17-55 on crop versus 24-105 on FF

How is the quality of the 24-105 on a FF versus a 17-55 on a crop?
I know they are different focal lengths even if adjusting for the crop and I'm not concerned about the 1 stop difference in speed between the two.
If I decide to get the 5d mark III, I'd like to know how the 24-105 compares to my 7d with the 17-55. Getting the 24-70 would be too much money.

I find the 24-105 to be a little handier just on the merits of the broader focal length range, especially on the wide end.

Both are sharp, though the FF camera can often deliver a bit more sharpness overall if it is a 5D2 or similar.

The downside of the 24-105? The distortion and vignetting on the wide end is pretty hefty. Then again, these both get a lot better by 28mm, which is as wide a FOV as the 17-55 is capable of on 1.6X. So it's hard to ding the lens for being a bit weak in a range that the other lens cannot even provide.

Having shot a 7d with a 17-55 and the 5d3 with the 24-105, I feel compelled to say that the 17-55 was sharper at both f2.8 and f4. But the 24-105 is more compact and lighter, yet feels higher quality. For example my 17-55 had some pretty severe zoom creep, while the 24-105 doesn't creep at all, and actually has a nice, tight zoom ring and focus ring.

Another point is that the 24-105 has better color rendering than the 17-55.

Overall, since I don't think sharpness is the be-all, end-all, I like both lenses equally. The 24-105 is the better, more flexible walkaround, but the 17-55 is a helluva lens as well.

bobfather wrote in post #15345663
Having shot a 7d with a 17-55 and the 5d3 with the 24-105, I feel compelled to say that the 17-55 was sharper at both f2.8 and f4. But the 24-105 is more compact and lighter, yet feels higher quality. For example my 17-55 had some pretty severe zoom creep, while the 24-105 doesn't creep at all, and actually has a nice, tight zoom ring and focus ring.

Another point is that the 24-105 has better color rendering than the 17-55.

Overall, since I don't think sharpness is the be-all, end-all, I like both lenses equally. The 24-105 is the better, more flexible walkaround, but the 17-55 is a helluva lens as well.

The 24-105L is actually slightly heavier than the 17-55 f/2.8 -- 1.42 lbs. vs. 1.40 lbs.

I also used to own the EFS 17-55 that I used on a Rebel XT, 40D and 7D -- and now own a 5D3 with 24-105L. The 17-55 does not suffer from the flaws of the 24-105L -- namely distortion at the wide end, vignetting and CA. However, all these things can be fixed easily in Lightroom.

That being said, I still find the 5D3 + 24-105L a more useful walk around combination than the 7D + 17-55 f/2.8. I get more focal range both at the wide and telephoto ends, and the loss of one stop is negated to some extent by the 5D3's superior high ISO performance. Image quality, with a little work in LR, is still excellent.

Had them both - 17-55 on a 40d and 24-105 on a 5dii. They are very similar lenses in terms of build, IQ, AF and general performance. What differences there are between them are not significant IMHO. There's a bit more 'reach' on the 24-105, even after the 'crop factor' adjustment.

The 5dii on the other hand is streets ahead of the 7d in the IQ department, and I would think the 5diii will be just as good or better than the 5dii, but with an AF system to match the 7D.

Trying to make a decision between three lenses:

Tamron 24-70 f2.8
Canon 24-70 f4 IS
Canon 24-105 f4 IS

My benchmark is the Canon 17-55 f2.8 IS on a XSi. I'd be using these lenses on a 6D.

For me, the difference between f4 and f2.8 is less about that stop of light and more about sharpness wide open (which I can compare via, e.g., thedigitalpicture's tool) so I'm mostly curious on these characteristics:

1) autofocus speed
2) autofocus accuracy
3) color reproduction
4) sharpness (in going from 17-55 to 24-xxx on crop --> FF. thedigitalpicture's tool isn't quite as helpful in this regard as it compares either a 60D or 50D to a 1Ds Mark III -- in almost every case the resolution of the sensor largely skews the result in favor of the EF lenses)

I'm very impressed with my 17-55, but its zooming system has crapped out twice now. Of course I'd like whichever lens I get to surpass the 17-55 in each of these categories, but I'm curious about what I'd be sacrificing when moving to full-frame.

On second thought... I've forgotten the 1Ds III is 22 MP (just like the 5DII). If the IQ increase from 60D+ 17-55 to 1Ds III+24-105 is indicative of XSi+17-55 to 1DsIII+24-105, then that should just about seal in that lens as being an IQ equivalent to the 17-55.

Then the question becomes AF. Between the Tamron, 24-105, and 17-55, how does AF speed and accuracy compare?

I absolutely love my 24-105 for what it is. Easily the best bang for buck zoom on FF with good handling, build quality and a decent price tag (especially used).
Since it's essentially a kit lens, there's many upgrade paths (24-70 2.8 and primes). That ensures there's always a steady offer on the used market.

It's still my go-to lens for strobist portraits, together with the 85mm 1.8.

I chose 17-55 on crop. Had the other combo, sold it.

Comparing apples and oranges! Remember that IQ is the product of Lens * Format.

In the case of 17-55mm on 15MPixel APS-C, it can resolve 2536 line-pairs of detail in the APS-C frame height.

The 24-104mm on 15Mpixel FF, it can resolve 3409 line-pairs of detail in the FF frame height.

Both MTF values published by photozone.de and you cannot tell how much performance is lens, and how much performance is format.


But if we look at how the 24-105mm does on 15Mpixel APS-C, we see that the 24-105mm trails the 17-55mm by just a tiny bit, at peak MTF of 2448 line-pairs of detail. A not statistically signficant difference...it might have been a test of a good 17-55 vs. a mediocre 24-105, but if we tested two other samples, the result might be flipped the other way around.

Wilt wrote in post #15970651
Comparing apples and oranges! Remember that IQ is the product of Lens * Format.

In the case of 17-55mm on 15MPixel APS-C, it can resolve 2536 line-pairs of detail in the APS-C frame height.

The 24-104mm on 15Mpixel FF, it can resolve 3409 line-pairs of detail in the FF frame height.

Both MTF values published by photozone.de and you cannot tell how much performance is lens, and how much performance is format.

You summarized this extremely well -- that's exactly what I was thinking. Overall, 24-105 + FF seems to be offer more resolution than APS-C + 17-55, at least with the specific lens and body combo used from photozone.de

So my question stands now as AF speed and accuracy. How do the two compare there?

tigerotor77w wrote in post #15970674
So my question stands now as AF speed and accuracy. How do the two compare there?

AF speed and accuracy are somehow linked to the body too imo. For example, a 7D + 17-55 will probably gives higher hit rate than say a 5D2 + 24-105.

But if you are comparing just the lenses, I think they are close. However let's not forget that 24-105 has better build, not a dust magnet and it's weather sealed (with a filter).

Simply put, the ff combo is (almost) better than crop in every single way. Exactly why I made the switch long time ago after realizing the best crop camera + best crop zoom still lags behind ff + mediocre kit zoom.

solara wrote in post #15345617
How is the quality of the 24-105 on a FF versus a 17-55 on a crop?
I know they are different focal lengths even if adjusting for the crop and I'm not concerned about the 1 stop difference in speed between the two.
If I decide to get the 5d mark III, I'd like to know how the 24-105 compares to my 7d with the 17-55. Getting the 24-70 would be too much money.

If you go FF, another alternative, if it hasn't been mentioned is the Tamron 24-70 f/2.8. Its often been noted that its close to the IQ of the Canon version, has VC (Tamron's IS) which the Canon version doesn't have, and sells for over $900 less. The build is considered very good and its a whole stop faster than the 24-105. Not pushing it, just laying it on the table.