Would you add a 2x and/or 1.4x (all Mk3) to a 5d3 + 200L 2.0 combo or rather get a used crop body and get a 1.4x only? This is one area where I am not very experienced and need some help. I just need reach, but I don't need it uber super sharp top quality. I am not going to use this combo in wild life, it will be just for shooting for fun, planes, helicopters, buildings, things far away, nothing too exciting (mostly stuff for my little one). I obviously don't want the pictures to look like iphone pictures and a few hundred dollars here and there is not a concern. As the next best thing for me is 10 grand (400 2.8), I thought the extenders and/or crop body would give me a decent result using my 200 2.0 prime.
I did try both 1.4x and 2.0x extenders with this prime and the 1.4x was just phenomenal, it would focus instantly and produce very sharp images. 2.0x was also quite impressive, focus was very fast (WAY more than enough for what I am trying to do) and image quality was also pretty (shockingly) good.
If I don't get a crop body, I don't see myself ever getting the 1.4x because 280mm isn't really that much more than 200mm (at least not worth the trouble for putting the extender on), I would most likely get the 2x only.