Been shooting on Canon for a good ten years now and finally upgraded to the 90D last year because I wanted that 32.5 megapixel sensor for my bird shots. Its been great but lately Ive been getting really into the tiny stuff in my backyard here in Oregon. I tried using my 70-200mm f/4L but even at the closest focus distance I just cant get the magnification I want and even when I crop in like crazy it just looks mushy. Im losing all that detail I specifically bought this high-res body for in the first place. I am looking to get a dedicated macro lens but I am honestly stuck on which way to go because the 90D sensor is so demanding.

I know the EF 100mm f/2.8L IS USM is basically the gold standard for most people but I have heard some folks say it might be overkill or that the diffraction kicks in way too early on this specific high-res crop sensor. I am also looking at the Tamron 90mm or even that crazy Venus Laowa 2:1 lens but I am worried about losing autofocus for when I am not doing 1:1 stuff. My budget is probably around 700 bucks maybe 800 if its really worth it. I need to figure this out by the end of next month because I am heading to a huge botanical garden event and I want to be ready to get those really tight textures on the petals without having to carry a massive tripod everywhere.

The 90D has that weirdly high pixel density so I am nervous about getting a lens that isnt sharp enough to keep up with it. Like if the glass is soft it is just gonna look terrible at 100 percent zoom and I dont want to waste money on something that wont resolve. Does anyone here have hands-on experience with this specific body and a macro setup? Is the non-L Canon 100mm still a solid choice or should I just bite the bullet and go for the L series or maybe a Sigma? I really want that 1:1 ratio without having to stand three inches away from a bee. Whats the best move for a 90D user who needs sharpness above everything else?