Image of NGC 3532, an open star cluster containing 120 stars, on the outskirts of the Carina nebula. It was taken from my home location with a total exposure of 32 minutes.
I’ve had ongoing problems with intermittent frame dropping and on this night I had to cut short my imaging, as no more of the 29 second still frame exposures were being received by SharpCap, amid warning dings from my laptop.
Subsequent to this I have spent a lot of time testing all my USB3 cables and found a 2m cable which transmitted frames consistently, while most did not. However, I really would like to use a longer cable and my suspicion is that the USB system in my laptop is not up to scratch. 😕
Object Details:
NGC 3532, Caldwell 91
Constellation: Carina
Visual magnitude: +3.0
Apparent size: 50′
Diameter: 23.3 light years.
Distance: 1600 light years.
Altitude: 55° above SW horizon.
Image:
Exposure: 32m 37s (67 frames 29.2s).
Gain: 128.
Date: 6th May 2019.
Location: Outer suburban.
Conditions: Mostly clear.
Sky: 1.80 e/pixel/s
Moon: no
Processing:
Image acquisition software: SharpCap, live stacked.
Image post-processing: GIMP.
Cropping: no.
Diffraction spikes: added.
Gear:
| Telescope: | SkyWatcher Esprit | Type: | 120ED triplet refractor |
| Focal: | 840 mm F/7 | Mount: | SkyWatcher EQ6-R Pro |
| Camera: | ZWO ASI 071 MC Pro | Type: | CMOS 28.4mm 16 Mpx |
| Optical aids: | Flattener: Y; filter: N | Guiding: | No |
| Polar aligning: | QHYCCD PoleMaster | Polar Error: | 04’ 05” |
Also relevant: Star Cluster Portfolio
Image © Roger Powell
Cosmic Focus 