2017 July 29 ~ The Constellation Cassiopeia [WITH LABELS]

******************************************************************************

Photographed at Algonquin Provincial Park, Ontario, Canada, between 03.47 and 03.59 EDT

(285 km by road north of Toronto)

* Temperature 10° C.

 

* Total exposure time: 6 minutes

* 90 mm lens

___________________________________________

 

Description:

 

The familiar "W" shape of the constellation Cassiopeia rises in the north-eastern sky after midnight in mid-summer in the northern hemisphere. The Milky Way galaxy runs through this part of the sky. Many open clusters of stars, loosely bound together gravitationally, also populate this area of the sky.

 

Many dark tendrils of foreground gas obscure the light of the stars beyond in this view.

 

For a version of this image withOUT labels, click on the LEFT side of your screen, or click here:

www.flickr.com/photos/97587627@N06/36158810952

___________________________________________

 

Technical information:

 

Nikkor AF-S 70-200 mm f/2.8 G ED VRII lens on Nikon D810a camera body, mounted on Astrophysics 1100GTO equatorial mount with a Kirk Enterprises ball head

 

Six stacked frames; each frame:

90 mm focal length

ISO 3200; 1 minute exposure at f/4.5; unguided

(with LENR - long exposure noise reduction)

 

Subframes registered in RegiStar;

Stacked and processed in Photoshop CS6 (brightness, contrast, levels, colour balance)

******************************************************************************

Done