Astrophotography is a great hobby, but it is generally considered to be difficult, expensive and time consuming. In this book I describe my way to overcome these problems. The benefit of open source software is not only the reduction of the financial burden. It also facilitates the implementation of the hobby by a variety of software tools that are easy to install and a useful remedy for the problems in astrophotography. I use UBUNTU Linux and all the examples in this book use the software on this operating system. The software is platform independent (except fotoxx) and runs as well on Windows or Mac. The focus of the hardware, which is described in this book, is also located in the low-cost area. A digital SLR or a mirrorless system camera is enough to start with. Important is the option of interchangeable lenses, especially that of a T2 adapter. No further adaptation is needed. The camera is mounted on the focuser of the telescope using the T2 adapter. In case you don't have a system camera with interchangeable lenses, a normal digital camera will do. In this case you might want to use a "digital mount," which holds the camera in front of the eyepiece. Which telescope you want to use depends on your wallet. For getting started in astrophotography, you can safely use an inexpensive achromatic refractor telescope. If necessary this can be later used as a guide scope. The telescope with a camera must finally be fixed on on a tripod or better on an equatorial mount. At this point, it becomes expensive: Even beginners should prefer a stable equatorial mount before a cheap "wobble mount." If you give up the hobby, a GOTO mount is easily sold on eBay. After this introduction, I hope you will enjoy reading the book, have a lot of success with the implementation of the content and a lot of satisfaction when looking at the results. One note to my language skills: This book is the translation of my German language book "OpenSource Astrophotografie 2.0." I apologize for any translation errors. Karl Sarnow December 2012 In the meantime, the German language version made an upgrade to version 2.2, motivated by the inclusion of more OpenSource software: The INDI-Interface for connecting a mount with a computer. The gphoto2-software to control your DSLR by your computer. The darktable-software, basing upon gphoto2. The RawTherapee-software, which allows the development of images from the camera sensors raw image. This version of the eBook brings the upgrade to the English language version. Karl Sarnow July 2013"