Friday, August 27, 2010

Halftones as you've never seen them before

I use a variety of image analysis tools when investigating how different halftone screening solutions perform. These tools are normally used in the medical field to do image analysis of microscope acquired imagery. However I press them into service to analyze various aspects of halftone dot structures.

Here is a microscope view (200x) of a conventional AM/XM printed halftone dot (175 lpi elliptical):
And here's a microscope view (also 200x) of a 20 micron FM screen:
One of my favorite tools is to use image analysis software to project the pixel density values in the images into height - creating a 3D image that shows the relative ink density (ink film thickness) differences between the two screens. The thicker AM/XM:vs the thinner FM:Using color mapping instead of the actual ink color makes the difference in ink film thickness even clearer (yellow = greatest - blue= lowest ink film density):Lowering the viewpoint and warping the perspective of the 175 lpi AM/XM screen begins to turn the image into a kind of landscape: However, using terrain mapping software on those original microscope images of the AM/XM and FM screens really makes the transformation of the images into proper landscape views a reality.

175 lpi elliptical dots:
Sunlight across a deep FM canyon:
A low flight over a a barren land where FM and AM screens meet.
Sunrise over an AM screen mesa.
Moonrise over an FM peak.
FM screen hits the wall.

Planet Round Dot.

And if you have a pair of these:
You can add a bit of dimension to your halftones:
Of course, this is all very serious work - not fun at all. Really. ;-)

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