Cropping 2x 16:9 anamorphic?

[BrorSvensson]

Hi! Im thinking about getting a sankor 16c for my setup to use for fun every once in a while, im using a Sony A7 and Nikkor Ai primes. With the 2x anamorphic i will be getting a 3.5:1 aspect ratio and that's little wide for me. I would like to get an aspect ratio of around 2.5:1. How much image degradation will it be to crop the 3.5:1 down to 2.5:1? Is it an valid option?

 

[Gabriel Copoeru]

open a sequence in premiere with 2560x1080 resolution, pop in that footage, stretch width 2x, boom, your'e done

no degradation, just some detail that will be left out from 2.39 to 3.5

[Julian Krause]

With the de-squeezing method from Gabriel you will get some small image degradation because you are stretching your image horizontally by a factor of 2x. So you are effectively up-sampling horizontally. Vertically you still got the full resolution so no change there. All in all the de-squeezing in this case is hurting the horizontal resolution a bit, but from my experience this will only be a minor if not negligible degradation. 

I actually did the same thing because my A7s can only record in 16:9 and I got a Rectimascop 48/2x anamorphic adapter.