Opacity verses Transparency


With the introduction of PowerCADD 7, Engineered Software has introduced a new opacity feature which allows us to independently adjust pen, fill and layer opacity . Well, what is it and how does that compare to transparency?


PowerCADD version 7.0 or newer and Mac OS? X (v 10.4.4 or newer recommended)


If you're already familiar with other applications such as Adobe Illustrator, Photoshop and InDesign, or if you've used Apple's Pages or Keynote applications, then you may already be familiar with the concept of opacity. However, the feature is new to PowerCADD 7 so let's begin with two simple definitions which lay the foundation for understanding the principles of opacity in PowerCADD 7

Opacity?: The condition of lacking transparency or translucence. We cannot see through objects which are 100% opaque.

Transparency?: The condition of being transparent or see through. An object which is 100% transparent is invisible.

In simple terms, transparency is the result of changing an objects opacity.

What does this mean?

In all versions of PowerCADD, prior to version 7, objects had two states. 100% opaque (we could not see through them) or 0% opaque (they were totally transparent). Think of a circle with a solid fill pattern. It obscured everything below it; the fill pattern was opaque. If that same circle had a fill pattern of Nil, we could see all objects below it; the fill pattern was invisible.

So, why is the new opacity feature in PowerCADD 7 referred to as opacity and not transparency?
In physical terms, we adjust opacity thereby determining to what degree information is hidden or revealed below. For example, an opacity of 100% hides all information below an object or layer . An opacity of 10% would appear almost totally transparent, allowing you to see through to objects below. In the example shown below, we adjusted the objects fill opacity from 100% (solid) to 0% (invisible); notice how we see more of the line below as the circles fill pattern becomes more transparent.

Why do the objects appear to fade to white?
In the above examples, the objects appear to fade to white because the background (in this case the PowerCADD drawing page) is white. However, if the objects below the transparent objects are colored, then the color tint will be different. Here's a simple example where the same solid blue fill object with a 40% or 20% fill opacity is overlaid on different colors and patterns. When compared to the white or black background on the far left, adjusting the objects opacity does not specifically fade to white. Rather, the color is a mix between the foreground (transparent) objects and background (opaque) objects.

While it's easy to confuse transparency and opacity, they are essentially opposite sides of the same coin. We change opacity to make something more see through, in effect making something more or less transparent. Put another way, adjusting opacity is like fading in or out. We fade in to solid, we fade out to invisible by adjusting an objects opacity.

We hope that helps

If you found this article or the website in general to be helpful, educational or a time and money saver you can show your support by buying us coffee, lunch, or dinner. Thank you ~ Brian (huc) Huculak

No votes yet