Let me know about the FITS header stuff. That seems like a good piece of functionality to retain.
OK, a little more info after some "live fire" exercises ... basically testing focusing, having both SGP and Voyager flit around like angry hummingbirds from spot to spot focusing on things; I was trying to compare the different algo's that they use against "real world" clouds. One "advantage" of having a telescope "farm" is that I can task one for SGP, one for Voyager VCurve, one for Voyager LocalField, one for Voyager FocusMax and one for Maxim using FocusMax (yes, I know that Voyager just passes through Maxim FocusMax and regular FocusMax but you always test permuations ... you might find something!). The experiment is for all of them to go the same position which Stellarium shows as having a reasonable starfield and try to get a focus; that will tell me which is most consistent, which gets the best focus and which can survive a cloud in the middle :/
I picked about 100 locations in a cone about 30deg from vertical (again, I'm just getting focus rather than actual objects so I'm OK with just a few stars in the picture) and about 30 locations in "tough" spots with more airmass as well as before/ after astronomical twilight/ dawn to see how it does with atmospheric dispersal issues as well as stellar extinction issues from skyfog (I don't image less than 30deg below the horizon, so I didn't test that). Cameras are all identical and cooled the same value, darks were available if asked for by the app as well as exposure times the app wanted to use, and the location slews were all synchronized every 5 minutes (that was trivial with Voyager with it's DragScript, mind-numbingly tedious using SGP's and Maxim's "one at at time" sequences ... oy vey!! I guess that they expect that once you've imaged one then you're done ...)
Results were judged based both on PI calculated FWHD's from star(s) in the field center of the lights for point focusing algorithms and both CCD Inspector collimation reports plus PI FWHD's for field focusing algo's (recall that the focus point is just that, a point on a curve that is intersected by the flat focal plane/ sensor plate. If you focus only on a spot right in the center then everything else will be progressively out of focus from that spot, if you focus on the field than other than a ring of perfect focus everything else will be progressively fuzzy) Both algo's have value: if I'm shooting a galaxy that's only arc-seconds wide then I want a spot focusing algo, if I'm shooting a nebula that's many arc-minutes wide I want a field focusing algo.
Results were NOT judged on how long it took to focus ... being able to focus in seconds is meaningless if the light isn't razor sharp; I don't mind if it takes 5min to focus if my 20min exposure is going to be "pixel peeper" sharp and with my ASI 183MM and C14 I can get .14"/pixel so I will see if it's not focused!
Observations were carried out over two nights from 20:00 to 06:00 with variable high clouds (normally I try to avoid them, now I wanted to get them!) to get the twilight "tough times" as well as cloud effects. OTA's were "hot tubes" with calculated seeing at 1.5 arc-sec and SQM's varied from 19.2 to 20.5 (twilights to best), camera's were NightScape 10100's with a KAI 10100 chip
So, without further ado ...
Point Focus Algo's:
Best FWHM result: Maxim FocusMax, then Voyager FocusMax, then Voyager VCurve ... Voyager was pretty close, but about 30% of the time it chose stars to focus on that might not have been the best choice; FocusMax consistently picked the right magnitude. Both were good not to slew TOO far away from the target location for the focus star (you don't want to go more than 10deg DEC from the target because airmass will throw off the focus, Voyager sometimes roamed a bit far afield which showed on the target lights ...)
Best "cloud" result: Voyager VCurve, then Maxim FocusMax, then Voyager FocusMax ... Voyager consistently got a good curve despite clouds occluding things, FocusMax gave up most of the time (sigh)
Field Focus Algo's:
Best FWHM result: Voyager LocalField, then SGP ... both were consistent and not having to slew around saved time, but SGP sometimes gave REALLY whacky curves (I don't think they are balancing based on stellar magnitudes, which means if you're exposing long enough to get the dimmer stars you're going to be bloating the brighter one and need to take that into account when you're calculating VCurves)
Best "cloud" result: Voyager LocalField, then SGP ... SGP *really* doesn't like clouds in a portion of the field, likely a result of the bright/ dim thing for the FWHM results
One really nice thing about Voyager versus SGP is that I *can* pick what I want to use; SGP is either "in" or "out" ... additional kudo's for the DragScript, that's REALLY useful!
CliffNotes result: Voyager is a clear winner over SGP both in point focus objects (VCurve) and field focus objects (LocalField) in terms of dealing with clouds; it consistently gave me a usable focus value. For actual focus precision FocusMax natively though Voyager is the winner for point objects (galaxies), Voyager LocalField is the winner for field objects (nebulae). Therefore, when I'm planning my night if there are clouds possible I'll choose Voyager VCurve/ LocalField, if it's going to be clear and I'm shooting galaxies I'll use Voyager FocusMax and shooting nebulae Voyager LocalField ...
And now, back to my thermal mass/ mirror peltier cooling experiments ... :/ It was actually 'kinda nice watching the scopes flit around, like the fountains at the Bellagio ...
Edited by choward94002, 07 December 2018 - 01:25 PM.