withchromablur2.jpg
 
Re: Color Problem

I have actually found that color correcting with either the first or secondary color correcter don't seem to do anything to Red/blue "nasty" stuff, for lack of a better term. Even if you completely desaturate your entire scene, places where those red nasty lines poke up will still show up in B&W. I knew that there had to be some way of getting rid of it and the chroma blur turned out the be the only way. Ther is a downside however, with chroma blur applied to your clips, it can take a very long time to render. My advice, only use it where it is needed, don't apply it to the track, just individual clips, but it does need to be added in front of any other color corrections that you do, ie. make sure that it is first, otherwise, it will try and adjust the color corrected footage, and not be as effective. Hope this helps, but it really is a magic tool. The screen grabs above are not really a bad case of the red "nasties" but if you look closely, the fringing that was apparent in the unaltered clip is gone in the chroma blured clip.
 
Re: Color Problem

Scharky . . . I must admit, I don't see a lick of difference between those shots. What should I be looking for?
 
Re: Color Problem

Let me post another more recognizeable grab. But in the meentime, look at the first photo, and her read sweater. IF you look real close you will see color fringing in the red, kind of like vertical scan lines. You will notice in the second image that they are gone. IF you look at the right side of the wedding dress, you will notice very strong chromatic abberation, blue finging. In the frame below it, it has been drastically reduced. Give me a minute and a post a real good one for you.
 
Re: Color Problem

Ok, here we go.
The following image is pretty self explanitory, but to follow the progression, just know that the top left image is the raw, un CC or any effects, including chroma blur.  The bottom right image is the final image.  Just for self preservation, let me just say that the shooting conditons for this concert were the worst imaginable.  Lots of red lights, but not very bright ones, about equal to my living room, and half the band was wearing bright red shirts.  I was shooting at 1/24th wide open, most of the time, and with 6db gain.  Ouch.  The chroma on the camera was all the way down and you can still see the nasty red vertical scan lines.  I hope everyone will be able to see what I am talking about here, it should be a little more obvious.

chromatest.jpg



So as you can see, even with other color corrections, and desaturation, the chromatic abberation is still represented, and is quite ugly. Only taking out the chroma noise first will you see a good final result. In this case I had it as high as it can go, but there is no real visible softening of the rest of the image, it just effects colors that are out of gammut. The rest of the corlors are not touched at all. Again the downside is a longer rendering time, but hey if it looks good who can complain.
 
Re: Color Problem

Great example and these should bene anyone having this issue. I remember you awhile back helping out on this subject and have done so since. :)
 
Re: Color Problem

Sorry, I have been gone this weekend, so I could not reply, but thanks scharky so much!! It works great... I saw your post before on this issue, but I couldn't seem to find it.  Once again the great people on these forums here have definitely helped me out!  Thanks very much.

TJ
 
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