Lightroom: How to use Tone Curve

For many years I neglected the Tone Curve panel.
I only really started to use it quite recently after noticing how many experienced users like it.
The more I use it, the more I realise how powerful it is
https://youtu.be/cGib3​rR8zG0

Great video. I'm relatively new to post-processing and this was very, very informative. Thanks for posting!

Many thanks Steve,
I am glad you found it useful

I don't understand how to get to the individual colors while using the tone curve. Does LR6 do that?

Bassat wrote in post #18546393
I don't understand how to get to the individual colors while using the tone curve. Does LR6 do that?

Hit the button at the bottom right of the Tone Curve block across from Point Curve: Linear
With it enabled you then can change the channel you wish to edit.

Got it. Thanks.

Thanks....always wondered, but was too lazy, to figure out what it does. I'll give it a whirl!

It is a very powerful tool, although it takes some time to get used to it.
Worth giving it a try

Bassat wrote in post #18546393
I don't understand how to get to the individual colors while using the tone curve. Does LR6 do that?

DagoImaging wrote in post #18546625
Hit the button at the bottom right of the Tone Curve block across from Point Curve: Linear
With it enabled you then can change the channel you wish to edit.

While I have made changes to the curve (not necessarily using Linear) in the past, I am curious as the PURPOSE of altering the curve for one color vs. another. Enlighten me about how this can be beneficial, please.

Wilt wrote in post #18554103
While I have made changes to the curve (not necessarily using Linear) in the past, I am curious as the PURPOSE of altering the curve for one color vs. another. Enlighten me about how this can be beneficial, please.

By using curve on the individual color channels (Blu/yellow, green/magenta and red/cyan) you can modify the balance of colors i your image, get rid of color cast, even modify the white balance.
You can do what can be doe with the WB tool and the HSL panel, but in a more precise way.
It does takes some experience to get the best results

It can be an easy way of either removing or adding a color cast to say just the highlights or shadows and have complete control over the transition. Yes, you can do this with other tools, but it can be easier with the curves. Of course more control also equates to less easy to use without some experience.

I use the color curves mostly in video because I start with a very flat picture style (and it is not a raw file) and when color correcting digital scans of film negatives. The latter takes quite some learning. But even though (I think) I am pretty adept at using them, for raw photos it's usually unnecessary or there are easier ways or I want to be more targeted and I'm in PS anyway, so I will use a color correcting adjustment + brush into a luminosity mask.

One thing about the color curves that can be useful is seeing directly where you are making the curves adjustments relative to the color histogram. IMO it is kind of specialized though.

Wilt wrote in post #18554103
While I have made changes to the curve (not necessarily using Linear) in the past, I am curious as the PURPOSE of altering the curve for one color vs. another. Enlighten me about how this can be beneficial, please.

Color curves are linear by default (they are actually linear log-log) so that the relationship of the R-G-B colors are technically correct for all tones from dark to light. So if you shoot an original with only gray tones, the reproduced tones will all be gray in the photo. Colors will all be reproduced as true. Sounds correct and obvious.

But you can edit the curves (which by default are not curves but straight lines) and make them curves. For instance, you can drag the R curve up a bit in the lighter part of the curve while leaving the ends unchanged. The red curve now bows upwards slightly. This has the effect of making those lighter parts of the curve redder without disturbing the rest of the colors in the image too much. This can effectively make skin colors look more attractive. You could also tune the other curves for particular purposes, for instance the G or B curves to make foliage look greener.

Color films of yore have imperfect color curves. That gives each brand and variety of film a different look. You can diddle the curves of a digital photo to simulate a color film look.

I use curves most to correct color problems in scans of negatives. Old negs fade, and the color layers fade at different rates. That results in a mismatch of the contrast of the colors. Visually what we see is color see-sawing - for instance pink highlights and green shadows. Those defects can be fixed by editing the curves in PP. The steeper the slope, the higher the contrast. The easiest way to adjust the contrast of a color channel is to change its white and black points. To do this kind of color adjustment effectively, you need a good eye to identify color balance in the shadow compared to that in the highlights.

Curves can also be manipulated for special effects. For instance, you could change the slope of one of the channels from positive to negative to get a kooky partial negative look.

ejenner wrote in post #18556549
It can be an easy way of either removing or adding a color cast to say just the highlights or shadows and have complete control over the transition. Yes, you can do this with other tools, but it can be easier with the curves. Of course more control also equates to less easy to use without some experience.

I use the color curves mostly in video because I start with a very flat picture style (and it is not a raw file) and when color correcting digital scans of film negatives. The latter takes quite some learning. But even though (I think) I am pretty adept at using them, for raw photos it's usually unnecessary or there are easier ways or I want to be more targeted and I'm in PS anyway, so I will use a color correcting adjustment + brush into a luminosity mask.

One thing about the color curves that can be useful is seeing directly where you are making the curves adjustments relative to the color histogram. IMO it is kind of specialized though.

I perfectly agree with everything, particularly on the use of Tone Curve with video

Excellent video and great thread!

Mcooper450 wrote in post #18568982
Excellent video and great thread!

Thank you!
I am glad you liked it!