Curve tool, no illegal values?

[jeff webber]

Hi all,
I had a few days to use a scratch system the other day. I discovered that when grading with the curve tool, I don't get any red bars on the RGB PARADE when crushing blacks or blowing out brights.
If I use any other tool set, (color wheels) I get the red warning bars.

Can anyone explain the reason this happens in this wonderful system?
Thanks,

jeff

[Willy Sacul]

Not too sure but I think it has something to do with "remapping'?
I only used scratch for a few days.
Maybe a scratch user with more experience can chime in on this one.

Then again, after seeing that this post has over 40 views & no replies, I'm guessing that they don't know the answer either (LOL)

[John Tissavary]

That is the nature of the two tools. Curves are fixed at black & white points, whereas the two outside 'color wheels' (lift & gain) are not - they are able to move pixels at the black & white points, which is their purposel.

BTW, you can move the black & white points of curves by grabbing the vertices at the very ends, but that's not typically what people do with them.

regards,

John T.

[Dane Henry]

What John said.

Another way of saying it is that curves work WITHIN the constraints of a clips current white and black points. You typically raise or lower these to desired levels with your lift/gain, shadow/highlight contrast controls before working with the curve tools.

-Dane

[jeff webber]

What John said.

Another way of saying it is that curves work WITHIN the constraints of a clips current white and black points. You typically raise or lower these to desired levels with your lift/gain, shadow/highlight contrast controls before working with the curve tools.

-Dane

Wow, I thought that JOHN meant just the opposite. ("Curves are fixed at black & white points") That the curve tools sets the B & W points???


Just to be clear, with Scratch,
If I want to grade Broadast safe, I would set the color wheel (Black) to 7.5 and then I could use the curve tool to crush the blacks as much as I want and it will not fall below 7.5?

[John Tissavary]

That's correct. Once you set your black & white point, curves will not alter those, just what's in between.

[jeff webber]

Ok Great, thanks