Seeing cell nuclei in the retina
Han Sibot
in the retina, by moving a pinhole in front of the eye. If you look
carefully enough you should be able to see a moving dot pattern which
is the shadow of cell nuclei, according to the investigators. A
fascinating thought! I was unable to see it myself, but I am going to
try it again. Is there someone in this newsgroup able to see this
pattern?
http://www.kyb.tuebingen.mpg.de/publications/pdfs/pdf1814.pdf
R. Wolf, A direct view on our own cone cells (2002)
Jan
Some 37 years ( yes, the ' 60 ) ago I had a very inspiriting teacher (Mr.
Koppenberg) at the Christiaan Huygens school in Rotterdam (The Netherlands)
who made himself a device with wich he could see a part of his retina.
He did this because he wants, as a part of his investigations, to now what
the possible defects were at his fovea that could causes his "lazy" eye.
As far as I can remember the device was a big wheel with nearly on the edge
a concentric ring of diaphragm's.
This big wheel was driven by a smaller one (the two connected by a snare)
wich he rotated by hand at a special speed to oscillate the diaphragm's.
Sitting with his eye in front of the circle with diaphragm's and behind the
wheel a illuminated white paper wich he looked at, he could see his own
retina in black and white.
For us, the students all of it was very exciting especially the possibility
to "see" your own fovea instead of the retina of your fellow students.
BTW, did you tried the pinhole thing after the solution you gave Olivier for
his cornea scar problem?
I am still thinking that in the way you explained it it could be possible to
see other defects "behind" the cornea more thinking about the posterior side
of the corpus vitreum that can give a "shadow" on the retina.
Jan (normally Dutch spoken)
"Han Sibot" <han...@freemail.nl> schreef in bericht
news:f4bf6279.03022...@posting.google.com...
Han Sibot
news:10463827...@halkan.kabelfoon.nl...
> Some 37 years ( yes, the ' 60 ) ago I had a very inspiring teacher (Mr.
> Koppenberg) at the Christiaan Huygens school in Rotterdam (The
> Netherlands) who made himself a device with wich he could see a part
> of his retina. He did this because he wanted, as a part of his
investigations,
> to know what the possible defects were at his fovea that could causes his
> "lazy" eye.
Inventors are inspiring and their contraptions are a joy, although currently
I am obsessed by the pinhole. I suppose the teacher's device created a
flickering field without moving shadows, so the device was probably better
in visualizing after images than retinal blood vessels.
> BTW, did you tried the pinhole thing after the solution you gave Olivier
> for his cornea scar problem? I am still thinking that in the way you
explained
> it it could be possible to see other defects "behind" the cornea more
thinking
> about the posterior side of the corpus vitreum that can give a "shadow" on
> the retina.
Last month (so before Olivier's question) I have been using the pinhole to
examine my floaters. It helped me understand their location and nature a
little.
Jan
All that I remember is the "look" at my own retina.
Maybe I described the device wrong, after all it was 37 years ago.
Jan (normally Dutch spoken)
"Han Sibot" <han...@freemail.nl> schreef in bericht
news:3e5f1038$0$23911$8fcf...@news.wanadoo.nl...
Bob S.
This is what I USUALLY-- no, ALWAYS see when I look against a bright
light background like the sky or a brightly lit ceiling, etc. It has
taken me about 3 years and more than a few minor tranquilizers to learn
to ignore this!!
Bob
Han Sibot
Those CAPITALS are so emotional that I wonder if you are referring to
ordinary floaters instead of subtle shadows of cell nuclei in the retina.
May be your floaters blocked your sight on the word "cell nuclei" in the
title, summary, and article ;-) Cell nuclei have nothing to do with
floaters. The link to Wolf's short paper is rather important, although I
recognize that it is tempting to skip links when reading postings.
----- Original Message -----
From: "Bob S."
> > I read an interesting paper that it is possible to see the cell nuclei
> > in the retina, by moving a pinhole in front of the eye. If you look
> > carefully enough you should be able to see a moving dot pattern which
> > is the shadow of cell nuclei, according to the investigators. [....]
> > http://www.kyb.tuebingen.mpg.de/publications/pdfs/pdf1814.pdf
> > R. Wolf, A direct view on our own cone cells (2002)
> This is what I USUALLY-- no, ALWAYS see when I look against a bright
> light background like the sky or a brightly lit ceiling, etc. It has
> taken me about 3 years and more than a few minor tranquilizers to learn
> to ignore this!!
"Bob S." <b...@rr.com> wrote in message news:3E60BE30...@rr.com...