where can i find info on using yc waveform, vectorscope, YCbCr & RGB Parade??

P

Paunch

Well-known member
I've been frantically searching the web for information on how to use these and what adjustments to make to my footage to make it more compliant with regard to the levels, saturation, contrast etc etc....but can't find anything helpful....anybody know of where I can find some decent explanations on this stuff?

t
 
Hey Paunch- there is an excellent CC book available and I will try and find the link for you but I suggest you dont over complicate this for your self.

Basics:

Start with Levels and the waveform (forget about the rest initially).

Put some color bars in a timeline and observe where the Black and the white levels sit in the waveform. You will see it shown quite graphically. (as steps).

Note" that the Color bars are a universal reference so all the components from white to black will show acurately positioned on the waveform. (There are two types of color bars but we wont get into that at the moment)


White is highlight and black is Shadow. Anything in between is gamma (greys) and these are the mid tones that make up the detail of any greyscale or color image. Think about everything in greyscale tones though and forget the color information for the moment.

Apply a Levels effect to the bars and have a play as you watch the waveform.

When you grade your actual image using levels control and the waveform monitor you "decide" where you want Whites and Blacks to sit on the scale. It is not compulsory to have Whites and blacks at exact level as per the Color Bar reference. eg in the case of a night shot where whites objects would not be seen as white and blacks would be very crushed - you would drag the whites to a lower level in the waveform.

Once you set White and Black levels for a particular image you work on the gammas - midrange tones. You also set these where you want the image to be according th the "feel and look" eg lower skin tone levels inthe case of a night scene.

The reason you set levels first then mess with the color controls is that the color / hues change with the level (Bright/dark control) and you can end up chasing your tail.

Remember that Grading and CCing are as much about feel / look as they are about technical factors but if you are broadcasting the technical issue of White/Black levels and Safe colors become important.
 
thanks for that very informative answer.....your referring to the levels effect right? Now I notice that the values can be adjusted for both the input and the output, which should i be tweaking?

Can I also use the 3 way color corrector for these tweaks of the luminance, or is it best to use the levels effect?

When dealing with levels, and viewing the information on the waveform should i be pulling the black levels down to as close as i can to 7.5 ire and pushing the whites up to just under 100 IRe and adjusting the mid tones to at least 70IRE (i read that properly exposed images usually fall in between 70-100 IRE for midtones) to ensure a better image??

I understand that the values for the shadows (blacks) and highlights (whites) need not exceed certain limits in the waveform monitor so is it recommended to adjust all the levels to ensure a much more balanced picture???

I appreciate all the feedback you've given me so far, i can always count on dvxuser to find the answers.

cheers,

tyler
 
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Use whatever tool has Levels Control but...

Levels Effect is easy to use and then you can apply 3 Way CC effect separately for the next step of the grading exercise.

Do the INPUT LEVELS

You are correct in your understanding of the 7.5 to 100 IRE scale (7.5 IRE is base level black for NTSC and 0 IRE for PAL)

Note: it is not actually neccesary to have a technically balanced picture because its a creative thing... but it is important to do the Levels thing first before color correcting. ie all images do not have to have black BLACKS or white WHITES.

Play around with my suggestions and even try doing it the other (wrong) way. eg do a color correction then adjust the levels. The colors will shift away from what you set.

Another reason to set Levels first is if you are going to use Look effects like Magic Bullets or LOOKS. They respond best to a full levels image.
 
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