Astro-Tutorials #1: Theory

#1.1: „What is there to see in the night sky?“

The first part of episode 1.1: „What is there to see in the night sky?“ covering the Solar System Objects
Part two of episode 1.1: „What is there to see in the night sky?“ covering the Deep Sky Objects we can observe from our backyard

#1.2: A brief orientation in the night sky“

On your first night under dark skies everything might seem a bit overwhelming and even intimidating. Download Stellarium, a free planetarium software, to get to know the night sky. The more you stroll around the night sky, the more it will get used to you.

#1.3: „How to use Stellarium?“

A short rundown on how to use the planetarium software „Stellarium“. This piece of software is essential for you, believe me! You get to know the stars, their path in the night sky, plan your sessions, control your mount!

#1.4: „Coordinate Systems of the night sky“

We use “Stellarium” to explore different aspects of the grids that help us to orientate in the night sky.

#1.5: „Focal length and Aperture“

We will find answers about scope specs and talk about: – optical resolution – the field of view or – the light gathering capabilities of scopes.
And then, if you are used to all of this terms, you can start to decide what scope might fit you best.

#1.6: THE F-RATIO „fast“ vs „slow“ scopes

This time we want to bring this two units together and see what scopes we can possibly create. Discover “fast” and “slow” scoped of different kinds from the cheap lens scope to visit the moon right to the cutting edge “astrographs” like the RASA11 from Celestron.

#1.7: Types of Telescopes

this time we want to open up the telescopes to look what’s inside. We will discover different types of telescopes – some with lenses, some with mirrors or even some with both of it. What is an apochromatic Refractor? How does a Newtonian Reflector work? Lets find out! Clear skies everyone and have fun!

#1.8: Science behind telescopes – field curvature, coma corrector and light paths

– Are all light beams from the same star? – What is field curvature? – Why are stars at the image edges always blurred? – Why can’t I see the secondary mirror in my final image? – …

#1.9: Telescopes, Eyepieces & Magnification

We will cover different topics: * the underlying principles of eyepieces * the light paths inside eyepieces * the magnification * limits of the magnification * different types of eyepieces

#1.10: Night Sky, Star Trails & Tracking

No matter whether you choose a simple tripod and a DSLR or a small tracking mount, or the sturdy and heavy tracking mounts for DSOs. You should know the basic vocabularies and how everything connects with things like: x star movement x focal length x exposure time x polar alignment and tracking.

#1.11: Telescope Mounts – ALT/AZ vs EQ

A proper and solid mount – capable of carrying your scope with ease – will not only be useful. It will be essential to your ongoing journey to the skies. Never underestimate that. You might have bought a good optic on top. But if your mount can’t serve it well, every image will be lost and no data can be acquired. So: prioritize the mount over the optic!

#1.12: What is „seeing“?

What factors influence our observation session? How do different seeing conditions look like? We will discuss this topics by having a look at three images I took from Venus. One with bad seeing – one with intermediate seeing and one with quite good seeing.

#1.16: Deep Sky vs Planetary Imaging

Hey folks, today we want to compare two subtopics of astronomy: Deep Sky Imaging vs Planetary Imaging. Those two sub-topics don’t have very much in common – except taking images under the dark night sky. And because of the inherent difference of those two sub-topics there are professional amateur astronomers totally devoted to the one or the other section. We will learn what the specific properties of DSO or Planetary imaging are, what differences there are concerning the hard- and software and so on and so forth.

#1.17: Stacking – Exposure Time & SNR

Hey folks, today’s video is about the term stacking. We will cover the basic principles of stacking – including the basic math and statistics behind it. Why are some images noisy and others are not? Thereby we will talk about random photons, the law of large numbers, distribution patterns…. How long should the total integrated exposure time be? And how long a single light frame? For visual representation I wrote a python-script creating a virtual sensor with virtual photons representing virtual physical objects.

To be continued!