Taken on the night of 4/5th February 2023 over a 2 hour period. 144 x 30 second exposures were taken (some breaks for cloud) and every 4th exposure selected for stacking. The session was run over the full Moon which has probably obscured some fine detail.
Longer exposures caused unacceptable blurring of the comet nucleus so I upped the gain to 160 and used short 30s exposures.
PixInsight’s Comet Alignment tool tells me that the comet nucleus moves by:
-441.52 pixels per hour in the X-axis
322.46 pixels per hour in the Y-axis.
Since I know the scale of this image, I can convert that to arcminutes per hour
-11.9 arcminutes per hour
8.7 arcminutes per hour
For reference, the Moon is 30 arcminutes across.
Technical Card:
480/80mm f/6 Altair Starwave triplet refractor.
Altair Planostar 1.0 x FF with 2 inch IDAS LPS P3 filter
ZWO ASI2600MC; 36/144 x 30 second subs, Gain 160, Offset 25, Temp = -15c.
EQ6 pro mount with Rowan belt drives. EQMOD control. Primalucelab Sesto Senso electronic focuser.
Automated FWHM multistar focusing.
Automated plate solving GOTO.
Session control; SharpCap 4.0 on laptop with WiFi link to IPad.
50 dark frames
60 flat frames (electroluminescent panel, 1600ms exposure @ 0 gain).
Post processed in PixInsight 1.8.9.
Light Pollution and Weather:
SQM (L) not recorded – full Moon
Session ended by cloud, occasional cloud caused a few lost subs.
Polar Alignment:
QHY Polemaster alignment –
Error measured by PHD2= 0.7 arc minute.
RA drift + 1.41 arcsec/min
Dec drift – 0.19 arcsec/min
Guiding:
PHD2 guiding with ZWO ASI290mm/Altair Starwave 206/50mm guider. Every 9th sub dithered.
RA RMS error 0.79 arcsec
Dec RMS error 0.71 arcsec
Astrometry:
Focal distance: 480.77 mm
Pixel size: 3.76 um
Resolution: 1.613 arcsec/px
Field of view: 1d 2′ 49.9" x 42′ 49.7"
Image centre: RA: 5 17 13.301 Dec: +52 05 31.94
Posted by john.purvis on 2023-02-06 11:04:48
Tagged: , Comet , C/2022 E3 (ZTF) , Astrophotography
Leave a Reply