Ad Astra Observatory

Art Morton wrote:
> J,

>
> You have this issue. Maybe this is the nature of the beast. I have
> sent you my FWHM and they seem to approach the best seeing
> for aperture. Maybe 8”s is just to big to allow small numbers because
> of turbulence. I wonder what you would get with AO as a part of the
> image train?

Veronica + DSLR = ~1.6”/px
I haven’t done the Airy disc calculation to determine the minimum size
of an Airy disk.
I figure that any object that doesn’t cover as many as 300px (that’s 10%
of the chip’s width) on the chip is going to be too small to really get
any useful detail. That’s 480” (8′).

In any case, that’s on the imaging side, where FWHM applies to “how good
is your focus”. On the guiding side, I’m using the ST-4 with the 66,
that’s getting something more like 7”/px. On the one hand, this could
mean that the guider is allowing enough drift for the main camera to be
noticeably off. On the other hand, what I notice is that there is a

steady drift across several images. I am convinced that I have a bad
polar alignment, but I can’t find it. It’s very irritating.

Best,
Jimbo
>
>
> A
>

> Begin forwarded message:
>
>>
>> The theoretical limit for the VC200L is going to be >1.1 arcsec.
>> Allowing for collimation reality 3” sounds great
>>