Color correct

macs

macs

Well-known member
I have footage thats been shot in a car, inside the car its just a little bit dark but i can live with it, but, the outside is really blown out, almost all white. Do you have any idea how i can fix this. I want to lower the with outside with making the person inside to dark...

thanks
 
Use the three way color corrector. You can bring your whites down and bring the mids/blacks up.

Duct Tape Films said:
Use the color correction tools. Basically follow the instructions in the manual. What you'll do first is set the auto contrast. Then you'll set the white point, and black if need be, grey point only if you actually used a reference. You probably don't actually want to raise the highs, because all you'll get is blown out crap, and chances are what you're looking to raise doesn't live there anyway. Actually the luminance level you want to raise is likely somewhere in the lower mids (or probably better, lowering the other values instead). Knowing your luminance values is the key here. Here's kind of a breakdown....

0-40 Black and Near Black
40-80 Low Mids - Dark Grey Blue or Red shaded shadows, darker purer colors, darker browns
80-180 Mids (Nearly everything that appears "lit", not including light sources, also includes lighter shadows)
180-240 High Mids & Brights (Lighter than mids, but not white)
240-255 White and Near White*

*many times things that appear "white" are actually shades of red, blue, or green with a high mid luminance value. Examples of white and nearwhite that would actually have that highest of luminance values are light sources, clouds, reflections in eyes, whites of eyes, blown out windows, etc. Generally the highest lum value, or maybe doesn't even exist in the frame if you exposed as such.

Here is a RGB color list that a scientist compiled that lists nearly every "painter's" color (ex. Mars Black, Cobalt Blue, Burnt Sienna, etc.), to be used for graphic designers and such. I find it incredibly useful in indentifying the exact luminance value of a given color in a frame as you can always convert RBG values to LHS values for reference.

http://local.wasp.uwa.edu.au/~pbourk...r/colourspace/

FCP breaks these down slightly different, and works in percentages (0-100) as opposed to straight luminance values, but the same theory applies. It's just like sound frequencies. A human voice only resides in a certain frequency range, just as a shadow only exists in a certain luminance range. The color correction tools can get you there.

A last resort for underexposed footage would be to layer it with a copy of itself, using likely an Add Scaled, Multiply, or Soft Overlay method. Your mileage may vary. The trick is to keep the blacks and whites at their optimal places, and futz with the mids. Lowering the Gamma may also give you a little more light, although also a last resort if you can't do it with CC.
Click to expand...

Quote originally taken from this thread:
http://www.dvxuser.com/V6/showthread.php?t=68077

zach
 
Blown out is blown out. Digital is reverse from film... in an analog world you can lower those whites to get detail...

Not so in Digital world. What you shot is what you got!

CaptM
 
Captain Mench is right. You can lower your whites... to gray. Probably not what you want. Once they hit 100% white it's over, unless you do some tricky compositing.
 
I going to lower my whites as much as i can and live with it. I didnt have any ligthing in the truck so ligth the driver and lower the light outside. Im desaturing my final output a little so its helping a little... But its better to see the guy than to see whats happening outside!!

Thanks for your help
 
macs said:
I have footage thats been shot in a car, inside the car its just a little bit dark but i can live with it, but, the outside is really blown out, almost all white. Do you have any idea how i can fix this. I want to lower the with outside with making the person inside to dark...

thanks
Click to expand...

Limit your 3-way color correction changes to only the whites. There are examples of how to do this in the manual, follow them, but apply it to your situation instead. After that, do a secondary color correction to only the interior of the car's luminance values. After you get something that is looking closer to your ideal, do a third pass, as to match it to neighboring clips or sequences. It's probably going to take a few tries at this your first time out, so be patient with yourself, and keep picturing in your mind how you want it to look. You may or may not get it there exactly, but with patience you may be able to get a good deal closer than you are now.

Alternately, if you cannot for the life of you save the footage the way you want to, you may find that since you have a blown out background, an alterior "fix" may be to go with that "look" intentionally, simply giving in to the source footage's characteristics. In this case, take what appears to be the problem (exposed for neither the interior nor exterior of the car), and exaggerate it further, so much that you're left with silouettes, and fully blown out windows (DO use Broadcast Safe, nonetheless). Many times unfixable material can be made usable by making it look like a choice instead of an accident. It's like the old axiom for musicians performing live, "If you make a mistake, do it two more times, and then it's no longer a mistake". There is an art to this, you know.
 
Last edited:
You can also matte it out. I've done that a lot. Just did it for a bad shot I was forced to use in a music video. I take a still, go into PhotoShop, Studio Artist, whatever, make a black and white matte. Place it on a video track above your original, and give it a Gaussian Blur, then set it's Composit mode to something like Mulitply or Difference. I can get blown out areas undercontrol quite a bit using this on top of color correcting the original clip.
 
With most DV cameras, if it's blown out you can still rescue it a little bit.

DV records in Y'CbCr format, where Y' is the luma channel that represents brightness. FCP calls this YUV, which is wrong but most of the computer world calls it that.
Black level is at 16 (Y'). White level is at 235. Most DV cameras record information above 235.
On FCP's scopes, 0 (FCP) corresponds to 16 (Y') and possibly values below it (that would be a FCP bug). 100 (FCP) corresponds to 235 (Y').

To bring the extra highlight values into legal range, put the following number into the white point in the 3-way CC (numeric controls):
235 -16 (or 219)
That should perfectly bring in the illegal values into legal range.
Adjust chroma too, since chroma should be proportionally tied to luma (this is a weird concept that I don't know how to explain right now). But you need to change it by 219 / 235.... or something like that (sorry, can't remember because I'm not sitting in front of FCP).

2- Lowering the gamma will also bring out more detail. The multiply composite mode is one good way of doing this.

The mid controls in the 3-way CC lower gamma on the Y' channel (instead of the R, G, and B channels) which doesn't look good all the time. But you can try that too.

3- Some sort of artistic effect could also work... i.e. glows.
Duplicate the video onto itself.
Apply gaussian blur to top layer.
Set opacity to 50%.
 
You must log in or register to reply here.
Back
Top