Overlay

MI
Posted By
martti_i_lappalainen
Dec 19, 2006
Views
288
Replies
3
Status
Closed
Hello,

Iam struggling with an exercise which includes High Pass filter. When using the filter the image turns gray. The next step is to change the layer blending mode to Overlay which makes the gray invisible and reveals the sharpening effect. How come the Overlay blending mode makes the gray disappear? I have also seen somewhere that 50% gray is Overlay neutral color. I do not grasp this Overlay versus gray stuff, can someone please explain it to me?

Thank You,
Martti

How to Improve Photoshop Performance

Learn how to optimize Photoshop for maximum speed, troubleshoot common issues, and keep your projects organized so that you can work faster than ever before!

B
Bernie
Dec 19, 2006
From the help file:

Overlay

Multiplies or screens the colors, depending on the base color. Patterns or colors overlay the existing pixels while preserving the highlights and shadows of the base color. The base color is not replaced but is mixed with the blend color to reflect the lightness or darkness of the original color.

In plainer (and less precise) English:

1) When applied to a colour neutral image on a layer (read greyscale image, but in RGB mode), overlay only changes the density of the layer below, not the colour.

2) If a pixels’ colour value is is lighter than 127 it will lighten the pixel below, if it is darker than 127, it will darken the pixel below and if it is 127, it does not affect the layer below.

Since 127, 127, 127 affects neither the colour balance, nor the density of the image, it is the neutral colour for the Overlay blending mode.
GA
George_Austin
Dec 20, 2006
The "high-pass" terminology may mislead you. Here you are dealing with SPATIAL not temporal rates of change. Where there is little or no spatial variation in color value, the filter assigns a neutral (to the Overlay mode)mid-gray shade. At edges the change is abrupt and the shade assigned deviates from neutral. Sensitivity in terms of proximity to edges is controlled by the filter’s "radius" slider.

When the top high-pass filtered layer is in Overlay blend mode, mid gray values in that layer do NOTHING—as if the layer were not even there, the underlying colors coming through unchanged, corresponding to low-gradient-color areas. In areas of high variation, the underlying colors are either multiplied (darkened) or screened (lightened), so edges get sharpened and, again, the degree of sharpening depends on the radius value you select. You undoubtedly would set the radius by trial and error for the specific image being modified.
MI
martti_ilmari_lappalainen
Dec 20, 2006
George, Nomad,

Thanks for advice.

/Martti 🙂

MacBook Pro 16” Mockups 🔥

– in 4 materials (clay versions included)

– 12 scenes

– 48 MacBook Pro 16″ mockups

– 6000 x 4500 px

Related Discussion Topics

Nice and short text about related topics in discussion sections