The Effects tab sheet offers dehaze, grain and vignetting
effects.
Texture
The Texture effect lets you smooth skin area or emphasize textured details in photos. Negative values make skin look softer whereas positive values produce enhanced texture details in various image areas. This slider requires at least Camera Raw 11.3 and Photoshop Elements 2018. Otherwise it will not be visible.
Dehaze
The Dehaze effect tries to remove the veil of haze from photos, which means that skies get darker and the contrast is increased. So unlike the Clarity slider from the Basic tab sheet it also changes colors and brightness slightly. With negative slider values you can even add a fog effect to your image. Set the slider to zero to deactivate the effect. The Dehaze feature does not work in Photoshop Elements 11 and requires at least Camera Raw 9.1 in newer versions of Photoshop Elements.
Grain
The Grain effect adds film grain to photos. This can be useful to simulate an old look, e.g. together with the Grayscale effect from the HSL / Grayscale tanbsheet, or to make photos that have a strong noise reduction applied look more natural again.
The Amount slider controls the effect intensity and blends the grain into the image. Set the slider to zero to deactivate the effect again. The Size slider determines the size of the grain particles that are added. The Roughness slider is best kept at a value of 50. Lower values add less coarse noise but reduce the contrast of the noise, which makes it look flat. Higher value slider increase the noise contrast, which make the noise appear more obtrusive.
Best zoom the preview image to 100% to have a more precise look at the the grain effect.
Post Crop Vignetting
Whereas the Vignetting controls on the Lens Corrections tab sheet remove vignetting in order to fix a lens imperfection, the Post Crop Vignetting effect is meant to apply a vignette effect for creative purposes. Additionally as its name suggest it is applied after the image is cropped in the image processing pipeline whereas vignette removal is applied while considering the original image size.
The items of the Style combo box control how the vignette is blended with the image, so you could compare this setting with the blend mode of a layer that contains a vigenette image. The Hightlight Priority and Color Priority options produce very similar results. However, the Hightlight Priority option tries to protecting highlight contrast but can lead to color shifts in dark areas of the image. The Color Priority option tries to preserve color hues but loose of details in bright highlights. Usually you will not see a difference between the two for most images. The Paint Overlay option produces a softer vignetting effect but may reduce highlight contrast.
You can use the Amont slider to add a black or white vignette to the corners of the image. Negative slider values darken the corners whereas positive brighten them with a white vignette effect. The larger the slider value, the more the effect moves towards the center of the image. The Midpoint slider lets you move the vignette more towards the center with negative slider values and more towards the corners with positive slider values. Unlike the Amount slider the Midpoint slider does not adjust effect intensity while doing this.
The Roundness slider changes the shape of the vignette from a rounded rectangle to an ellipse to an circle. To get an elliptical shape you have to use a slider value of 50. Lower values transform it into a rounded rectangle and higher ones into a circle. The Feather slider defines the size of the transition area between the opaque corners and the fully transparent center. A slider value of zero provides a sharp edge vignette whereas a slider value of 100 produces a rather diffuse vignette.
Finally, the Highlights slider only becomes active for negative Amount slider values and the Highlight Priority and Color Priority options. The Highlights sliders lets you remove the black vignette effect from the highlight areas of the image. This helps to avoid that the bright areas are dimmed too much by the vignette.
To deactivate the effect again set the Amount slider to zero.