I have two cameras, an ASI585MC and a Nikon D5100. I have been unsuccessful in getting the ASIAir Plus to work with the ASI585 on my C8 SCT in either F/10 2032mm focal length or F6.3 1280mm focal length. The main problem is the GO TO features don't work. I can get plate solving to work by setting in BIN 2 or 4 but when trying to GO TO objects ASIAIr can't find targets or gets close but can't center then decides to take off in another direction. This issue is probably due to the sensor size is too small. Minimum FOV is 0.2° x 0.2°.
I upgraded to the 2.1.2 beta but in 2.1.1 10.74 I was having GO TO issues also.
I happen to have a supposedly supported DSLR, a Nikon D5100. Its got an APS-C sensor 23.6mm x 15.6mm
is size. That should be big enough for ASIAir to plate solve and figure out where it is so GO TO will work. If my D5100 worked I was going to go ahead and purchase either a ASI294MC or ASI071MC.
I decided to test the D5100 at F/10. Accord to astronomy.tools the D5100 sensor (similar to the ASI071) has a FOV of 0.66° x 0.44°. This should be plenty of FOV. I also added spacers between the D5100 and C8 to get to 127mm which Celestron states is back focus for F/10 on an 8" SCT. I'm within 1mm. Camera with T2 adapter is 55mm. The rest is the SCT 50mm adapter and spacers of various lengths to get back focus to 127mm.
My setup process tonight was.
- Use AVX mount's polar scope for polar align.
2 Center the AVX mount to index marks
- Handset USB cable to AsiAir is not plugged in yet.
- Turn on mount. Let HC initialize to align prompt. Go through and check time, date, lat, long and make minor changes to time. Lat and long OK.
4 Power on ASIAir. Start App. Set focal length in initial data screen to 2032. Preview screen appears.
- Connect USB cable to HC. Go into APP Mount section and enable mount. Check mounts long/lat, time ad date. Time shows the same as handset. I'm in Mountain Time zone in US and on Standard Time.
- In Preview take first test image to test for focus. D5100 ISO is 400, EXP 1 sec Bin 1. Image appears and stars are focused.
- Perform Plate Solve. Fails. Incease Exp to 5 secs and plate solve succeeds. FOV shows 0.63° x 0.43° and focal length 2139mm. So focal length is no longer than 2032. Is that due to the back focus spacers to the camera?
- Start PA (Polar Alignment). Initial plate solve succeeds. Scope moves over 60 degrees. Now plate solving fails. I change the ISO to 800, Exp to 10sec. Plate solving fails.
- Quit out of PA back to preview. Use HC to go to Home position.
- In Preview, change BIN to 4. Does this work on a DSLR? Take an image and plate solve succeeds. Focal length now 2145. FOV 0.63° x 0.42°.
- Start 2nd attempt at PA. Gets through first step, rotates 60° and takes an image but Plate Solve fails again. Can't finish PA. Cancel. Go back to Preview.
- Set ISO to 1000. Take image and plate solve. Succeeds, now focal length is 2111 and FOV 0.64* x 0.42*
- Back to PA. Take image, plate solves but when ASIAir slews the scope it doesn't go over 60° more like 20° but plate solves and takes me to the manual mount adjustment routine which is completed. Back to Preview
- First Go To is Capella. Mount slews over to Capella but never can center. I have t stop it retrying. In Preview star is centered.
- Next star is Mirvak but never finds it. Slew too low almost parallel to horizon.
I powered down both mount and ASiAir and repeated the procedure but same results. Go To fails
Since I've tried two different camera my question is ASIAir compatible with SCT at F/10?
I've spent close to a month trying to get ASIAir to work with my cameras. I understand the ASi585MC may never work (Work means the GO TO feature) because of it small sensor but the D5100 should've been successful.
Are SCT in F/10 even supported bu ASIAir?
So I'm not going to buy a new camera until I find a solution to ASIAir. I may buy a mini PC and install NINA and if I get that working then sell the ASIAir. If the miniPC is not a success I'll be have a big sale of astronomy equipment.
If anyone who uses a SCT with ASiAir successfully has any suggestions please respond. I'm at a complete halt.
Thanks
