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Bobbyoutback
20-10-2009, 02:00 PM
Hi ,
This is my first post & I'm a bit embarrassed that I took apart the objective lens on a ED80 to try an improve the diffraction ring patterns .

I did make a note of the original positions but lost that 2 years ago . :(

Any help would be most appreciated as I do miss using it .

Cheers
Bobby .

dpastern
20-10-2009, 02:22 PM
Welcome to IIS, I can't help as I don't have the knowledge, but hopefully someone else can.

Dave

leon
20-10-2009, 02:38 PM
Oh Dear :eyepop: Bobby, why did you do that :eyepop:

Leon :thumbsup:

renormalised
20-10-2009, 02:56 PM
Yep...the old adage, "If it ain't broke, don't fix it":D

Those lenses are arranged in that way for a purpose...each is cut and polished to produce the correct figure for each individual set of lenses, so when they are aligned, they give (almost) the textbook diffraction pattern.

Now, you're going to have to experiment until you find the right alignment for those lenses. Plus get the spacing between the lenses correct.

Baron von Richthofen
20-10-2009, 04:20 PM
They tell me it is very easy, first reassemble the lenses then look at a bright star to use to adjust the diffraction ring patterns
1 turn the outer or inner lens slowly through 360 noting where gives you the best pattern
2 turn the lens element to this position and adjust slowly for best pattern
3 turn the complete lens cell through 360 noting where gives you the best pattern
4 turn to this position and adjust slowly for best pattern
5 turn the lens element and adjust slowly for best pattern
and your dun

Bobbyoutback
20-10-2009, 07:55 PM
Thanks for the welcome & advice :)

Leon :-
I thought who-ever had first put it together didn't get it just right so I had a go & ~ whoops !

Red Baron :-
Thanks for those detailed instructions , will give it a try on the weekend , wish me luck .

If I muck it up maybe I can sell it cheap for parts :shrug:

Cheers
Bobby.

AstralTraveller
21-10-2009, 10:25 AM
Don't do that. If worst comes to worst I should be able to get someone to set it up. I would have to call in a favour and you would have to pay postage to and from Wollongong. Hopefully it won't come to that. :thumbsup:

Bobbyoutback
21-10-2009, 12:11 PM
Wow thanks David , thats a a very gracious of you :thanx:
Hope I can fix it first .
I do have other scopes but missed the little ED for its portability .

I'm a meteorite hunter & would like to send you a small H5 chondrite meteorite ~ my treat .
If you send your details I'll post it at no costs to you .

Regards
Bobby.