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8 votes
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What is the difference between levels, curves and contrast settings in post processing?

Yes, your assumption is correct. A levels control is basically the equivalent of a curves control that can only be adjusted at the end points and one point in the middle, while a contrast slider is (...
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4 votes
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Why does Photoshop Curves in 16 bit color depth still use tonal range 0 - 255?

16-bit is only used for internal calculations. What you actually see on your monitor is in 8-bit. Since an 8-bit monitor can only display 256 levels (0-255) and is unable to display the difference ...
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4 votes

What is the difference between levels, curves and contrast settings in post processing?

I look at them kind of like sandpaper for a woodworking project: The Contrast slider is the really coarse paper that you use to get in the ballpark of the final shape you want, the Levels sliders are ...
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3 votes

What does "normalizing the curve" mean?

What your colleague meant, based on your description, was: Setting the white and black point of the image. On an 8-bit grayscale image, you have 256 different values ranging from total black (0) to ...
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  • 318
3 votes
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Is it possible to simulate any color-only filter with curves?

Hum. You can not do some transformations with curves alone if your image is on RGB mode. All depends on what information you have on each channel. Here is a simmilar question: What's the best ...
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3 votes
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How to find curve that correspond to a given transformation?

You say: I suppose that all the transformation we can make to an image which operate on one pixel per time (for example levels, saturation, color balance) can just be done with curves. This is not ...
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  • 2,833
2 votes

How are the levels and curves tools related?

A few years late, but I think it contributes. The Curve Tool can directly do anything that the Levels tool can do. And a bit more too, but the curly curved "curve" part is simply one option, but the ...
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  • 12.5k
2 votes

What is the difference between Photoshop RGB Curve and Lightroom RGB Tone Curve?

LR uses ProPhoto with a gamma of 1 for calculations, but it uses a gamma of 2.2 for the interface (histogram, tone curve). Photoshop uses whatever gamma is correct for the chosen color space (2.2 sRGB,...
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2 votes

What's the best method to change colours in a photo to another specific color?

The basic answer is that you can only modify with curves (do not use levels) If and only if you do have the primary color component on the mix, and you can only shift the colors to some degree. You ...
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2 votes

Why does Photoshop Curves in 16 bit color depth still use tonal range 0 - 255?

Habits (or compatibility with a legacy of thousands of Youtube tutorials out there...). Actually what would make sense is a 0.0->1.0 scale or percent values (with fractional part). These values are ...
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  • 16.7k
1 vote

What change does tone curve make in pixels in a colored image in Photoshop and Lightroom?

Notice that the tone curve is set to represent light... it doesn't matter if the image is grey scale or color. In color the 0-255 value of each channel represents the brightness of the tone (i.e. Red, ...
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1 vote

What's the best method to change colours in a photo to another specific color?

You can't, easily, because hues other than pure red, green, or blue are made of mixes of those colors. If you want to increase or decrease the proportion of one of these in a constant way, the levels ...
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  • 140k
1 vote

How to find curve that correspond to a given transformation?

At best you can only makes guesses because you'll have no way to know if it was only one curve applied to the entire image. For example when I'm working on nearly any photo I almost always have a ...
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1 vote
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What's the best method to change colours in a photo to another specific color?

RGB is fine for minor changes such as going from blue to cyan, but if you want to make major changes you should learn how to work in LAB. LAB's separation of color from luminosity into two distinct ...
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  • 2,331
1 vote
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Programming curves tool how to work with RGB (combined) channel

You should apply the LUT to each channel. If you are really interested in image processing theory, then you should start a new question asking for book recommendations on the subject, if it hasn't ...
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