A visual phenomenon . . .

Our community does a nice job decorating for the holidays. Most of the entrances have feature huge evergreen trees that they drape with hundreds of colored lights--red, blue, green and orange.

I've noticed this in the past. Tonight, however, I did a little experiment.

When I'm at a distance from the trees, all the lights appear to be oblong, with the red and orange lights oriented vertically and the blue and green lights oriented horizontally. Moreover, the red and blue lights both appear slightly longer than the orange and green lights.

The impression is really quite stunning. But when I get up close, the aspect ratios disappear and I can see that the lights are all basically round.

The elongation is an optical illusion.

And tonight I did an experiment: I tilted my head 90 degrees to the right and, sure enough, the blue and green lights then appeared to be elongated in a vertical position and the red and orange flipped to a horizontal aspect.

--Any ideas concerning why I would see such phenomena?

Do you have that kind of experience?

Reading what shouldn't be there . . . but is

I have three or four web pages set up as my standard home pages on my web browser. But I so rarely start a new session that I almost never visit my home pages!

Today, however, I wanted to have two browser sessions going at the same time--so I could copy material more readily from one screen to another. (Just a little easier than using multiple tabs in one browser session.)

Anyway. That meant I saw my home pages--which include iGoogle--for the first time in weeks. My eye was attracted--as it usually is--to one of the widgets I have running on iGoogle: Mighty Optical Illusions.

And today's optical puzzle was a doozy:

What do all those strange shapes stand for?

I know--or at least I assume--the artist has to be playing with negative space. Normally I can "see" whatever-it-is they have hidden in the negative space. But this one just seems really difficult!

Eventually, with the help of some commenters, I was able to make it out. But unlike the editor of the blog, who says, "once you see it, there’s no going back," I will confess that I "go back" regularly. I have to almost trick myself into seeing what the artist has hidden.

See how you do.

If you can't make it out, let me suggest that you pretend you are looking at a flat piece of bright metal. Someone has cut holes in it with an acetylene torch. The metal is brightly lit from the front (behind you, over your right shoulder), and the background is dark.

Yes, it does say something.

If you don't get it, "check this revealing article," writes the blogger. And there you will find an easier puzzle of a similar variety -- although I believe we should say it uses positive rather than negative space:

Well?