Alright; I have finally run into shooting situations where 24mm is simply not wide enough to frame things I want on the 5DIV. But, I'm a little stuck over the most useful upgrade to make; I have a couple of targets in mind but would like to get some further thoughts on options or recommendations for things I might not be considering already.
1. Will primarily be used in landscape shooting scenarios
2. *May* be used for family/friends portraiture, but not primarily
3. Would be nice to be able to shoot lower light without a tripod; giving a tip to the f/2.8 or to a good, fast prime
4. Needs to be able to accept filters, particularly a CPL; also, I am a complete dufus regarding blending/layering photos
5. AF strongly preferred
1. Canon 16-35 f/4 L: Top, standalone performer for across the scene sharpness from all I can find.
2. Canon 16-35 f/2.8 L III: Not quite as strong overall image quality, but close enough to justify with it's larger max aperture.
3. Wide, fast prime to be named/suggested
C 11-24, while I would probably enjoy that lens overall, the bulbous front element/fixed hood will frustrate me with not being able to use a CPL
C 14mm 2.8/Rokinon 14mm AF, same as above.
Thanks in advance!