placing of the eyepiecelens after cleaning ?

Hello,
I know it's very stupid, but i have cleaned my eyepiece lenses and now
i know on wich side of the eyepiece they came from, but i didnt
exactly how the where positioned

The lenses have one flat side and one curved side as seen on this
pictu
http://members.home.nl/hotze.b/eyepiece.jpg

Can someone tell me how i must place the lenses ? (on wich side the
curve or convex side) ?

Thanks very much in advance
Harry

I know it's very stupid.

Yah, no argument there.

Were your eyepieces so dirty that you had to disassemble them?

Unless they are badly soiled you should never take them completely apart.

Of course, you realize this by now!!

I don't know enough about optics to help you, but hang on and someone will
soon be here to help you.

AGS

Can someone tell me how i must place the lenses ? (on wich side the
curve or convex side) ?

Thanks very much in advance
Harry

I have made this same mistake a time or two. It is not always so obvious which
way everything goes back together but with a bit of experimentation I have been
able to put them back as they were.

jon

Harry wrote in message . ..
Hello,
I know it's very stupid, but i have cleaned my eyepiece lenses and now
i know on wich side of the eyepiece they came from, but i didnt
exactly how the where positioned

The lenses have one flat side and one curved side as seen on this
pictu
http://members.home.nl/hotze.b/eyepiece.jpg

Can someone tell me how i must place the lenses ? (on wich side the
curve or convex side) ?

Thanks very much in advance
Harry
What kind of eyepiece was it? If both lenses are simple lenses of similar size and
focal length as your drawing seems to indicate, it is probably a Ramsden eyepiece
and should be reassembled with the curved sides of the lenses facing one another.
If you don't know what kind of eyepiece it was, the scope it came from might help,
ie, was it an inexpensive small refractor, in which case it probably was a Ramsden.
Clif

On Thu, 20 May 2004 12:55:38 GMT, "elsancho"
wrote:

I know it's very stupid.

Yah, no argument there.

Were your eyepieces so dirty that you had to disassemble them?

Unless they are badly soiled you should never take them completely apart.

Of course, you realize this by now!!

I don't know enough about optics to help you, but hang on and someone will
soon be here to help you.

AGS

It was a 40mm meade. I didn't used it a long time. But now i
experimented with pictures of the sun. Then i saw lots, to many ;-) of
black spots on the picture of the sun, like this:
http://members.home.nl/hotze.b/sun.jpg
When i turned the eyepiece a bit, the dots also turned, so i decided
to clean the lenses......

Thanks, Harry

Hi Harry,

It's hard to tell from the drawing. If they are truly simple plano-convex
lenses, I can think of two orientations. But with two lenses in two
positions with two choices for orientation, you have 8 possibilities. I
suspect one is larger in diameter than the other, which limits it to 4
possibilities. This may sound silly, but put it together and if it works the
same, great. If not, take it back apart and try again. You'll get it quickly
and feel smarter for having worked it out.

And don't worry about it. You are not the first person to do this. Hang in
there and let us know when you get it!

Clear Skies

Chuck Taylor
Do you observe the moon?
Try http://groups.yahoo.com/group/lunar-observing/
And the Lunar Picture of the Day http://www.lpod.org/
************************************

"Harry" wrote in message
...
Hello,
I know it's very stupid, but i have cleaned my eyepiece lenses and now
i know on wich side of the eyepiece they came from, but i didnt
exactly how the where positioned

The lenses have one flat side and one curved side as seen on this
pictu
http://members.home.nl/hotze.b/eyepiece.jpg

Can someone tell me how i must place the lenses ? (on wich side the
curve or convex side) ?

Thanks very much in advance
Harry

I
suspect one is larger in diameter than the other, which limits it to 4
possibilities. This may sound silly, but put it together and if it works the
same, great. If not, take it back apart and try again. You'll get it quickly
and feel smarter for having worked it out.

This is what I have done in the past. My guess is that this is probably a 4
element eyepiece with 2 sets of 2 cemented elements, similar to a Plossl.

It is my limited experience that in such eyepieces the similar faces face each
other so that also reduces the choices by a factor of two.

jon