my best lens for attempt at astro...

as a followup for a previous thread,
which of my listed lenses below would be the best lens to experiment with in astro: 85 1.2, 8-15 f4, or 16-35 f4?

i understand that I will be limited by the feild of view on each choice...
but the larger aperture of the 85 seems attractive in regards to the light capture and possibly reducing the ISO, no?

granted, nothing is preventing me from trying all of them
but I would like to get a feel from those with more experience than I (almost everyone)
which would be the "best" or the most forgiving? or the easiest lens to do first attempts on.....

thanks a bunch

The problem with long lenses is that you're restricted to short exposure times, otherwise you end up with trailing. Your 16mm lens on the 5D will let you do exposures of around 20s, whereas the 85mm will limit you to less than 5s.

thanks. i will then focus my attempts on the wider lenses.
it will be fun to experiment. it isnt my focus in general, but celestial photography has piqued my curiosity
so i want to invest some effort and time
but i am leaving soon....

anyway, thanks for some practical beginning advice.