Bit of a stupid question here perhaps 
If using a 2x extender on for example an f4-5.6 lens
i know i multiply the focal length by 2
but do i double the aperature effectively f8-f11 or do i add 2 stops? f5.6-8 :bonk:
i think its the first but just wanted confirmation
Cheers

If using a 2x extender on for example an f4-5.6 lens
i know i multiply the focal length by 2
but do i double the aperature effectively f8-f11 or do i add 2 stops? f5.6-8 :bonk:
i think its the first but just wanted confirmation
Cheers