Quote Originally Posted by Cage View Post
What would I do if I was in your position?

At this point I'd keep the D5500. It has the highly regarded Sony sensor, and with the right lens will produce images that will delight and astound you. What it won't do is auto focus with non AF-S lens.

I'd go for the G1 Tamron 70-200 f2.8 VC (I had one and it was excellent) and also replace your 17-50 f2.8. On the D5500 that will give you the FF equivalent of 25-75mm and 105-300mm, if you want longer you could add a 1.4 T/C.

If you want to try UWA shots, the very good Sigma 10-20mm would be a good starting point.

I'd also consider buying the Tamron from a reputable Grey Market seller as they don't seem to have any inherent problems, the lens that is.

Just my two bobs worth.
A good two bobs worth there too!

Alternativebecause the OP has come across as a bokeh junkie .. instead of replacing the Tammy 17-50/2.8(good lens I still have mine ) .. check out the price difference between it, and the much better Sigma 18-35/1.8.
While the focal length is shorter at 35mm vs 50mm, it's still a usable focal length range .. but the f/1.8 aperture it has at max is a greater, more noteworthy enhancement ... something I think will be more tangible as an upgrade.

Personally I wouldn't go with the alternative of Sigma's 50-100/1.8 over the much longer 70-200/2.8's even tho the same aperture advantage applies here as above.
I think when you want telephoto, then longer focal length may be more appropriate.
But if I were a wedding singer .. er, shooter! and had to weight up the pros and cons between a 70-200/2.8 or 50-100/1.8 on APS-C .. the 50-100/1.8 would win every time.

Once again, usage types will help determine which way is the best way to go.