Canon announces the Canon RF 10-20mm f/4L IS STM

I own the 11-24mm. It’s a good lens but it is big and heavy. I’m amazed they made it smaller and lighter and cheaper. My EF lens has probably gone down in value overnight. I have the RF adapter with drop in filters. It’s great for this lens and gives it an advantage over an RF version. I don’t like the outsize filter kits - huge and expensive. Yes tempting but I think I will be able to avoid it. The RF 14-35mm would be a much more useful lens for me. Filters will fit and 14mm is wide enough for most things.
I'm in a similar position, except I already have the RF 14-35/4. It's an excellent lens, and by comparison to the 11-24 the 14-35 actually delivers ~13.5mm FoV after distortion correction and is as sharp in the corners. Very happy with the 14-35/4 as a replacement for the EF 16-35/4.
 
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If this comes out before Black Friday I'd hope for a Deal. Might be sold out for quite some time though. And I'm not sure if Canon would possibly include such a recent lens in their Winter Cashback. German price seems high (still less than UK) but with a discound + selling my Tamron SP 15-30mm G2 I'd consider this.
 
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What is "Peripheral Coordinated IS" and why is it only compatible with the R5?
It is a new stabilization algoritme that should help against the wobbling effect, seen in the corners in video.
 
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In Canon's video, hosted by Rudy Winston, he states the lens features "both optical and digital corrections for linear and other distortions" as if this is a good thing. Well, it's a good thing for the size of the lens and the MSRP... They couldn't have gotten to those things without it.

Anyways, does anyone know if these theoretical MTF charts take into account mandatory distortion correction that will be forced by the camera and editing software? I assume they do not, but couldn't find any concrete answers.
 
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If this comes out before Black Friday I'd hope for a Deal. Might be sold out for quite some time though. And I'm not sure if Canon would possibly include such a recent lens in their Winter Cashback. German price seems high (still less than UK) but with a discound + selling my Tamron SP 15-30mm G2 I'd consider this.
Surprisingly it already has a cashback offer (of £200) in the UK, I never knew that happened with preorders o_O
 
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If this comes out before Black Friday I'd hope for a Deal. Might be sold out for quite some time though. And I'm not sure if Canon would possibly include such a recent lens in their Winter Cashback. German price seems high (still less than UK) but with a discound + selling my Tamron SP 15-30mm G2 I'd consider this.
Adorama says shipping starts Nov 2
 
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Anyways, does anyone know if these theoretical MTF charts take into account mandatory distortion correction that will be forced by the camera and editing software? I assume they do not, but couldn't find any concrete answers.
I assume that Canon’s MTFs do include distortion correction.

Based on the patent for the 10-20/4 that published back in January, the image height at the 10mm focal length (which is actually 10.3mm) is 19.4mm. That means at the wide end, the image circle does not cover the FF corners. Black corners means an MTF of zero, but their plots don’t show that so they must be for distortion-corrected output.

Same goes for other lenses requiring correction to fill the corners (e.g., 16/2.8, 24-240, 14-35/4L).
 
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I assume that Canon’s MTFs do include distortion correction.

Based on the patent for the 10-20/4 that published back in January, the image height at the 10mm focal length (which is actually 10.3mm) is 19.4mm. That means at the wide end, the image circle does not cover the FF corners. Black corners means an MTF of zero, but their plots don’t show that so they must be for distortion-corrected output.

Se goes for other lenses requiring correction to fill the corners (e.g., 16/2.8, 24-240, 14-35/4L).
That's an interesting insight regarding the patent! Well spotted!
 
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In Canon's video, hosted by Rudy Winston, he states the lens features "both optical and digital corrections for linear and other distortions" as if this is a good thing. Well, it's a good thing for the size of the lens and the MSRP... They couldn't have gotten to those things without it.

Anyways, does anyone know if these theoretical MTF charts take into account mandatory distortion correction that will be forced by the camera and editing software? I assume they do not, but couldn't find any concrete answers.
maybe not with IBIS.
There is more to it then just lens design.
 
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It seems like very much an either or situation with a spending decision between the 10-20 and the 14-35. If, however, one were shooting interiors and needed flexibility, it would be such a pain to have to bring both so you didn't have a gap between 20 and 24 if you only had a 24-70 as a second, not quite so wide lens and your ultra wide was the new 10-20. Personally I've been getting great mileage out of a 16 2.8 that I picked up for $200 a few weeks ago after a tip on this site, so this is all a hypothetical problem for some one else's credit card!
 
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Essentially, the lens is as good or better than the EF 11-24mm.

...On the long end, the bokeh should be improved over the EF 11-24mm, the contrast the same, and the resolution does not appear to show a noticeable difference.
With respect, that really doesn’t seem to be true. I agree that at the wide end the two lenses are practically equivalent (at least based on MTFs), which is great for a lens that’s smaller, lighter, slightly wider, and 3/4 the cost.

However, at the long end even though the contrast is similar as you state, the EF 11-24mm definitely delivers better resolution than the RF 10-20. Here are the MTFs of the lenses at 20/24 mm superimposed. Strike that, reverse it. There’s an obvious difference between the resolution lines.

20vs24mm.jpg
 
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I use PhotoStatistica (Mac), and I find that being able to check my shooting history helps me make informed buying decisions. For example, when the EF 16-35/4L IS came out, it was a choice between the f/2.8 aperture on the lens I had and IS on the new one. I looked ay my usage data for the 16-35/2.8L II, and only 1% of my shots were wider than f/4...made it an easy decision to swap them out.


Yes, that makes combinations of those lenses great for travel!
Great tip! I downloaded the app and will test it this evening (it's 7.00 am now in Germany).
 
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With respect, that really doesn’t seem to be true. I agree that at the wide end the two lenses are practically equivalent (at least based on MTFs), which is great for a lens that’s smaller, lighter, slightly wider, and 3/4 the cost.

However, at the long end even though the contrast is similar as you state, the EF 11-24mm definitely delivers better resolution than the RF 10-20. Here are the MTFs of the lenses at 20/24 mm superimposed. There’s an obvious difference between the resolution lines.
from my practical experience, you really don't see that difference between .6 and .7 in the corners and it also has better astigmatism control as well, so should look much smoother. I did say show a noticable difference but i'll make that a bit more clearer. also in your superimposed chart, there's two 30lines/mm the 11-24 is better than the 10-20 on the sagittal not on meridional. think you'd see that much difference? also the 10-20 has higher center resolution at 20mm versus the 11-24mm as well, as it doesn't fall to under .7 until 15mm (think asp-c crop), while the 11-24 drops to .7 at 8mm. so overall i'd call them a draw. overall the 10-20 has more consistent center performance than the 11-24mm.
 
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Based on the patent for the 10-20/4 that published back in January, the image height at the 10mm focal length (which is actually 10.3mm) is 19.4mm. That means at the wide end, the image circle does not cover the FF corners. Black corners means an MTF of zero, but their plots don’t show that so they must be for distortion-corrected output.

Same goes for other lenses requiring correction to fill the corners (e.g., 16/2.8, 24-240, 14-35/4L).
I recall that the wide end of the 14-35 is actually at around 12-13mm, so that a 14mm image is achieved by both cropping and stretching the corners. If the image circle for the 10-20/4 at the 10mm end does not cover the FF corners, there's not much in-camera corrections can do about the dark corners short of cloning. I wonder if the wide-open end of the 10-20/4 is actually wider than 10mm if it needs fairly heavy corrections.
 
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I assume that Canon’s MTFs do include distortion correction.

Based on the patent for the 10-20/4 that published back in January, the image height at the 10mm focal length (which is actually 10.3mm) is 19.4mm. That means at the wide end, the image circle does not cover the FF corners. Black corners means an MTF of zero, but their plots don’t show that so they must be for distortion-corrected output.

Same goes for other lenses requiring correction to fill the corners (e.g., 16/2.8, 24-240, 14-35/4L).
Canon openly admits that their MFT charts are computer simulations. So a computer simulation that seems to includes questionable corrective algorithms after all....
 
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