This series at f/1.4 and f/2.2 and f/3.2 looks at the Sigma FE 105mm f/1.4 DG HSM Art at far distance for astrophotography. It speaks to practical considerations as well, such as focusing.
Sigma FE 105mm f/1.4 DG HSM Art Aperture Series: Stars Over Mt Whitney, Pre-Dawn Deep Blue Sky
Includes image up to full camera resolution.
I am planning on shooting something like this from another vantage point with the Fujifilm GFX100 and the Fujifilm GF 250mm f/4 R LM OIS WR, assuming I can get similar atmospheric conditions.
Stars Over Mt Whitney, Pre-Dawn Deep Blue Sky
f3.2 @ 30.0 sec EFC shutter LENR off, ISO 100; 2020-03-24 06:02:17[low-res image for bot]
Sony A7R IV + Sigma FE 105mm f/1.4 DG HSM Art
ENV: Alabama Hills, altitude 5200 ft / 1585 m, 30°F / -1°C
RAW: LACA corrected, vignetting corrected, push 1.1 stops