Partial Transparency Pixels

Layers and graphics have partially transparent pixels on their edges to soften the edge appearance. They appear when you create a exact sized layers placed side-by-side. For instance, suppose you add a 1280×720 layer to a widescreen (1280×720 pixel screen; 16:9 aspect). Its scale is set to “fit to frame,” “fill frame,” or “stretch to frame,” sized it to 50%, and placed in the upper left corner (-25,-25). Now, duplicate it, and place it in the upper right (25,-25). You’ll probably see a thin vertical black line at the upper half of the screen center. That line is the partially transparent pixels at the edge of both layers. You may experience this condition with either a Producer generated layer or a graphic.

To reduce or eliminate this line, you’ll need to create an overlap by one or both layers. There are a number of different ways to do that.

For Producer/Graphic Layers. You could:

  • increase the layer zoom by 0.10 to 0.20 (in the zoom-x and zoom-y boxes or an equivalent amount using a constant modifier)
  • increase the physical dimensions of the layer by about 1% (so instead of a 1280×720 you would use a 1293×727 layer).
  • add an outline to the layer of 1 or 2 (only if the layer is a full layer and not a one with transparent sections along the outer side(s))

Graphic Layers. During the creation of graphics that you want to use as masks. Assuming you’re using a graphic of a specific aspect that will have a colored portion that will act as the mask while the rest of the graphic remains transparent (for instance, a 1600:900 graphic which will have a “mask” region sized at 800×450 and located in one of the four corners). When the colored area is created you could:

  • (Photoshop) Expand the filling option for the layer with a value of 1 or more.
  • (PhotoPaint) Change the size of the object by a few pixels (maybe 0.5% of the object).
  • (CorelDraw) Add a border of a few pixels (between 1 and 5 perhaps) to the object.

The effective result is that the mask region (colored portion of the graphic) is slightly increased in size by being forced to stay within the frame. So, when 2 or more of these are aligned to each other, the transparent region is either above or below a solid portion of the layer and so you can’t see it.

20110423-1254 © Dale Fenimore, All Rights Reserved
140524-2300

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