Outside the sanctum of astrophotographers, it is a little known fact that astrophotography is the most difficult discipline in the realm of photography, where the factors of environment, the element of weather, the cooperation of equipment and operator must all align (I hate to use this term as it draws parallels with charlatans) to assist each other in reaching the penultimate destination; that is, an aesthetically pleasing photograph.
It's unfortunate that we don't see too many of these types of vistas, and, even if this was just simple experimentation at high ISOs, I commend you for having the foresight and vision to create this landscape.
What we see presented here is a stunning view of our home -- the Milky Way -- as it sets over the distant mountains, and, if I'm not mistaken, the residual cone of zodiacal light to the left. If we draw an imaginary line through the centre of both, we create a triangle, with its top-most point just shy of centre-left.
To create another triangle: the bright point light source to the left is the planet Jupiter, sailing through Capricornus. The bright star towards the centre-top of the image is Altair, which is also known as Alpha Aquilae (the brightest star in Aquila). The bright star (just above the mountains) which can been seen in the reflection of the lake is Kaus Australis (Epsilon Sagittarii), the brightest star in Sagitarius.
The eye is assisted to being drawn towards the Milky Way, due to the parallel vignetting which is present as a result of the wide angle lens. Whilst vignetting is sometimes desirable for terrestrial photography (for example, framing a bride and groom at a wedding), it is a massive problem for us astrophotographers (especially on full frame sensors), and, we've developed techniques to combat it. These techniques are beyond the scope of this critique, and, in all honesty, the darkening here aids the visual impact of the composition.
The chrominance noise in the sky is a little distracting, and, could be better handled, but, having said that, I realise this is an experimental exposure and therefore can be let it slide.
The 30 second exposure chosen for this shot is just right, too. Anything longer than approximately 40 seconds at 17mm, and the stars would have trailed significantly enough to be noticeable.
Sublime images like this have a profound impact on the viewer. Personally, they take me to a place void of humans; this is what the first people would have seen (sans light pollution and sky glow). This Romantic notion is juxtaposed, somewhat, by the presence of satellite trails (most likely Iridium and COSMOS communications satellites) gliding on their paths through the heavens.
If you'd like a detailed map of what it is that we're looking at in the sky, please don't hesitate to ask.
It's so beautiful. It kills me that here in the cities, we see barely 1/10 of the stars that appear in your photo. Thankyou for sharing this with us. I swear I will travel somewhere to see a nightsky like this for myself one day.