Simcoe Skies Astronomy

M101 - The Pinwheel Galaxy

M101
M101 - The Pinwheel Galaxy
This is a partial shot (need a focal reducer!)

Date: Sept 18/04
Exposures: 33 best of 61
Exposure length: 20 seconds
Amp on setting: OFF
Brightness: 100
Gain: 50
Notes: This is a BIG sucker! Image appears "noisy" because it's a high light level area (center core) of a large galaxy. Mental note to try this again with a focal reducer, eyepiece projection, or make a mosaic and get the whole thing. Reducing the gain may help to emphasize the spiral structure vs. overall brightness.

M101
M101, reduced image size
1/3 size image to illustrate better contrast overall

Date: Sept 18/04
Exposures: 33 best of 61
Exposure length: 20 seconds
Amp on setting: OFF
Brightness: 100
Gain: 50
Notes: This looks better - thus either eyepiece projection or a focal reducer would compress the image and increase the contrast (and reduce the exposure length required).

M101, July 2005
Processed with less brightness

Date: July 2/05
Exposures: 62
Exposure length: 19 seconds
Amp on setting: OFF
Brightness: 100
Gain: 50
Notes: First experiments with guiding on this one, amp glow problem solved! "Holes" in image due to hot pixel removal in K3CCDtools. Amp glow was previously showing up because I was removing the cam from the eyepiece adapter for dark frames. This changed the temperature for the dark and created a mismatch.

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	M101 - The Pinwheel Galaxy This is a partial shot (need a focal reducer!) Date: Sept 18/04 Exposures: 33 best of 61 Exposure length: 20 seconds Amp on setting: OFF Brightness: 100 Gain: 50 Notes: This is a BIG sucker! Image appears "noisy" because it's a high light level area (center core) of a large galaxy. Mental note to try this again with a focal reducer, eyepiece projection, or make a mosaic and get the whole thing. Reducing the gain may help to emphasize the spiral structure vs. overall brightness.

	M101, reduced image size 1/3 size image to illustrate better contrast overall Date: Sept 18/04 Exposures: 33 best of 61 Exposure length: 20 seconds Amp on setting: OFF Brightness: 100 Gain: 50 Notes: This looks better - thus either eyepiece projection or a focal reducer would compress the image and increase the contrast (and reduce the exposure length required).

	M101, July 2005 Processed with less brightness Date: July 2/05 Exposures: 62 Exposure length: 19 seconds Amp on setting: OFF Brightness: 100 Gain: 50 Notes: First experiments with guiding on this one, amp glow problem solved! "Holes" in image due to hot pixel removal in K3CCDtools. Amp glow was previously showing up because I was removing the cam from the eyepiece adapter for dark frames. This changed the temperature for the dark and created a mismatch.