Masks

Masks are used to reveal or conceal part(s) of an image. ProShow has two mask types: Grayscale and Transparency. They differ only in how mask colors are interpreted. That is important because mask colors can have an impact on what is revealed or concealed. What is important is how the mask’s color is interpreted.

GRAYSCALE MASK
The intensity of this mask is affected by the layer’s color and alpha channel’s setting. Grayscale masks work on the idea that light reveals and dark conceals. So, those parts of an image that exist immediately below light mask colors will reveal the image. Likewise, those parts of an image directly below dark mask colors will be concealed. The amount of reveal or conceal is directly related to how light or dark the colors are. The extreme case is when the light color is white and the dark color is black. All other colors create a translucent mask.

TRANSPARENCY MASK
The intensity of this mask is affected only by the layer’s alpha channel’s setting. Transparency masks care nothing about the mask’s color. So, any color of mask is acceptable and you get the same result regardless of the mask’s color. Any part of the image immediately below the mask layer is revealed, the rest of it is concealed. That means that if the mask layer is smaller than the image layer, only what is immediately below the mask layer is revealed. What you end up with, in this case, is an image portion that’s the same size as the mask.

INVERTED MASK
An additional consideration for your masks is that they may be inverted. That is, when inverted, what once revealed now conceals and what once concealed now reveals.

ALPHA CHANNEL AND OPACITY
•    How opaque or translucent a mask is depends on the settings of the layer’s alpha channel. The content of the layer may have been imported with opacity already set on the alpha channel. ProShow can adjust that opacity using the opacity settings, starting from the existing opacity setting to full transparency. ProShow cannot decrease a layer’s prior existing transparency
•    ProShow provides the means to vary each layer’s existing opacity using the opacity function. This function is actually varying the layer’s alpha channel setting. Whatever the existing opacity of the layer is upon import or creation, the ProShow opacity function changes it by 0% to 100%.

ProShow lets you select any layer as a mask, as long as it is not already under a mask, the layer immediately below the layer you want to designate as a mask is not a mask, is not an adjustment layer, or is not the very last layer in the layer stack. The layer may be a graphic, an image, a video, a solid layer, or a gradient layer. There are advantages and disadvantages to each. The situation in which you working will often determine the mask you use.

140525-0835  © Copyright Dale Fenimore, All Rights Reserved