Saturday, August 15, 2009

Dumbbell M27 and QHY8 CCD Camera

In May 2009 I became interested in taking a next step in CCD imaging and this would involve a new camera. To date I have been using the Canon 10D for astrophotography.

Camera QHY8

I compared the QHY8, Deep Sky Imager Pro III, and the Orion StarShoot Pro Deep Space Color CCD Camera and decided to try the QHY8 CCD.
The QHY8 uses a 23.7 x 15.7 mm APS-sized 6.1 Meg-pixel Sony Super HAD CCD and has an integrated Peltier Cooler which is stated to cool the CCD to 40degrees C below ambient. This camera is a single shot colour camera. The absence of a IR filter found in consumer DSLRs makes this camera a better choice for many astronomical objects. Ha sensitivity of (QE=50%) allows for Ha nebula imaging.
A review of this camera is at http://www.stark-labs.com/craig/articles/assets/CCDLabs_ATT.pdf
The manufacturer's discussion group is at http://www.qhyccd.com/ccdbbs/
I purchased the camera from the very helpful folks at http://www.kwtelescope.com/QHY_8.htm



Some of the specifications.
  • Total pixel: 3110 x 2030
  • Active pixels: 3032 x 2016
  • Pixel Size: 7.8um x 7.8um square
  • Colour method: RGB BAYER film on CCD
  • Effective sensor area: 28.4 mm diagonal
  • Readout noise: 8-12 e @600 Kpixel/s
  • QE: 60% at green (Peak), 50% at blue and H-alpha
  • Microlensing on chip
  • Progressive Scan
  • ABG: -110dB
  • 16bit ADC with CDS and Preamp
  • USB2.0 High Speed interface
  • T-thread mounting
  • Rugged custom-fit carrying case
  • Includes both AC and 12v DC adapters
  • Dimensions: 3.5" x 3.5" x 2.25"
  • Weight: 1.2 lbs.(0.55 kg)
Second Light

Although this is not my first light image for this camera, it is my first dark site image.

Object: M27

From SEDS info http://www.seds.org/messier/M/m027.html

The Dumbbell Nebula Messier 27 (M27, NGC 6853) is perhaps the finest planetary nebula in the sky, and was the first planetary nebula ever discovered.

On July 12, 1764, Charles Messier discovered this new and fascinating class of objects, and describes this one as an oval nebula without stars. The name "Dumb-bell" goes back to the description by John Herschel, who also compared it to a "double-headed shot."

This planetary nebula is certainly the most impressive object of its kind in the sky, as the angular diameter of the luminous body is nearly 6 arc minutes, with a faint halo extending out to over 15', half the apparent diameter of the Moon (Millikan 1974).




Field Details
Date/Location: Saturday August 15, 2009, 12:20am at Moose Creek Ontario
Instrument: QHY8, through Celestron SCT C11 w/o Focal Reduction
Filters: None
Mount: Celestron CGE
Focal Ratio: Imaging at f/10, guiding at f/4.3
Guiding: Auto through William Optics Megres 90mm w/ Meade DSI and f/6.3 FR
Conditions: Visually clear with moderate humidity
Weather: 20 deg. C
Exposure: 50 minutes total in 10 x 5 min exposures (Gain 0 Offset 55)
Focusing: Imaging with Stark Labs Nebulosity 2.0 (HFR 2.0 typical)
Image Capture Imaging with Stark Labs Nebulosity 2.0 (10 exposures taken)
Autoguiding Stark Labs PDH

Exposure Details and Processing
Stacking: 9 of 10
Pixel Math: Zero Mean applied
Levels/Stretch: Levels (0, 970, 1.46)
Binning: 2x2 Adaptive


Overall impression
Compared to the 10D camera it is clear that the QHY8 is capable of recording those superb reds that make so many celestial objects beautiful. Not needing darks is also a big advantage and makes the evening out run quickly.

Thanks for dropping by.
Adrien

No comments: