Thank you very much!For the RF 14-35mm, the uncorrected FoV is slightly less than 13mm. The distortion correction reduces the FoV, but because the image is 'stretched out' (after being 'squished' by the distortion), not through cropping. Having said that, there is some cropping at the sides to keep the 3:2 aspect ratio, because there's more stretching on the longer axis of the image, resulting in an EOS R output that's 305 pixels (4.5%) wider than the native 6720 pixels, and those extra pixels cropped away by Canon/Adobe (but optionally not by DxO) to keep the 3:2 ratio and native output dimensions.
All of those details (and more) are included in my tests of the 14-35 at the wide end:
RF 14-35mm f/4L IS – Distortion Correction Testing
Mirrorless cameras lack an optical viewfinder, so looking through the lens is always an electronic process. This fact enables lens manufacturers to include consideration of digital optical corrections in their lens designs and make trade-offs accordingly – more optical aberrations can be...www.canonrumors.com
Simple explanation for the cropping in the article you link. "Supreme Court of Ohio – Distortion Corrected and perspective corrected," then, "The uncorrected image is also a fair bit wider than 14mm, with the field of view reduced a little when correcting the distortion, however, natively it’s not quite as dramatic as shown in the second image, as this also was perspective corrected for keystoning, further reducing the angle of view."
Unlike the site you link, in my tests I ensured that the camera was level and orthogonal to the building to avoid vertical and horizontal distortions. Perspective correction can result in substantial cropping, depending on the amount applied. Here's a rather extreme example of that, taken with the RF 14-35/4 @ 14mm as I walked past the Parthenon in Rome.
Perspective corrected shot:
View attachment 212206
Original shot:
View attachment 212203
Perspective correction step (force-rectangle in DxO), showing how much cropping is needed after the keystoning is corrected:
View attachment 212205
One more point regarding focal lengths. Even though the 14-35/4 gives an uncorrected FoV equivalent to ~13mm, the actual focal length is still 14mm (slightly longer, since Canon always rounds in their favor). Consider that the diagonal AoV of the RF 15-35/2.8 at the 15mm is 110°, while the diagonal AoV of the EF 15/2.8 fisheye is 180°. Both are 15mm, but the first is neatly rectilinear (distortion mostly corrected optically), while the fisheye isn’t corrected (circular projection, massive ‘black corners’). Think of the RF lenses requiring distortion correction as one step down the path from rectilinear to fisheye.
I still haul my 600/4 II around and use it handheld. While not tempted sufficiently to pre-order the 10-20/4, I suspect I'll end up buying it at some point. Like you, I find the easy ability to put filters behind my 11-24 (and my TS-E 17) a big benefit of adapting them to mirrorless. But next summer I'll be hiking in the Alps, and for that the lower weight of the 10-20 compared to the 11-24 will be a benefit.
Thanks, Neuro. I went ahead and ordered the 10-stop gel, the one I'd use most for water and clouds. I'd really like the long exposure option when going to the seashore. Even if my lens doesn't make it in the first shipment, having the gel on hand will mean no delay heading to the beach whenever the lens arrives!Kodak makes a wide range of gels, mostly for color correction, not really needed for a digital camera. NDs are the ones you’ll probably want to use, but they also have them for IR.
KODAK WRATTEN 2 Filters
A leading global manufacturer focused on commercial print and advanced materials & chemicals. We believe in the power of technology and science to enhance…www.kodak.com
Well, the difference between 14mm and 10mm is kinda huge. I know we look at that and think, "It's just 4mm." but, at the wide end, it's huge.If I hadn't bought the RF 14-35mm F4 a year or two ago, I would've preordered asap today. It looks like a really nice lens and the fact it is just 570 gr (still can't believe it) and it cheaper than its EF equivalent is really, really, really tempting, but spending money for just 4mm wider shots is just not happening. Furthermore, my decision nausea would hit new levels (RF 14-35mm or 10-20mm??????) especially for city travels
Enjoy the lens!
I went to the Canon USA website to look at the user manual. When I clicked on the Support Page link for the manual, this came up! https://www.usa.canon.com/support/p/rf10-20mm-f4-l-is-stm
Thanks, good to know the size is different, in the event I decide to buy the RF 10-20. I still have some pristine pieces of 10 ND gel.I went to the Canon USA website to look at the user manual. When I clicked on the Support Page link for the manual, this came up! https://www.usa.canon.com/support/p/rf10-20mm-f4-l-is-stm
Note that the link here (as of 10/13/23) which says, "RF 28mm F2.8 STM" is just mislabled. It is the link to a pdf with the 10-20mm manual.
I'm not sure with the templates how to determine the print size, as they are huge by default. At least Canon has put the measurements on the top, so it won't take to many trial prints to get there. I hope.
Or I could just ask my daughter to use a ruler and pencil for me.
Again, thank you for putting me on the right track with this.
That’s good to hear, Canon used to be waaaaaay in front of new hardware with firmware support, but for RF they tended to behind.
Why does it matter if it's STM or USM or XYZ? I'm pretty sure Canon won't allow a modern L lens to have slow or inaccurate AF. They simply choose the best AF motor for a specific lens. Maybe STM was chosen because of the small size, while being fast enough.
Up until now, my personal experience is that USM is the fastest and most silent AF motor, esp. the new linear nano USM Canon is using lately.
I didn't find any logical reason for that choice in a quick search.
