Why am I doing it again?
It’s been two years since my comparison article between the Sony 24-105mm and the Tamron 28-75mm. It is still one of the most popular ones, together with the corresponding video. In that article I concluded that I will pick Sony over the Tamron, because of a few reasons. The Sony has optical stabilization (Optical Steady Shot or OSS). It has an assignable button. Has better corner sharpness. Has better range, and on a high megapixel camera like A7RIII or A7RIV you end up with a 37-152mm lens in APS-C mode.
Two years later, with a A7RIV in hand, and after 1-2 major firmware updates from Tamron, I decided to test and compare the two lenses again. First to see if Tamron improved the video autofocus, and second to see how both lenses handle the 61Mpx resolution. In addition, Tamron increased the price of their lens with $80 and Sony reduced theirs, so they are now even closer price-wise. I’m currently preparing two videos (comparing sharpness and AF speed in stills and video) to supplement this article. I will place a link here once they are live.