Quote:
Originally Posted by AlexN
Always the way Peter...
I agree, regarding the self guided CFW.
AO is one of the other things that really seems to have disappeared over the years, I don't understand how the concept hasn't become SUPER mainstream... ..
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As we have drifted onto this, I'm of a similar view regarding AO and my comments elsewhere might be worth repeating.
I was one of the very early Beta testers and owner of the original SBIG mirrored AO unit.
Just so we are clear and in difference to comments elsewhere, SBIG’s AO is not a “guider”.
It is indeed a first order (read: tip-tilt) adaptive optics device.
But don’t take my word for it: Hardy’s “Adaptive Optics for Astronomical Telescopes” 1998 Oxford University Press will also give that view plus sooo much more….
The natural enemy of the SBIG AO was UPS….and I’m not talking about stable power supplies…but United Parcel Service.
They were precision bits of kit that needed TLC and simply did not like being tossed about. Their journey from and assembly in San Luis Obispo to arrival at Botany Bay was similar to the First Fleet’s. Not a good one.
As a result with “my dealer hat on” I recalibrated a number of AO’s that clearly had been placed into a tumble dryer for several hours just for good measure.
Correctly re-calibrated the original AO running …wait for it… MS DOS….with say a magnitude 6 or brighter guide star can and did modulate the mirror up to 30Hz.
The seeing however had to be “slow” to really see a measured improvement with the AO in place. If the air was “boiling” better not to image with the AO or for that matter, period, on such nights.
The migration of its operating software from DOS to windows was also not a happy one. The GUI overhead slowed down AO to about 20Hz.
As the original AO was a mirrored device, optical theory tells us we got double the movement at the focal plane, for x-amount of angular tilt, compared to refractive device.
Hence no surprise that when the touchy-mirror was dumped in favor of albeit a more robust refractive Adaptive optic the maximum guiding rate dropped to about 15Hz (computers also got faster running Windoze).
As to AO not being in too many amateur hands these days, well yes that is true. I think it’s simply the cost. AO’s are expensive, but given the right conditions, can measurably improve FWHM’s.
For many however, dropping several $K dollars for an accessory that gives you 20% sharper data only on suitable nights…meh....you’d probably buy more CMOS acreage instead.
But for the OCD among us (self included) who seek imaging Nirvana….it another essential tool in your imaging arsenal.
