Digital BW, The Print

"Interesting comments about the variability of our perceptions of
tones > depending on what surrounds them."

An excellent demonstration Scott. I guessed as much at first seeing
the illusion but still felt compelled to open it in Photoshop and
check the tonal values for myself!

The colour demo is most interesting too. I did know that you see a 
colours opposite (complimentary) if you suddenly remove it but the 
disappearing dots was a surprise . I guess the brain hones in on the 
thing it is concentrating on and excludes other information. It's no 
wonder we are such easy prey for illusionists/magicians.

Pete

Pete.--- In DigitalBlackandWhiteThePrint@...m, Steve Kale 
<stevekale@b...> wrote:
>
> While not B&W (sorry) check out this:
> 
> http://www.patmedia.net/marklevinson/cool/cool_illusion.html
> 
> 
> > From: Scott Jones <peanutdogs@h...>
> > Reply-To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
> > Date: Tue, 01 Nov 2005 17:44:52 -0000
> > To: <DigitalBlackandWhiteThePrint@yahoogroups.com>
> > Subject: [Digital BW] re middle grey 50%
> > 
> > Interseting comments about the variability of our perceptions of 
tones
> > depending on what surrounds them. Brooks Jensen of LensWork just
> > recently spoke about this on his blog
> > 
> > http://www.lenswork.com/lwb.htm
> > 
> > And posted a really interesting picture/illustion to demonstrate 
this:
> > 
> > 
http://web.mit.edu/persci/people/adelson/checkershadow_illusion.html
> > 
> >
>