[Klaus]

Meh ...

http://www.opticallimits.com/canon_eos_ff/1052-sigma2470f28art

[Paul1980]

Maybe it will be the Life-saver for the Canon EOS RF system, that the EF system somehow fails to have a really awesome standard zoom (first & 3rd party).

I had the Tamron G1, which was extremely unreliable and spent more hours in service than in action, I skipped the Canon mk1 because you guys warned about a bent focus plane, the mk2 was too expensive and didnt even offer IS (plus, I heard from owners who were not happy with it).. 

now the G2 and the Sigma Art also appear to be very flawed for the price point.

If Canon manages to issue a proper RF 24-70 2.8 L IS (which could be possible, at least the 24-105 looks promising already), this could be a positive impulse for the RF system, which suffers from the mediocre body now.

[davidmanze]

It's a difficult decision choosing the definitive 24-70mm F2.8 lens........the G2 wins comfortably at the edges......but!!!

[JJ_SO]

From the range 24-70 I also think it's overrated. The 24-70/4 Z was the first 24-70 I ever bought. In general I think, i it comes to "standard zooms", "more range" is preferrable to "more speed" - as no standard zoom can compete with any modern prime f/1.4. I'm rather satisified with the Sigma 24-105/4 Art especially since I know it's really good at f/5.6. So, a typical sunshine lens. 1 Stop faster would not matter much.

It's a different story (at least for me) if such a lens offers a closer minimal focus distance.

However, I doubt the Sigma compared to the Nikkor 24-70/2.8 II (1270.- to 2700.-) is that much worse. I also miss in OL tests the susceptibility to backlighting. And to me the benefit of very fine AF adjustments of the Sigma as well as the Tamron also have to be considered. But thta's just me, people without dock/tap-in console will not care about that feature.

[Klaus]

Just in case there are naysayers out there ... these are Sigma's own MTF for this lens ...
https://www.sigma-global.com/common/lenses/cas/product/art/a_24_70_28/data/images/mtf.gif

[Rover]

Maybe it will be the Life-saver for the Canon EOS RF system, that the EF system somehow fails to have a really awesome standard zoom (first & 3rd party).

I had the Tamron G1, which was extremely unreliable and spent more hours in service than in action, I skipped the Canon mk1 because you guys warned about a bent focus plane, the mk2 was too expensive and didnt even offer IS (plus, I heard from owners who were not happy with it).. 

now the G2 and the Sigma Art also appear to be very flawed for the price point.

If Canon manages to issue a proper RF 24-70 2.8 L IS (which could be possible, at least the 24-105 looks promising already), this could be a positive impulse for the RF system, which suffers from the mediocre body now.

Who's the "second" party then.
Well, I had a gut feeling that something about this lens was going to be wrong. I'd choose the Tamron G2 if I had been shooping for a 24-70/2.8 lens. This... let's just pretend that it's a bargain bin C lens and forget about it. Somehow I have doubts about the Tokina as well - not only it seems to have the ancient buzzer motor and the miserable "focus clutch", but their other lenses weren't really that inspiring even on 21/24 MP (see the 17-35/4 review Markus did a while ago).

[JJ_SO]

If it's of any interest, there's a fw-update for the lens: https://www.sigma-global.com/en/news/2018/10/02/1881/

But I do't think it will improve much of the optical characteristics.

[Kate619]

I own the sigma 24-70mm f2.8 and I don't see the slow af you talk about on a canon 1dx it's not as fast as canon 24-70mm f2.8 but I shoot events and concerts with it no problem i prefer the look on sigma over the look of canon 

[Brightcolours]

I don't see slow AF being talked about...

[josh08]

Meh ...

http://www.opticallimits.com/canon_eos_ff/1052-sigma2470f28art

Good to see that canon improves  RF 24-70 2.8 L IS. I will surely try to change my lenses after seeing this because currently, The lenses which I am using makes it difficult for me to adjust focus while shooting a video.