[M]: Re: [M]Correction to last post/Difffraction focusing
| Subject: | [M]: Re: [M]Correction to last post/Difffraction focusing |
| From: | Dave Feldstein |
| Date: | Sun Jan 02 05:30:08 2000 |
Mogens:
There is an error in my response about diffraction focusing. I just
noticed you were using a refractor that doesnt have a spider so no
diffraction spikes casued by the spider. However you could easily make a
diffraction focuser for your refractor it is much more accurate than
highest pixel or hartman mask techniques. I have a spider on my scope so
I autonatically get the benefit.
Sorry for the confusion
Dave Feldstein
http://www.dfstarman.com
> Mogens Winther - Home Adress wrote:
>
> Please - concerning this Orion test image :
> http://www.amtsgym-sdbg.dk/as/ori-test/
>
> On top of this image - one may observe assymetric reflections of some
> bright stars.
>
> Does anyone know if this could be a collimation effect ? - an effect
> , which may be removed in a simple way ?
>
>
> Best wishes for the new millenia
>
> Mogens Winther
There is an error in my response about diffraction focusing. I just
noticed you were using a refractor that doesnt have a spider so no
diffraction spikes casued by the spider. However you could easily make a
diffraction focuser for your refractor it is much more accurate than
highest pixel or hartman mask techniques. I have a spider on my scope so
I autonatically get the benefit.
Sorry for the confusion
Dave Feldstein
http://www.dfstarman.com
> Mogens Winther - Home Adress wrote:
>
> Please - concerning this Orion test image :
> http://www.amtsgym-sdbg.dk/as/ori-test/
>
> On top of this image - one may observe assymetric reflections of some
> bright stars.
>
> Does anyone know if this could be a collimation effect ? - an effect
> , which may be removed in a simple way ?
>
>
> Best wishes for the new millenia
>
> Mogens Winther
