Thanks for that.
I will have to see if I can try both before I commit to buying one based on this information, you may have saved me from making a mistake.
Hi Don.I tried an experiment where I placed a target 25 feet away and took pictures with the 70-200, with the 1.4X, and with the 2X on a 60D and a 5D2 and then pixel peeped to see how much detail I could see in the final image. On the 5D2 the most detail was with the 2X, then the 1.4X, and then the bare lens. On the 60D the most detail was with the 1.4X, the the 2X, then the bare lens.
What is the reasoning with not bothering with the 2X converter on a crop body, a 1.4X would only give me 448mm equivalent, a 2X would still only give me 640mm equivalent, whereas I am already used to running out of zoom at 800mm equivalent.
If for some reason it would degrade the image below the quality of the Sigma then it would be a waste, if it is only (only ha) for the 2 stops of light lost with a 2X converter, that would make it the same as the Sigma at 150mm and a whole 1/3rd of a stop better at full reach all be it less reach than the Sigma!
What I'm trying to say is that I'd love the extra reach but I'm open to reasoning on why not to?
Here I am debating something that could be months away! Aaah the planing stage!
A crop camera, with the smaller pixel size, is more sensitive to lens resolution than a FF camera. Adding in a teleconverter adds in distortion, and with crop cameras teleconverters do not work well unless you have a very sharp lens.
7DII+Grip, 7D+Grip, 40D+Grip, 5D+Grip, EF 24-105 f4L EF-S 17-85, EF-S 10-22, EF 70-200 f2.8 L IS II, EF 2x III, Σ150-500, Σ17-70 f2.8-4 C, EF 50mm f1.8, 550EX, Triopo TR-985, Godox FC-16, Filters Remotes Macro tubes Tripod heads etc!
5D, 20D, 24-105, BG-E4, BG-E2N, 17-85, Nifty 50 pre owned. 😀