Need help with colour correction

smashguy37 wrote on 3/8/2010, 1:07 PM
I'm wondering if it's just me, but I shot something for work yesterday and need some opinions.

http://img121.imageshack.us/i/image1frz.png/
http://img641.imageshack.us/img641/157/image2db.png

Those are two stills from the shoot. How would you guys suggest making the colour a bit more...natural? It's seems slightly green/yellow-ish to me. I can sort of improve it by moving away from those colours in the mids and a tad with the whites, but I'm still not 100% with it. The skin colour always seems too orange/yellow.

This was shot on a Canon XH A1s and I usually manually do a white balance, but this shoot was done on auto. Any suggestions would be greatly appreciated, I can usually adjust to taste but I'm having a hard time with this one, thanks.

Comments

musicvid10 wrote on 3/8/2010, 1:16 PM
Nothing wrong with the color.
In fact, since it was shot in winter, your auto WB shifted just a bit to the blue side in the mids.
I would leave it alone. If it looks yellowish to you, your monitor may be balanced too warm.
smashguy37 wrote on 3/8/2010, 1:36 PM
Okay. I really wish I had proper balance cards sometimes, I feel in the dark sometimes.

If anything it seems green-ish ever so slightly, but maybe it is my monitor. I think I'm just being too nit picky. I'm more used to doing shoots in the summer when everything looks warmer and more saturated.

Thanks.
willqen wrote on 3/8/2010, 3:33 PM
Color looks good on my system also. No problems there that I can see
rs170a wrote on 3/8/2010, 4:00 PM
Make me #3 who says "looks good to me".

Mike
Jay Gladwell wrote on 3/8/2010, 4:12 PM

I'm with MV. It must be your monitor.

They do drift over time. You should recalibrate.


smashguy37 wrote on 3/8/2010, 4:29 PM
When I initially bought my monitor (23" Samsung P2350) the colour was really off but ever since I reinstalled fresh a few months back it's been fine.

I didn't want to bother touching it because I always seem to make it worse when I use the nVidia calibration software, unless there is some good freeware out there, I'll take a crack at it.

I use Cinema Displays at work, so I'll see what it looks like on those later this week. Thanks guys.
Serena wrote on 3/8/2010, 4:39 PM
The colour balance is OK. Suggest you have a look at the clips using "video scopes" because you have super blacks and super whites in those frame grabs. Have a play with Sony colour curves or levels. The 2nd pic has choked up blacks and there is a lot of lost detail in hair, faces and the black tee shirt. There is some detail lost from the whites that can be recovered, but nothing to be done about the clipping in whites.
The first frame is over exposed. Whites clipped and skin tone clipped. Colour curves make a big improvement to the low lights.
Of course, maybe you want that extreme contrast look. Not all displays handle well super whites and super blacks.
smashguy37 wrote on 3/8/2010, 4:54 PM
I realize some of it is clipped, yes, it didn't help most of them wore white shirts, but I was working off a Canon XH A1s LCD screen so it's tricky to make an accurate guess, because sometimes some of the shots look under exposed to me.

I played with curves to get a better black, but combined with the colour I'm seeing, it looked kind of ugly. I'll play with it some more.
Jay Gladwell wrote on 3/8/2010, 5:13 PM

"... I was working off a Canon XH A1s LCD screen so it's tricky to make an accurate guess, because sometimes some of the shots look under exposed to me."

Doesn't the camera have a zebra pattern?


smashguy37 wrote on 3/8/2010, 5:32 PM
It does...somewhere. To be honest, I forget where it is, but it's certainly not a preset button or switch already on the body, I think it's buried in the menu for use as a custom function.

I purposely let some of the stuff overexpose, and maybe I'm off here, but the place it was shot doesn't exactly have consistent lighting (trees and tall bushes all around) so I didn't want to make the rest of the image seem too dark. This was just a quickie thing banged off in an hour.

Here is my adjustment (I know some whites are still over 100 IRE):
http://img709.imageshack.us/i/57810751.jpg/

And the original:
http://img697.imageshack.us/i/noccf.jpg/

My adjustment, besides curves has some slight CC on it. That's just based off my screen though.
smashguy37 wrote on 3/8/2010, 5:38 PM
And two more:

This skin seems somewhat off to me:
http://img535.imageshack.us/i/orangeskin.jpg/

Compared to:
http://img63.imageshack.us/i/goodskin.jpg/

Thanks so far guys...
Serena wrote on 3/8/2010, 6:01 PM
The XHA1 doesn't have zebras, which surprises me. You could experiment with the gamma curve knee function. In video it is generally better to under expose because detail recorded is better than detail lost. But with only an 8bit dynamic range, too much under exposure makes for noisy darks so often less important highlights (e.g. clouds) have to be allowed to clip. But the knee function will help a lot. The difficulty with skin tones (white, at any rate) is that they're easily over exposed and turn orange (a common video look; R clips or compresses first) so it pays keep them at about 65-70% max.
Jay Gladwell wrote on 3/8/2010, 6:51 PM

Yes, it has a zebra. Look on page 64 of the User Manual (download PDF version here--just right click and save) and read all about it. More importantly, learn how to use it! Then you won't have all these exposure issues.


Serena wrote on 3/8/2010, 7:34 PM
I did say I was surprised. But I only looked up the brochure. So set zebra to 65-70% and use this to guide exposure when you've got white people in frame. Like everything else, test.
smashguy37 wrote on 3/8/2010, 7:37 PM
I don't own the camera, so I can't jump into it right away, but I'll make a point of finding the zebras.

Like I said, I was 100% aware I was clipping, I did that on purpose because when I have avoided doing it in the past, the image seems to get too muddy -- I'm still playing the camera to find a happy medium, but some of the shots I did for that shoot weren't clipped (I posted the brighter shots). I didn't want to brighten the shot in post (the darker areas) and end up blowing out the whites anyway.

Normally I would keep the zebras handy (it's stupid simple to set on my GL2) but I didn't notice it off hand going through the menus a couple times in the past. I still can't even figure out how the change the presets (CineV, etc.) to do stuff like negative gain. That link doesn't seem to work BTW, but I'll try to Google it.

Anyway, I'm aware of the whole clipping factor, I just wanted some more experienced opinions on the colours, because every now and then I get that orange skin look and sometimes I don't.

Thanks guys.
musicvid10 wrote on 3/8/2010, 7:38 PM
"orangeskin" is still slightly blue in the mids, but not off by much.
"goodskin" is by far the worse of the two. More blue than the other.

Something isn't quite right with your viewing setup -- monitor color temp maybe?

smashguy37 wrote on 3/8/2010, 7:46 PM
Yikes, yeah my monitor must be way off. I normally don't do these projects at home on Vegas (wanted to play with V9 some more) so I had no idea.

I'm running a Geforce 9600GT video card, and I think it's "control panel" is just set to the factory setting...all sliders seem to be in neutral spots. I'll try it's calibration tool.
smashguy37 wrote on 3/8/2010, 8:20 PM
I tried a program called Monitor Calibration Wizard, went through the steps and A/B'd the default and my calibration and the only difference once the screen got slightly darker with more of a blue tint to it, but the overall orange skin still looks about the same to me.

I'll see how it looks at work and on some TVs and experiment a bit.
Serena wrote on 3/8/2010, 8:34 PM
The nVidia control panel contains 3 reference images and the first one (colour bars) is somewhat useful. Set brightness so can just see the lighter black bar (bottom RHS of image: turn up brightness if you can't see it and then adjust down until almost gone). Adjust contrast until lower edge of white square (bottom LHS) just disappears. That's the basic setting. You then have to get RGB separately adjusted (brightness, contrast, gamma) which is not so easy. And you must recheck brightness and contrast after those adjustments. If you have the VASST "Color Correction Sony Vegas" it includes a veg and guidance that is useful for setting up domestic monitors. Otherwise something from http://www.drycreekphoto.com/Learn/monitor_calibration_tools.htmreview of other systems[/link] might be worthwhile.
musicvid10 wrote on 3/8/2010, 8:39 PM
Monitor color temperature is set using the physical monitor controls, not the graphics card adjustments.

It should be set to its native color temperature before attempting any graphics card calibrations. Sounds like yours is set warm.
musicvid10 wrote on 3/8/2010, 8:58 PM
Quickest way to identify a color display problem is to throw a grayscale on the screen.
Here is one I designed ten years ago that can be used for both monitors and printers.
There should be relatively little color cast in the midtones, as close to a slightly "cool" neutral as possible, and some differentiation at both ends when viewed in a graphics editor.
[Make new post if you want the file]