Working with areas of a curve

[derekfountain]

Just thinking a bit harder about my previous thread which describes marking an area of a curve and having that area reflected on the image, something else popped into my head. I'm frequently getting annoyed at having to try to 'lock' parts of a curve that I don't want to move. Suppose I've worked hard to get the highlights part of a curve looking right, I then add another point to begin work with the shadows end, but when I move it it moves the lower part of my hightlights curve. So I have to go and add a couple of points just below my highlights area in order to pin that part of the curve in place.

Wouldn't it be nice to be able to mark an area of a curve as 'locked' such that pulling and pushing other parts of the curve definitely won't move that 'locked' area? The concept is addressed in current versions of CM with the curve context menu options that allow you to pin the top right, bottom left or whole of a curve. This works, but it's a pretty blunt tool, just adding a couple of points to hold a large area of the curve.

Here's what I thought: imagine the Photoshop rulers - two narrow 'channels' that appear along the sides of the image. You can drag guides from them. Now imagine two similar channels along the sides of your curve grid that could be used in a similar way. Take the horizontal channel along the bottom: you drag one 'curve guide' in from the left and another in from the right marking an area in the middle of the curve. Now any changes you make to the curve only affect the 'active' area of the curve in the middle. The 'masked off' areas of the curve to the sides are not disturbed.

You could use these curve guides to implement my other idea: drag the curve guides in and hold the Alt key (or something) to see the pixels of the image represented by the area between the markers.

Ramble ramble... This idea isn't fully cooked yet... :)

[mikemeister_admin]

Suppose I've worked hard to get the highlights part of a curve looking right, I then add another point to begin work with the shadows end, but when I move it it moves the lower part of my hightlights curve. So I have to go and add a couple of points just below my highlights area in order to pin that part of the curve in place.

This works, but it's a pretty blunt tool, just adding a couple of points to hold a large area of the curve.

Ramble ramble... This idea isn't fully cooked yet... :)

In such a case , I use whole grid pin and delete the pins where I will work.
you can also put extra pins near the working point (s).
So areas are locked!

[mikemeister_admin]

after you have changed the curve, you can use whole grid pin again and again and again and/or deleting some points.
Sometimes I need to delete 1 point to get my goal.
also sometimes extra points are needed.
also you can shift the point (s) along the curve. Enough possibilities.

Frits

[ggroess]

Hey Derek,

Are you thinking like a cropping scissors for the curve...area outside the croping is locked?  Interesting I wonder how the CM would make that happen??  Mike, is it possible to narrow down the area of the curve like that??

Greg

[-default]

This is a good idea that is partly addressed with "Pin Grid".  You're correct that it could be done even better than that.  For now, I'll add this to the list of possible features for CM3.