Re: [M]: LX200: Optics Question-reply
| Subject: | Re: [M]: LX200: Optics Question-reply |
| From: | John W Downs |
| Date: | Sun Sep 21 09:27:01 1997 |
As Ric forgot to include, the ring around stars because of SCT designed
optics can be removed with a filter but dont worry about it being off
centered, you cant make that assumption unless the star is perfectly
centered.
downs
On Sun, 21 Sep 1997 10:59:04 -0500 Tom Mote writes:
>Ric L Ecker wrote:
>>
>> All SCTs have it. Take a picture in bright sunlight of a cars
>chrome
>> bumber, you will get donuts instead of flairs. A refractor will
>show
>> flairs of a chrome bumber. You cant get remove it, Its cause
>because
>> SCTs use a secondary and refractores dont............
>>
>> ric http://members.aol.com/rlecker/ric.html
>> drift align. focus adjustment etc
>> Curator of the Willard Observatory.....
>
>Ric,
>
>The "Off center halo" that I described was not just an out of focus
>donut and both scopes were carefully collimated by Sheldon, the
>Meade Rep. He also tried several other remedies before arranging
>to have both scopes returned to Meade.
>
>Tom
>
optics can be removed with a filter but dont worry about it being off
centered, you cant make that assumption unless the star is perfectly
centered.
downs
On Sun, 21 Sep 1997 10:59:04 -0500 Tom Mote
>Ric L Ecker wrote:
>>
>> All SCTs have it. Take a picture in bright sunlight of a cars
>chrome
>> bumber, you will get donuts instead of flairs. A refractor will
>show
>> flairs of a chrome bumber. You cant get remove it, Its cause
>because
>> SCTs use a secondary and refractores dont............
>>
>> ric http://members.aol.com/rlecker/ric.html
>> drift align. focus adjustment etc
>> Curator of the Willard Observatory.....
>
>Ric,
>
>The "Off center halo" that I described was not just an out of focus
>donut and both scopes were carefully collimated by Sheldon, the
>Meade Rep. He also tried several other remedies before arranging
>to have both scopes returned to Meade.
>
>Tom
>
