Re: Without intending offense
- From: phil-news-nospam@xxxxxxxx
- Date: 19 Feb 2006 21:21:09 GMT
On Sat, 18 Feb 2006 23:54:51 -0500 Jeff Engel <searcher623A@xxxxxxxxxxxxxxx> wrote:
| I remember a previous post where you described
| your visual experience. This time, too.I'm left
| with the impression that you might be abnormal
| in a physiologic or neurological way. Has an
| ophthalmologist heard your description? Perhaps
| there is some condition that changes your eyes'
| refractive index, spreading light into a
| prismatic range rather than focusing all colors
| to the same point. I mention neurological just
| to suggest that synthaestesia, or some such
| process, might be happening. Such drastic
| remedies as you have taken suggest that there
| would be a nameable cause for your problematic
| vision.
No simple lens is perfect over the visible spectrum. Even complex
lenses are imperfect even those they can be designed to be very
flat over the spectrum. The human eye lens, due to its small size
and close spacing to the retina, and the curvature of the retina,
can be very good. Add on corrective lenses, and things get out of
whack rather fast.
My optometrist did in fact do tests under monochromatic lights and
found there was some slight detectable differences. But under the
corrective lenses, the differences apparently would be significant.
There might be some neurological issue. But I think it is more about
the flicker than the spectra. See "autistic spectrum".
Googling for "synthaestesia" (and "synthaesthesia") didn't find
anything I could pin down what you might be thinking of for that.
Maybe you mean "synaesthesia"? I don't seem to have that. I do
like the music of the group of that name. Start here for samples:
http://www.frontlineassembly.com/discography.html
I suggest "Natural Force", track 5 of "Ephemeral".
I think the issue is more about the corrective lenses than about my
own eyes. At the edges of the lenses, not only is there a difference
in size of different colors, but a different offset as well. At the
optical center, all the colors center up quite well, but the sizes
still cause problems. And I cannot keep moving my head around to
keep the point I view in the optical center axis.
What I know is that doing any task requiring close visual work under
fluorescent lighting is stressful, even if the lighting is such that
I cannot see any flicker. For years I thought it was the flicker.
And the flicker is annoying. But I have found that even under white
LEDs power by battery sources, I have the same problem. There is no
flicker there. But there is a non-continuous spectra.
Interestingly, I have found that under the peachy glow of HPS, it is
not much of a problem. The green and red are apparently close enough
that the edges are not far apart, and the blue component is so short
in wavelength that it is just simply out of focus entirely and has no
effect. When I look at an HPS lamp at a distance, I see orange in the
center and a fuzzy ring of blue around it. The bluer MH lights are
about the same as fluorescent for me (though actually find the color
of some of them more pleasing than any fluorescent I have ever seen).
I first saw this when I had several fresh water fish aquariums, all
with fluorescent lights. But I wrote it off as just spectral issues
with the glass and angle of view. But I could very clearly see colors
at edges of everything when I looked into the tank. I did use the
special bulbs for plant growth, so there was more red/blue and less
green (they had a somewhat pinkish glow), which surely exacerbated the
issue.
Nevertheless, I have already made the decision that I will in all ways
that I can, minimize fluorescent lighting in my home (at least for what
I need to use for myself), and find other ways to increase the efficiency.
As I live in a more northern climate, there will be at least a few months
of the year in which excess heat that incandescent lamps emit can still
be usable. In addition to the spectral issues, the flicker bothers me as
well. I've seen some lights with no flicker, but that doesn't seem to be
anywhere near a common thing, yet. Maybe that's because electronic
ballasts are still not trying to get rid of the 120 zero crossings per
second.
--
-----------------------------------------------------------------------------
| Phil Howard KA9WGN | http://linuxhomepage.com/ http://ham.org/ |
| (first name) at ipal.net | http://phil.ipal.org/ http://ka9wgn.ham.org/ |
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