Opinions on the RF 28-70/2 vs RF 24-70/2.8 in terms of IQ?

travelinbri_74 wrote:

Setting aside the larger aperture of the 28-70/2 - which is clearly the reason to get this lens - I am curious how the two lenses compare in terms of IQ - and particularly sharpness - at competing focal lengths and apertures?

Brian does reasonably repeatable testing. As you can see by playing around with various focal lengths at F2.8 there is no clear winner. However, even at F2.9 they aren't identical. There seem to be more cases where the RF28-70/2L is sharper in the middle and more cases where the RF24-70/2.8LIS is sharper away From the middle but that also depends on which FL being examined.

https://www.the-digital-picture.com/Reviews/ISO-12233-Sample-Crops.aspx?Lens=1415&Camera=1221&Sample=0&FLI=2&API=0&LensComp=1223&CameraComp=1221&SampleComp=0&FLIComp=2&APIComp=2

Personally, I find them both to be plenty sharp.  The RF28-70/2L comes out a lot less frequently but is excellent when that extra stop is needed to create the right subject separation in a busy environment, while the RF24-70/2.8LIS is the best ever for its class and is useful for everything: landscapes, handheld night shots of the city, portraits, candids, etc.

With IBIS coming and their IQ being so close – cost, weight, size, and filter expense are the only remaining and substantial differentiators.

Like you said, f/2 is THE reason to choose the 28-70, but it is difficult to underestimate the difference that makes in the image character. The 28-70 @ 70mm/f2 renders like a Zeiss prime, which is quite astonishing for a zoom.

Don't know about the 28 70, but the rf 24 70 2.8 does it all for me. Ofcourse sometimes i think, hmm would the character of the 28 70/2 would make that difference,. Maybe. But to be honest, as a photographer, you also make the character with the editing and the composition. For versitality the 24 70 with IS makes the difference.  And sharpness? Although i'm quite influenced by the internet about sharpness this and that, for portraits it shouldnt be too sharp, or at least, i don't think it will make any difference whether your photo will be more a succes would it be this little bit sharper. All i can say is that i trust my 24 70 for the 100 percent. Fyi, just a few pictures during assignments. (already editted)

the 28-70 have mojo, the 24-70 no

PGSanta wrote:

highdesertmesa wrote:

With IBIS coming and their IQ being so close – cost, weight, size, and filter expense are the only remaining and substantial differentiators.

Like you said, f/2 is THE reason to choose the 28-70, but it is difficult to underestimate the difference that makes in the image character. The 28-70 @ 70mm/f2 renders like a Zeiss prime, which is quite astonishing for a zoom.

My 28-70 was a tough return, but I did so because I just didn't think it offered a close enough rendering to a good 1.8 prime (let alone a 1.4, or 1.2). I sent it back on the hunch that id' be happier with the IS zooms when I needed a zoom, and primes when I needed speed. I'm happy I went that route, as the 15-35, and 24-70 that Canon has released are fantastic.

I think the only real way you'll know for sure if the f/2 is something that will impress you, is to use the lens. Some folks love it, with good reason. I feel it's an impressive design, but for just about 99% of scenarios where I'd be shooting close to f/2 I'd rather use a fast prime that would almost certainly give me a superior image.

I get and agree in part with what you are saying. But to me the only real ready to choose the 24-70 over the 28-70 is... the 4mm on the wise and, and weight/size, which can be offset by the f2.  
Once IBIS is out, the IS in the 24-70 becomes less of an advantage (I mean 7 stop combined IS vs 5 stop IBIS can be a bit of a differentiation). After all the cost of both lenses are relatively close. 
Regardless though, the f2 speed can simply mean lower ISO settings in dim conditions where IS doesn't help which translates directly to better IQ (if you can deal with a shallower DOF) and potentially also improved AF.

Do you need/want f2? 
Are you ok with the size/weight of the 28-70?

Are you ok without the 4mm on the wide end?
Are you willing to pay 500 more for the f2 over the f2.8?
With IBIS I think the 28-70 f2 becomes better value (relative than before) compared to the 24-70. The fact that it is like a bunch of f2 primes all rolled into one is actually quite nice. 
To me at least, the size and weight is a major thing. If it were the same size/weight as the 24-70 f2.8 IS I would prefer it. But the fact of the matter is that there is a risk of leaving it at home. Big zooms always draw more attention but from what I have heard the 28-70 is even a step beyond that... 
End of the they, it is up to each person to determine this for themselves. And as usual the best way to know is to go to a shop and have it look. I thought to myself that I would be willing to deal with the size and weight. But I have held it in the shop since then, and the one thing that came to mind was the following... "If I did photography for money... heck ya!! If I doesn't make money from my photography, if I don't shoot A LOT... WOW it is a massive beast!!" Still want it due to GAS... but it is a beast of a lens... and my priority would be to own the 70-200 f2.8 before the 28-70 f2, and before I consider trading in the 24-105 f4 for it or the 24-70f2.8. Pragmatism would have be pick up the latter over the 28-70f2 and throw the savings over to the 35f1.8 or hopefully by then an RF 50f1.8

people who tell take the 28-70 only if you need f2, need to change hobby or job if it's photo relate.

the 28-70 have a totally different image rendering, probably less sharp, but more more organic. even at different f-stop

Peter_Non wrote:

people who tell take the 28-70 only if you need f2, need to change hobby or job if it's photo relate.

the 28-70 have a totally different image rendering, probably less sharp, but more more organic. even at different f-stop

Many of us don’t really mean to discount the rendering when we talk about f2 and f2.8. But the description of organic and such is well... subjective.

There is the specs aspect of the lenses to consider, and the physical aspect of it etc. But for rendering, all OP has to do is look up many examples and determine for themselves if the rendering tips the balance towards getting it.

After all it ain’t just about rendering. Let me put it this way. I have been considering trading the 24-105 f4 for the 24-70f2.8. That is going from 600 grams to 1000 grams. The weight increases besides the additional cost kinda holds me back. With the R5 announced I thought that with IBIS I should consider the 28-70f2 as well. But man... 1430 grams. That isn’t nothing.

Is the rendering and f2 with the added price and weight? Will this lens stay home more than if you have the 24-70? I often leave the 24-105 at home and just take 1-2 primes with me. If I had the 24-70 I would likely have it with me instead of the primes more often. But that 28-70, may just be too much.

So... OP has some more balancing to do. Think we might have opened up more questions than answers. I do have to say that the rendering is great. But I had that sort of rendering with the zeiss lenses I had on the Sony system. When canon comes out with F1.8 primes. If zeiss comes out with some Loxia like lenses... would the 28-70 still be the lens you grab on the way out? I think I would go with 2 primes and the higher MP of the R5 most of the time. 😛

PGSanta wrote:

highdesertmesa wrote:

With IBIS coming and their IQ being so close – cost, weight, size, and filter expense are the only remaining and substantial differentiators.

Like you said, f/2 is THE reason to choose the 28-70, but it is difficult to underestimate the difference that makes in the image character. The 28-70 @ 70mm/f2 renders like a Zeiss prime, which is quite astonishing for a zoom.

My 28-70 was a tough return, but I did so because I just didn't think it offered a close enough rendering to a good 1.8 prime (let alone a 1.4, or 1.2). I sent it back on the hunch that id' be happier with the IS zooms when I needed a zoom, and primes when I needed speed. I'm happy I went that route, as the 15-35, and 24-70 that Canon has released are fantastic.

I think the only real way you'll know for sure if the f/2 is something that will impress you, is to use the lens. Some folks love it, with good reason. I feel it's an impressive design, but for just about 99% of scenarios where I'd be shooting close to f/2 I'd rather use a fast prime that would almost certainly give me a superior image.

I'm trying to think of a Canon f/1.8 lens prized for it's bokeh rendering. Some like the RF 35 f/1.8 come close I guess, but you'd probably only know the difference if you shot the same scene with both. Slightly off topic, but I've found the RF 28-70 and RF 50 when both shot at f/2 near MFD have identical bokeh character.

When choosing between the 24-70 vs 28-70, I also try to encourage people to consider 15-35 / 50 / 70-200 and forget the standard zoom altogether. Once you have the 15-35 and 70-200, you really only are missing 40-65. The RF 50 f/1.2 is a brilliant lens, perhaps the best in the entire RF lineup so far.

PGSanta wrote:

lawny13 wrote:

PGSanta wrote:

highdesertmesa wrote:

With IBIS coming and their IQ being so close – cost, weight, size, and filter expense are the only remaining and substantial differentiators.

Like you said, f/2 is THE reason to choose the 28-70, but it is difficult to underestimate the difference that makes in the image character. The 28-70 @ 70mm/f2 renders like a Zeiss prime, which is quite astonishing for a zoom.

My 28-70 was a tough return, but I did so because I just didn't think it offered a close enough rendering to a good 1.8 prime (let alone a 1.4, or 1.2). I sent it back on the hunch that id' be happier with the IS zooms when I needed a zoom, and primes when I needed speed. I'm happy I went that route, as the 15-35, and 24-70 that Canon has released are fantastic.

I think the only real way you'll know for sure if the f/2 is something that will impress you, is to use the lens. Some folks love it, with good reason. I feel it's an impressive design, but for just about 99% of scenarios where I'd be shooting close to f/2 I'd rather use a fast prime that would almost certainly give me a superior image.

I get and agree in part with what you are saying. But to me the only real ready to choose the 24-70 over the 28-70 is... the 4mm on the wise and, and weight/size, which can be offset by the f2.
Once IBIS is out, the IS in the 24-70 becomes less of an advantage (I mean 7 stop combined IS vs 5 stop IBIS can be a bit of a differentiation). After all the cost of both lenses are relatively close.
Regardless though, the f2 speed can simply mean lower ISO settings in dim conditions where IS doesn't help which translates directly to better IQ (if you can deal with a shallower DOF) and potentially also improved AF.

I mean, you're not wrong. Some days I'd probably even agree with you. It's a tough call. I'm glad we have to struggle with it Maybe one day I'll fill out my RF lineup and feel justified in a purchase of both.

lol. Right back at ya.

If I were making double my salary I wouldn't even be discussing it. I would have R5 with all the nice f1.2 primes. AND I would have something like the EF-M with 3 small primes for one the go. That way I would definitely have the 28-70 instead of the 24-70, since I would have the 70-200 and 15-35. There would be no question that they would stay at him 50% of the time, but for golden hour photography all those RF primes would definitely shine. 
However... in my present reality think the wife and the kids rather I spend the money on trips and on them

I would suggest that if you can’t get insanely sharp photos out of both of these lenses you are better off investing in yourself than one of these lenses.