Quote:
Originally Posted by gregbradley
Interesting post Allan. I notice SBIG promote the AOX as being able to do 10Mhz. Perhaps that is why its getting such good results.
I must say overall though having looked at thousands of AP images that I can usually tell the ones that use AO units. They are almost always sharper. Why that is to me is not important. They just are. If its seeing or high frequency mount corrections they seem to add something to the images. I see a similar effect when my own imaging is on a night of good seeing with excellent guiding. The images have quite a bit more detail and pop.
So I don't really see a downside here Paul. Except for the cost but to me I would consider it low risk.
Greg.
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Hi Greg,
bear in mind that the normal AO units are not operating as a nested loop.
They normally have a flip mirror & a guide star.
If the mount error takes the mirror to a certain preset angle - then
a signal is sent to the mount to correct & take the flip mirror back
to a right angle & then the AO process starts again.
The advantage of the AO is that it can correct at a much higher frequency than a mount.
I would see the real advantage is if you get a guide star that allows
for say a 10 Hz capture rate of the guide camera as most
mounts are really only able to correct at about 1 Hz &
even then they would possibly lag in performance by about a second.
If your guide star only allows for a 1 Hz capture rate then I doubt
you would see much difference in performance but I could be wrong.
There are many variables in this e.g.
what about a worm drive that causes a sudden 0.5 second spike?
- your mount wouldn't correct it but the AO would.
cheers
Allan