Very strong light pollution near the horizon
Shooting straight up minimizes the glow effect, allowing a better overall picture
20 × 5s stacked
A set of 25 pictures at 5 seconds exposure, ISO 800, stacked (and around 3-5 dropped), with 25 black frames as well. A bit lower noise as a result.
Uetliberg and stars
A portrait shot shows better the contrast between horizon and (almost) overhead
Another portrait shot