NGC4565 – Edge-on Spiral Galaxy
2005 & 2021

This large spiral galaxy in Coma Berenices presents an edge-on view to us. It is between 30 and 45 million light years away.

I originally imaged this galaxy in 2005 with a long focal-length telescope, then again in 2021 with a different telescope offering a wider view. This is the 2005 image. Scroll down for the 2021 image.

2005 Image

Exposure
Luminance   8.2 hours (98 x 5 min.), binned 1x1 (56 @ -20°C, 42 @ -15°C)
Red   1.3 hours (15 x 5 min.), binned 2x2 @ -20°C
Green   1.3 hours (15 x 5 min.), binned 2x2 @ -20°C
Blue   1.4 hours (17 x 5 min.), binned 2x2 @ -20°C
Processing Dark and flat frame reduction in CCDSoft
Sigma-reject combined in MaxIm
Several iterations of levels and curves in Photoshop CS
Highpass filter and NeatImage filter in Photoshop CS
Date and Location Luminance: May 1 & 10, 2005
Color: May 2 & 3, 2005
Montpelier, Virginia, USA
Equipment Celestron 9¼" at f/10 on a Celestron CGE equatorial mount
SBIG ST-8XM camera
SBIG AO-7 adaptive optics unit
Optec IFW filter wheel with Astrodon TruBalance filters
Optec TCF-S focuser
Optec Pyxis camera rotator
Imaging and autoguiding with MaxIm DL 4

2021 Image

This view of NGC4565 was acquired during 2021-22 with a 910mm focal-length telescope, which captures a wider field than the 2,400mm scope I used in 2005. But my current camera has many more pixels than the 2005 camera, so I was able to "zoom in" by cropping away the extra area.

Exposure
 • 13¾ hours (82 x 10 minutes) @ -20°C & -15°C
 • Dusk flats
 • Camera position angle: 0°
Processing  • With PixInsight:
   ☞ Calibrate, star-align, and integrate subframes
   ☞ Background neutralization
 • Noise reduction with Topaz DeNoise AI
 • Final tweaking in Photoshop CS6
Location  • Louisa County, Virginia, USA
Dates  • 2021: May 31, June 5, June 14
 • 2022: April 19, April 22, April 24
Equipment
  • TMB-130SS APO refractor @ f/7 on an A-P 1200 mount
 • ZWO ASI-1600MC Pro color camera
 • Guided with a ZWO ASI-120M camera on a 60mm f/5 scope
 • Imaging and autoguiding with MaxIm DL 6.20
 • Automated image acquisition with ACP Observatory Control

Updated May 23, 2023