Portrait lens on APS-C

I think it comes down to the kind of photographs you want to take.

Due to the inherent characteristics of APS-C, you really need a longer lens to get the same level of background blur as a full from. Most people love background blur, so when I want that on my 7D, I like the 70-200 2.8.

Of course that changes the perspective of the photograph dramatically.

The 50mm 1.8 is pretty good when shot wide open, or close to it. Once you stop down too much, the aperture blades sometimes do some funky stuff to the bokeh.

I've seen great portraits on APS-C with the 35mm 1.4 as well. Including a bit more of the setting can add valuable context to the image.

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