How PS Gradients Change With "Smoothness" and "Method" Options

[thebestcpu]

Having done some work on Gradients recently, I wanted to understand how the Smoothness and Method Options change the Gradient's characteristics.

Smoothness can go from 0% to 100%. The Method option has three settings: Classic, Perceptual, and Linear.

Using Smoothness limits of 0 and 100 gives six total options to consider.

To make the explanation simple, I created a B&W gradient that goes from Black up to White halfway through the Gradient and then back to black and the end of the Gradient.

Here are the Color Stops when looking in the Gradient Editor.




Side by side below, I show the resulting gradients on top with the six combinations of settings with a graph of the gray level across the Gradient in graph form (extracted from the Gradient).

Here are my basic observations for the settings.

At the far left is Smoothness = 0 and Method = Classic (the only Method available before PS 2022)
This mode is precisely linear, yet at the peak, the appearance appears to have a bright band. The optical illusion is natural to our eyes.

The optical illusion is the main reason to have the Smoothness Slider. With Smoothness at a higher level, as seen in the following Gradient, the bright band disappears. All it took was making the change in brightness smoother. Eliminating the optical illusion makes a higher Smoothness setting desirable in many situations.

Note in the options, where Smoothness=0, there still is a small band in the middle independent of the Method used.

That covers the impact of the Smoothness slider.

If you look at the two gradients drawn with the Perceptual Method, there is a pull-in of the blacks, similar to a gamma function shape pulling down the blacks more than whites. For me, visually, the Perceptual mode makes the 50% gray point on both sides of the triangle about halfway through the ramping up in brightness and about halfway back to Black. In some ways, this gives it a more balanced look.

If you look at the two gradients drawn with the Linear Method, there is a bulging out of the whites, which, when also using the Smoothness setting of 100, makes a very smooth-looking gradient.

So which one you use depends on your needs.

I hope this summary and visuals will help others as it helped me better choose which of the six options to use under different circumstances.

John Wheeler

 

[amitclint]

Thanks for this gradient change combinations. These are really helpful for someone who is designing and can select the gradient as per circumstances.

 

[thebestcpu]

Thanks for this gradient change combinations. These are really helpful for someone who is designing and can select the gradient as per circumstances.

You’re welcome @amitclint

 

[thebestcpu]

I have not used all of the new modes along with smoothness variations for very long. Yet will share what I know how to use them.

- If you need to have perfectly linear gradient from a color number perspective, the using the smoothness = 0 and using mode as Classic is needed. The only need for this specific situation of what I am aware is for mathematical or scientific analysis. That is a very narrow/specific need.

- In any case where you have a gradient created with several segments (i.e through a preset or custom gradient editor), I recommend that you keep the smoothness at or near 100. This helps create a smoother transition and avoid the optical illusion of bright spots within the gradient.

- Fro the three modes of Perceptual, Linear, and Classic here is an Adobe helpx link for Adobe's explanation: https://helpx.adobe.com/photoshop/using/gradient-interpolation.html For me, those explanations are pretty vauge yet that is the best I have seen so far. After examining what the Perceptual mode does, I personally would use it with caution. It is the equivalent of moving up the black point (this can possibley cause loss of data in the dark areas by clipping) along with a slight bit of reduced gamma (center slider on the Levels Adjustment Layer). For the Linear mode that is the equivalent of raising the output level of the blacks a bit and adding a positive gamma (center slider on the Levels adjustment curve). No image data is clipped and particularly the shadows are lifted.

The above is the technical result of using the various modes to give you a feel for what they do. Sometimes if just takes using them and see which gives you the desired results.

I hope these details help some
John Wheeler