M45, the Pleiades, is the most beautiful open cluster in the sky.

In this relatively deep image, we can see that it sits in a field strewn with faint nebulosity. The cluster is made up of more than 500 stars, with the brightest being known as the Seven Sisters.

The blue nebulosity that surrounds the cluster is a reflection nebula. It is made of fine grain dust particles that reflect the light of the nearby stars. This nebulosity is part of a larger molecular cloud which can be seen in the background of this image. The Pleiades however, were not formed out of this cloud of matter, it just happens to be passing through.

• Lens: Canon 300mm f/2.8 L USM IS telephoto lens
• F/stop: f/2.8
• Exposure: Composite of 22 frames, each 2 minutes long for a total of 44 minutes exposure
• Mount: Polar-aligned tracking equatorial mount, auto-guided
• Camera: Canon EOS 20Da DSLR
• Mode: Raw
• ISO: 1600
• White Balance: Daylight
• In-Camera Noise Reduction: Off
• Filter: IDAS LPS
• Temp: 45F
• Time 1:10 a.m. EDT
• Date September 28, 2005
• Location: Scott's Pitt, NJ
• Calibration: Darks: 16 x 10 min + bias frames to create a scalable master dark frame. Auto-dark calibrated each light frame in Images Plus v2.75beta.
• Processing: Automatic Image Set Processing in Images Plus v2.75 where all light CR2 raw files were converted to 16-bit linear TIFF files with No White Balance, Color Filter Array as the white balance type, then calibrated with the master dark. The light frames were then Bayer interpolated to convert them to color images. The light frames were then registered and aligned in Images Plus. The light frames were then composited together and "stacked" in Images Plus using min-max excluded as the method. Digital Development was then applied to this 16-bit linear TIFF master light image. The image was corrected for vignetting with GradientXTerminator. Color balance was then adjusted with levels and curves modifications in Photoshop CS2. An SMI enhancement was applied to bring out the really faint detail. Color saturation was increased and the image rotated in Photoshop CS2. Noise Ninja was used to reduce noise in the image.