Quote:
Originally Posted by dannat
Terry used for nightscape, wide fields, either as single exp or stacked or stitched to video
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For that use then as stated above you can get away with a bit shorter exposures with the faster lens. For stars it would make little difference as they would probably be extremely undersampled anyway. Assuming a very short focal length, a star would be smaller than an individual pixel. The faster lens has to be a bit bigger in diameter so in theory has slightly better resolution but optical aberation may null that effect anyway.
If you can afford the faster lens go for it as you can always stop it down and probably achieve a better image than the slower lens wide open.