Nevay Observation

  • Likely last clear night for a while so in on Sunday
  • 18:30: coolers on (c1c:2 - -15:-20), dome open fan on with door open to cool dome down.
  • Both coolers around 75% power.
  • Clear sky, visibility good - twinkle below 30 deg alt.
  • Sunset at 8pm, aligned to Sirius by 20:20
  • Spent some time focussing both telescopes - the main telescope definitely needs realignement.

  • Recorded camera 1 cool down in 3 minute intervals for 1hr to show cooling ring.


  • Moon
  • Orion
  • Heart Nebula
  • Elephant's Trunk Nebula
  • Wizard Nebula
  • Saturn
  • Pin Wheel Galaxy narrow field LRGB


  • Few images of the moon using the widefield scope
  • Sky was still blueish and moon blinding - used H Alpha filter to reduce
  • 3 images of the moon


  • Touched up focus of widefield scope after shooting moon
  • Composed shot of orion
  • Guiding ok on star near core - main scope and wide field not aligned with each other
  • Record luminance filter, 10s, 30s and 120s in sequence x5
  • Not really sure of the best result until post processing so record a few and maybe even HDR combine.
  • Aerial in way - break for 10 mins
  • Back on - 21:20
  • 21:40 - H Alpha images
  • 120s shows some nice structure, but can easily go higher without saturating on stars
  • 400s Ha exposure.
  • 400s slightly saturated in core, but lovely detail in wings.
  • Settled on 240s - repeating 5x
  • 22:07 - on to heart


  • Difficult because of declination
  • Had to rotate camera on main scope
  • Had to pull cables out a little more as not enough length
  • Drove scope all the way round so as time progresses, cables will loosen not tighten
  • Can't use stellatrium to position!
  • Not quite aligned
  • 1800s Ha exposures and 120s L
  • 00:00 1x of each done, on 2nd 1800s.
  • Pretty cold - camera 2 cooler at -20C and only 50% power - could run harder, but wouldn't have calibration set and likely can't get one in daylight ours so stick to -20C.
  • Upped RA guiding agressiveness from 2 to 3 as it was wandering a bit.
  • 01:08 1800s exposures continue.

Elephant's Trunk

  • Moved manually as can't use stellarium as it'll loop round in RA
  • Aligned ok
  • Not shown in stellarium or clearly in astrometry so took a few tries to get in the right place
  • 10 min Ha showed up something and then realigned using the stars in both the Ha and L images.
  • It's roughly a ring but the 'trunk' is on one side so although I was aligned to the ring perfectly, I offset it to get more of the trunk in field of view.
  • 4x Ha at 30min, 9x L at 120s. In 4th Ha at 4:44
  • Decided to stick with this target rather than trying any others to get as many sub frames as possible to beat the noise.


  • Lastly 60 flats as focussed was changed.
  • 5:52.

-- LaurieNevay - 02 Apr 2017

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Topic revision: r4 - 03 Apr 2017 - LaurieNevay

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