Where is Lift and Gain in VP6 Colour Correction?

discburn wrote on 12/22/2017, 8:14 AM

I’ve always had trouble brightening the blacks in VPX6. Increasing 'Brightness' lifts the blacks up off the 0 line in the Waveform Scope, but makes the whites too bright and milky. To bring the whites down, and keep the blacks where they are, I’ve had to play wth contrast, gamma, etc. never really to my satisfaction.

In other NLEs it’s a simple process of adjusting the 'Lift' for the blacks and the 'Gain' for the whites. This keeps everything nicely balanced in the Waveform Scope, and adjusting the 'Gamma' allows brightening and darkening without moving the black and white bottom and top lines respectively.

Can anyone throw some 'light' on the subject?

Seamus

Comments

johnebaker wrote on 12/22/2017, 2:28 PM

Based on the definition of Lift and Gain, that I was taught, the VPX equivalents would be the Gamma Lows and Gamma High options in the Brightness/Contrast, Gamma dropdown

HTH

John EB

discburn wrote on 12/22/2017, 4:43 PM

Thanks John,

I’ll try out those!

Seamus

browj2 wrote on 12/22/2017, 10:29 PM

Hi Seamus,

I use what John EB mentioned along with HDR Gamma. I'm just starting to learn about how to use the curves you see below.

It may be time to upgrade.

John CB

discburn wrote on 12/23/2017, 3:49 AM

That's neat. I haven’t been able to find any step-by-step tutorials about colour correction or grading in VPX. Anybody got links?

Seamus

johnebaker wrote on 12/23/2017, 4:28 AM

There are many tutorials on colour grading/correction on Youtube, however they tend to be in German.

However there are many tutorials for other video editing about color grading, and most of them can be applied to VPX with appropriate changes to terminology eg Lift/Gain to Gamma Low/Gamma High etc.

The Vectorscope, Waveform monitor, RGB Parade, Histogram, Curves and Color wheel tools are fairly standard across video editing programs.

One of the best techniques for colour correcting I have found is 'Colour correcting by Numbers' in principle you fix the colour casts of the blacks, grays and whites, these must be present in the video/image, the technique will not work without these neutral 'colours'. The colours automatically take care of themselves as in the example below - which has a distinct blue cast when compared to the corrected version.

Using this technique avoids colour bias caused by uncalibrated monitors, lighting,and user visual biases.

HTH

John EB

discburn wrote on 12/23/2017, 5:52 AM

Hmm... 'Colour by Numbers'. Just googled that. I’ll put it in my back pocket for the moment, while also getting to grips with LUFS for audio. Thank God Samplitude Pro X3 Suite has that on board!

Seamus