Christmas Tree Cluster in Monoceros [Explored #84]

A complex region of glowing HII ions, dark nebulae, open clusters and reflection nebulae in Monoceros. My favourite part is the Cone nebula which is easy to spot.

 

 

Technical Card

480/80mm f/6 Altair Starwave triplet refractor.

Altair Planostar 1.0 x FF with 2 inch L-eNhance filter

ZWO ASI2600MC; 44 x 360 second subs, Gain 100, Offset 25, Temp = -15c.

 

EQ6 R mount . EQMOD control. Primalucelab Sesto Senso electronic focuser.

 

Session control; SharpCap 4.1 on miniPC attached to scope. Ethernet cable to home network.

Automated plate solving GOTO.

 

 

20 dark frames

61 flat frames (electroluminescent panel A, 6500ms exposure @ 0 gain).

 

Post processed in PixInsight 1.8.9.

 

Light Pollution and Weather:

SQM (L) not recorded - 60% Moon

Clear throughout. Session ended when target reached roof level.

 

Polar Alignment:

Still adjusting to my new mount - guiding not as good as I would wish:

Error measured by PHD2= 1 arc minute.

RA drift + 0.95 arcsec/min

Dec drift + 0.27 arcsec/min

 

Guiding:

PHD2 guiding with ZWO ASI290mm/Altair Starwave 206/50mm guider. Every 8th sub dithered.

RA RMS error 1.1 arcsec

Dec RMS error 0.76 arcsec

 

Astrometry

Resolution: 1.609 arcsec/px

Observation start time ... 2025-02-05 20:40:55 UTC

Observation end time ..... 2025-02-06 02:04:24 UTC

Focal distance ........... 481.86 mm

Pixel size ............... 3.76 um

Field of view ............ 2d 47' 36.2" x 1d 52' 1.3"

Image centre ............. RA: 6 41 00.659 Dec: +9 53 45.22

Done