Overtime: Halftones as you've never seen them before

gordo

Well-known member
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, for example, is a microscope view (200x) of a conventional AM/XM printed halftone dot (175 lpi elliptical):

175 lpi sm.jpg


And here's a microscope view (also 200x) of a 20 micron FM screen:

FMsm.jpg


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:

Surface_Plot_of_175 base.jpg


vs the thinner FM:

Surface_Plot_of_FM.jpg


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):

AM fire.jpg

FM fire.jpg


Lowering the viewpoint and warping the perspective of the 175 lpi AM/XM screen begins to turn the image into a kind of hilly landscape of peaks and valleys:

Surface_Plot_of_175 original drama.jpg


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:

175 lpi field.jpg


Sunlight across a deep FM canyon:

Land 5.jpg


A low flight over a a barren land where FM and AM screens meet:

Screen blend.jpg


Sunrise over an AM screen mesa:

Misty alt2.jpg


Moonrise over an FM peak:

Moonrise.jpg


FM screen hits the AM wall.

Great wall.jpg


Planet Round Dot:

New dot mount.jpg


Of course, this is all very serious work - not fun at all. Really, honest. ;-)
 
I used a very early version of Terrain 3d as well as the ImageJ application.
Similar. I used to play with Bryce. Also Poser. Even now when I see a nice sunset I'll think to myself; 'Looks just like something out of Bryce.' : )
 

PressWise

A 30-day Fix for Managed Chaos

As any print professional knows, printing can be managed chaos. Software that solves multiple problems and provides measurable and monetizable value has a direct impact on the bottom-line.

“We reduced order entry costs by about 40%.” Significant savings in a shop that turns about 500 jobs a month.


Learn how…….

   
Back
Top