Simcoe Skies Astronomy

M27 - The Dumbbell Nebula

General info about this object
More about Planetary Nebulae

Most recent images are at the top of this page

M27
August 2009 image - first try with Meade DSI-2C camera
Collimated, focused using a Bahtinov mask, and guided in RA

Date: August 31, 2009
Camera: Meade DSI-2C
Exposures: 120
Exposure Length: 20 seconds
Gain: 63; Offset: 0
Filters: built-in IR filter
Magnification: x1 (no barlow, no resizing)

Notes: Very pleased with this shot. The combination of guiding, focus, and good collimation all contributed to a worthwhile result. It's interesting to compare this to my FIRST shot of this 5 years ago (scroll down to the bottom). Also worth noting is the fact that the stars behind the nebula are seen through its red outer glow, whereas those closer to us show as near-white.

Dumbbell Nebula October 7/06
Oct 2006 version
A collimated image with better processing technique

Magnitude: 7.6 (surface brightness 11.47)
Size: 6.5' Location: Vulpecula
Date: Oct 7/06
Exp Details: RAW,A0;B50;GN51;GM52;R34B18;T20S
Exposures: 64 of 120
K3 Brightness Level Meter: 130-150.
Filters: Skyglow Filter
Magnification: x1 (no barlow, no resizing)

Notes: A good collimation resulted in a decent image. Lots of lessons learned since the last image 2 years ago. Stacking/processing and initial histogram adjustment in K3CCDtools. Subsequent levels adjustment in Photoshop, noise reduction with NeatImage. Stars are round (collimation) and don't have dark holes beside bright spots (camera in RAW mode). A longer exposure brought out more detail in the nebula.

M27 - previous data reprocessed
Sept 2004 data, reprocessed again in K3CCDtools

Date: Sept 2/04
Exposures: 57 of 62 hand picked
Exposure length: 12 seconds
Amp on setting: OFF
Brightness: 60%
Gain: 70%
Notes: At the sacrifice of some of the nebulosity, I adjusted the contrast in K3CCDtools histogram so that the amp glow was eliminated. Stars still have "ears" probably indicating drift from poor alignment. Color in this one is more vivid, and as always, I endeavored to keep the background stars "white" as a reference to true color.

M27 - 2nd try
Sept 2004
This was my 2nd try

Date: Sept 2/04
Exposures: 28 of 62 hand picked
Exposure length: 12 seconds
Amp on setting: OFF
Brightness: 60%
Gain: 70%
Notes: Image has too much background brightness in upper left (amp glow) - over time I discovered that this was a result of insufficient average gain/brightness/exposure combination (an inadequate darkframe, so that the "true" dark is not actually subtracted). Stars are "ears" indicating either Periodic Error in the mount, or (more likely) drift. Nevertheless, there are some nice nuances of nebulosity showing in the bottom left.

M27 - Dumbbell Nebula
M27 - Dumbbell Nebula - first light
This was one of thee shots taken on my first night out with the modified ToUcam.

Date: Aug 26/04
Exposures: not recorded
Exposure length: not recorded
Amp on setting: ON
Brightness: not recorded
Gain: not recorded
Notes: Too much blue! White balance was off, not corrected in histogram. Longer exposures needed!

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	August 2009 image - first try with Meade DSI-2C camera Collimated, focused using a Bahtinov mask, and guided in RA Date: August 31, 2009 Camera: Meade DSI-2C Exposures: 120 Exposure Length: 20 seconds Gain: 63; Offset: 0 Filters: built-in IR filter Magnification: x1 (no barlow, no resizing) Notes: Very pleased with this shot. The combination of guiding, focus, and good collimation all contributed to a worthwhile result. It's interesting to compare this to my FIRST shot of this 5 years ago (scroll down to the bottom). Also worth noting is the fact that the stars behind the nebula are seen through its red outer glow, whereas those closer to us show as near-white.

	Oct 2006 version A collimated image with better processing technique Magnitude: 7.6 (surface brightness 11.47) Size: 6.5' Location: Vulpecula Date: Oct 7/06 Exp Details: RAW,A0;B50;GN51;GM52;R34B18;T20S Exposures: 64 of 120 K3 Brightness Level Meter: 130-150. Filters: Skyglow Filter Magnification: x1 (no barlow, no resizing) Notes: A good collimation resulted in a decent image. Lots of lessons learned since the last image 2 years ago. Stacking/processing and initial histogram adjustment in K3CCDtools. Subsequent levels adjustment in Photoshop, noise reduction with NeatImage. Stars are round (collimation) and don't have dark holes beside bright spots (camera in RAW mode). A longer exposure brought out more detail in the nebula.

	Sept 2004 data, reprocessed again in K3CCDtools Date: Sept 2/04 Exposures: 57 of 62 hand picked Exposure length: 12 seconds Amp on setting: OFF Brightness: 60% Gain: 70% Notes: At the sacrifice of some of the nebulosity, I adjusted the contrast in K3CCDtools histogram so that the amp glow was eliminated. Stars still have "ears" probably indicating drift from poor alignment. Color in this one is more vivid, and as always, I endeavored to keep the background stars "white" as a reference to true color.

	Sept 2004 This was my 2nd try Date: Sept 2/04 Exposures: 28 of 62 hand picked Exposure length: 12 seconds Amp on setting: OFF Brightness: 60% Gain: 70% Notes: Image has too much background brightness in upper left (amp glow) - over time I discovered that this was a result of insufficient average gain/brightness/exposure combination (an inadequate darkframe, so that the "true" dark is not actually subtracted). Stars are "ears" indicating either Periodic Error in the mount, or (more likely) drift. Nevertheless, there are some nice nuances of nebulosity showing in the bottom left.

	M27 - Dumbbell Nebula - first light This was one of thee shots taken on my first night out with the modified ToUcam. Date: Aug 26/04 Exposures: not recorded Exposure length: not recorded Amp on setting: ON Brightness: not recorded Gain: not recorded Notes: Too much blue! White balance was off, not corrected in histogram. Longer exposures needed!