Here is the summary of the online course available in French and English:
 
1) Optical equipment in detail
- The focal length of an optical instrument
- The different kinds of refracting and reflecting instruments (telescopes)
 
2) Which optical instrument for which type of astronomy?
- Planetary astrophotography
- Deep sky astrophotography
- Astrophotography of the Milky Way and star trails
 
3) Summary of the different characteristics of optical instruments
- Separating power, collector, f/d ratio, weight, peaks, etc...
- Choose your telescope according to its mount (and vice versa)
- Overviews and advice on the different models of optical instruments existing on the markets (refractors and reflectors)
- Most famous resellers
 
That's it, you wanted to get started but you are lost in the multitude of different telescopes and telescopes? You don't know which optical instrument is best suited to your project? So this lesson n°2 dedicated to the first purchase of a telescope or a telescope is intended for you.
 
Thanks to its 45 minutes of videos and its PDF support to download at home, making an intelligent, responsible and profitable choice becomes very easy.
 
We approach the different types of optical instruments, Newton, telescope, Cassegrain, Ritchey-Chrétien through their focal lengths and f/d ratios. Indeed, there are a multitude of telescopes and it is important to know them in order to navigate this enormous quantity of offers. Secondly, we link the optical instruments with the types of astrophotography for which they are intended. Not all of them have the same usefulness and it is necessary to understand their properties in order to subsequently be able to meet your desires according to your needs. Finally, we talk about the characteristics that must be taken into account when purchasing to make an intelligent choice and the implications that each instrument induces regarding the mount that will subsequently have to support it.
 
Do you want to put all the chances on your side to make your first purchase successful? So let's go ! We offer you a lesson in pdf format as well as a video of three sections in which we explain everything you want to know.
 
Leave us a few words on our contact page or at the email address contact@astrophotographieonline.com and we will be happy to guide you on the path to astrophotography.