Original topic:

S23 Ultra Astro Mode suggestions

(Topic created on: 08-20-2023 05:10 AM)
Active Level 4
Galaxy S
The astrophotography mode is pretty neat and takes great star-field photos given the camera/lens size.
The multi-exposure/averaged approach works nicely but I think the default exposure times could be tweeked a bit to avoid the residual star trailing (or perhaps have an advanced setting to manually force an exposure time). The very rough exposure-time rule of thumb to minimize star trailing is :
 t_exposure ~ 500/f_eq

The 3 photos in the link below of the Lyra constellation with the 3 cameras (no extra zoom) show these astromode exposure times:
 W f_eq=23mm 20sec
 X3 f_eq=69mm 15sec
 X10 f_eq=230mm 6sec

The W exposure is about right. 
The X3 exposure is a bit too long (10 sec would be better)
The X10 which shows significant star trailing should be much less (~ 2 sec).
In the X10 photo below, the double star ε Lyra at top centre is cleanly resolved, a good test of sharp focus. Lyra is a good test for star trailng as it is about 40 deg N declination so medium star trailing.
The photos below, taken on a typical rural night .. skies not super dark, show stars down to ~ 8.5 magnitude (all stars in Tirion's Sky Atlas 2000.0 are seen in photo).

Click on each of the 3 component photos to see full screen.