This is not an article explaining what a dark frame is or how to take one or how to subtract it from an image. It is only to share with you a few test images I made lately (my first actually); I am not relating the two topics (i.e; dark frame subtraction with light pollution!):
No dark frame subtraction
With dark frame subtraction
This post is one of a series of short posts on the three main astroimaging techniques; scenic, afocal, and prime focus. This series is also part of a larger series on the fundamentals of astroimaging which are based on a presentation was preparing a while ago. For today I will introduce you to the first, the scenic image which you naturally take quite often. As a start here’s the definition of “scenic”:
Scenic: Of or pertaining to scenery; of the nature of scenery; theatrical [1913 Webster]
As the definition implies, such an image is one of people or anything in the foreground along with some natural scene in the background. By natural scene I mean a scene of nature; a scene with trees or mountains or land or the horizon or anything Earthly or a combination of those.
This imaging technique is a relatively easy to use as people do it all the time, naturally; all that it requires is some perception. I chose this this particular technique for this post since a very nice imaging opportunity  is coming soon which you could use to both learn this imaging technique and to take a nice astroimage with relative ease. All you need is your cam and your tripod (or use your imagination & skills to position the cam on a surface with the right angle & direction; for example you could use a table mount, or an inclined book). Continue reading