Video color correction: filters vs. white balancing?
Posted 08 December 2006 - 02:06 PM
I don’t shoot much video, but I’ve noticed that digital still camera RAW images shot under tungsten are often very close to the limit of the RAW converter’s adjustment temperature scale, while images shot in daylight conditions are typically right in the middle of the scale, giving much more room for adjustment.
I searched the forum and read the chapter on filters by Ira Tiffen in the ASC Video Manual, but I can’t seem to find anything definitive. Mr. Tiffen’s article states: “Color Conversion filters are used to correct for sizeable differences in color temperature between the internal video correction and the light source.” He doesn't elaborate.
So, I’m wondering, are video chips and/or sensors designed to record colors most accurately at a specific color temperature? Does simple in-camera white balancing produce the same effect as filtering?
Posted 08 December 2006 - 02:20 PM
So, I?m wondering, are video chips and/or sensors designed to record colors most accurately at a specific color temperature? Does simple in-camera white balancing produce the same effect as filtering?
They are, if you get a chance to test a Viper in film stream (no white balance possible) you will see that they are optimised for 3200K
If you set the filter wheel first on a normal video camera first, then yes. If you white balance with the wrong filter then the signal is less clean.
Posted 19 December 2006 - 05:48 PM
Posted 19 December 2006 - 09:28 PM
The problem is that different video cameras are designed to work natively at different color temperatures. Some are best near tungsten, some near daylight. Usually this is not a published specification, unfortunately. If you can figure it out, by all means, get it close with a filter, fine tune with manual white balancing, and finish in color correction.
I don't think it paints a complete picture to talk about color correction without mentioning white level clip, black level compression, and black stretch. There are scenarios in which a Panasonic MX-50 digital switcher with built in independent black and white clip levels offers more of what I need to adjust a scene than the highly valued Sony Component color corrector that was very popular in the 90's but had no function.