Quote:
Originally Posted by Atmos
It really depends on your FOV but I would imagine that if someone was to go down the path of AO they're likely to be working at a longer FL anyway. Fundimentally, multi star guiding is there to average out stellar motion across a field so as to eliminate seeing induced motion so that you're not chasing seeing. AO by definition is to actually chase seeing in and effort to counteract it which is why it needs to run many times per second.
|
clearly large FOV would not benefit from AO because there is too much variability across the field, definitely talking about sub degree FOV
Quote:
Originally Posted by billdan
Gooday Aidan,
As far as multi-star guiding goes, on Google Groups under the PHD2 forum, they have been experimenting with multi star guiding.
News is not too good, If you only had mediocre stars to guide from then multi-star was better than a single star, 20% better FHWM, however a single decent guide star was better than multi-star.
But its early days with their experiments.
Just remembered you had to use a guide scope for multi-star, cannot use OAG, not enough separation of stars
Regards
Bill
|
interesting, i haven't read about that, i will have to look into it.
Quote:
Originally Posted by Peter Ward
There has been some considerable discussion about AO's elsewhere on IIS ...so I'll be brief.
I have both an AO8 and AOX. They simply work. I have never seen them make images worse.
...but there are a couple of caveats.
You need a brightish guide star...which is much easier with the new SBIG FW-G systems...but can be tough, to nigh-impossible with NB filters on SBIG STX and legacy self guide cameras due a lack of bright guide stars (this is why the "Pros" create their own guide stars with sodium lasers...)
You also need "slow" seeing....i.e. the sort of seeing that doesn't turn airy disks into fuzzballs.
The best you can expect is around a 30% improvement in FWHM's and about the same with intensity gain.
As to whether they are worth the money?....it's rather like getting an extra inch of aperture for free (well OK, not free, but on a good night, for the cost of the AO )
As I said...I have two  |
i have read those threads, i was really wondering if there had been any updates from people who made the decision to buy AO, have they been happy with the purchase, do they no longer image without it?
it is interesting because FLI make high quality gear that a lot of people trust but they don't have AO. if it is such an advantage then why would they even be in the consideration set ?