The non-IS 70-200 f/2.8 is actually an optically better lens than the original 70-200 f/2.8 IS (though the IS II is better than either of them). Optically, the f4 and the f2.8 are both excellent… is one of them is better, the difference is not significant. With that said, I have zero interest in buying the 70-200 f4 or for that matter the Sony 70-200 f2.8. The new Tamron really does look interesting and I would love to try it out. Especially in the Grand Canyon or Watson Lake here in the Prescott area. Dustin Abbott gave a positive general overview on this Tamron. We're finally reviewing the Canon RF 70-200 f/2.8L! This is the last RF lens from my new wedding kit to review and it has been highly requested. You will not Just wondering if Fuji will come out with 70-200 mm f2.8 full frame equivalent in the near future? I use the 70-200 f2.8 on my Canon 5d mk 4 about 90% of the time. Btw, before anyone says the Fuji 50-150mm f2.8. That lens would be more equivalent to the full frame 70-200mm f4 Lens but technical guys here will already know that. The Tamron 70-200 VC has noticeably better image quality than the Sigma 70-200 OS at f/2.8. The differences are less noticeable at f/4, but the Tamron remains the image quality leader except at 200mm where the Sigma performs better in the corners. You buy a 70-200 f/2.8 to use at f/2.8. Otherwise, buy a Canon EF 70-200mm f/4 L IS USM Lens. It But what I'd consider doing for this trip: RENT the 70-200 F2.8L IS II and a 2.0X teleconverter and use those instead of the 70-200 F4. the 70-200 F2.8Lis a lot bigger and heavier than the F4, but it's faster, and the IS II version handles a 2.0x tele fine, so you get that extra reach with a 400 F5.6 equivalent, and it's a really sharp combo. Canon EF 70-200mm F/2.8 L IS USM II Lens 5th Group Ass'y Parts YG2-2656 Mark II $188 Canon EF 70-200mm F/2.8L IS II USM Genuine Zooming Ring Part - YB2-2078-001 Canon EOS 40D Canon EF 50mm F1.8 II Canon EF-S 15-85mm f/3.5-5.6 IS USM Canon EF 70-200mm f/2.8L USM Canon EF-S 55-250mm f/4-5.6 IS STM +5 more Reply Reply with quote Reply to thread Complain At 200mm, f/4 can blur the background, but f/2.8 can provide more blur. The primary benefit the Canon EF 70-200mm f/2.8 IS L USM Lens has over the non-IS version is IS (Image Stabilization). (note: the Canon EF 70-200mm f/2.8L IS II USM Lens has replaced the version 1 lens and adds image quality to the advantage list). Aside from the feature Product description. The Canon EF 70-200 F4L IS II USM is a substantial upgrade over the original model. Its image stabilization now reduces shake by up to 5 stops (versus 3) and is quieter, the body is more durable and coatings have been added to reduce ghosting and flare as well as to keep fingerprints off of the front and rear elements. The 5SZ2.