The  Holin A. Grotch Observatory

Scottsdale, Arizona



The Holin A. Grotch Observatory is an astronomical-imaging site dedicated to obtaining high quality pictures of the galaxies and nebulae in our night sky. On these pages effort is made to present these objects as the human eye would see them if only we could get close enough to them to perceive their actual shapes and colors.

 

When looking through the eyepiece of almost any amateur telescope it is rare that any color is perceived in any celestial object. That is because the human eye's rod and cone cells do not integrate the light they see (you can look at an object for a very long time and it doesn't appear to get brighter). On the other hand, a digital camera (or photographic film) will integrate the light entering it over time - the longer it "sees" the object, the brighter the image will get. That is why a "time exposure" reveals things too dim for our eyes to perceive. That is essentially the technique used here. Most of the images are the result of several hours of exposure time.

 

I hope you enjoy these images. To see them, please go to the next page.  

 

After you click on the name of any object you will see its image. There is a description of each object just below its image.

Don Scott




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