One Simple Infographic that explains Spatial Frequency

Hello everyone,

I am endeavoring to write shorter emails! Here is a simple infographic:



Assuming a standard viewer distance (CSS reference pixel visual angle):
a stroke width of between 8px to 20px is at the peak of contrast sensitivity, while 
a 1px stroke width drops contrast perception down an order of magnatude x2 from peak.
Increasing stroke width (by increasing font size and/or font weight) increases perceived contrast
especially closer to threshold, and
especially at the higher frequencies (over 16cpd).
impairments offset this curve, typically down and to the left.
The implication is that impairments come closer to threshold sooner, and need additional contrast
Please let me know if there are questions/comments.

I do have one question: is there a way to save graphics/attachments for emails to the list archive? I see they are always stripped? Perhaps I should just double post them to the Wiki?

Thank you!!

Andy


Andrew Somers 
Address Redacted for List