I bought this lens late compared to everyone else, I should have pre-ordered it when it was announced because this lens is pretty amazing especially for the price. My advice if you don’t own it yet, just buy it.
Tamron should have put a G master on it, because this acts like a Sony lens, you can update the firmware in a Sony battery, it has fast AF, it has eye AF, and I had to test it but all the lens correction happens right inside the body, not only for stills via Lightroom but for video files too, the barrel distortion correction works, the shading correction works and I couldn’t verify the CA correction works because I couldn’t find any.
The two things I dislike about the lens are the lens hood, it was taking me way too long to figure out how to put it on, most lens hoods you keep turning it while you are thinking about something else, but this one I had to put two labels on it. Also it is taking me sometime over the past month trying to figure out which barrel is for zoom and which for focus. The bokeh balls have concentric rings.
My trio of zooms have changed recently, when this happens I like to see which lens to use when I have overlap, for instance when shooting around 70mm do I use my Sony 70-200 or my new Tamron 28-75mm?
When picking between the Tamron 28-75mm and the Sony 16-35mm when I am between 28-35mm, the Tamron won every single time, the biggest differences came when shooting wide open. The Sony 16-35mm was so bad at f4 I was like wow note to self do not use this wide open between 28-35mm.
When picking between the Sony 70-200 and the Tamron at 70mm – 75mm, the differences were not as big. The Sony won at the higher f stops like f16 and f22 but Tamron own wide open.
16-35mm vs 28-75mm at 28mm f22: Tamron win in center and edge
16-35mm vs 28-75mm at 28mm f16: Tamron win in center and edge
16-35mm vs 28-75mm at 28mm f8: Tamron tie in center and Tamron big win at edge. Video: Tamron wins at edge
16-35mm vs 28-75mm at 28mm f4: Tamron big win center and Tamron big win at edge. Video: Tamron wins at edge
16-35mm vs 28-75mm at 35mm f22: tie
16-35mm vs 28-75mm at 35mm f16: tie in center, Tamron win at edge
16-35mm vs 28-75mm at 35mm f8: Tamron win in center and edge
16-35mm vs 28-75mm at 35mm f4: Tamron big win in center and edge. Tamron f2.8 is better than Sony at f4
Colors looked similar for Tamron and wide Sony
70-200mm vs 28-75mm at 72mm f22: slight win to Sony
70-200mm vs 28-75mm at 72mm f16: slight win to Sony
70-200mm vs 28-75mm at 72mm f8: tie in center, Tamron wins at edges. Video is a tie.
70-200mm vs 28-75mm at 72mm f4: tie in center, Tamron wins at edges
70-200mm vs 28-75mm at 72mm f2.8: Tamron wins at center and edges. Video: tie, but Sony wins for vignetting.