The-Digital-Picture has completed their review of the RF 24-105mm f/4L IS USM for the Canon EOS R system.
Compared to the EF 24-105mm f/4L IS II, Bryan found the RF version to be slightly sharper with less linear distortion, but it did show a bit more vignetting.
The RF 24-105mm f/4L IS appears is a great option for an all-purpose lens for your EOS R, especially if you want the native mount.
With this lens, you get an ultra-useful focal length range in a lens sized for comfortable long-term use without creativity-killing fatigue. This lens smoothly focuses very fast with consistently excellent accuracy and the image quality is great with 5-stop image stabilization helping to maintain that desired quality. This lens is well-built, including weather sealing, and is ready for professional-duty use, but it does not cost a fortune. Read the full review
You can buy the RF 24-105mm f/4L IS on its own, or part of a kit with the Canon EOS R body:
— But it sounds like "As poor as it gets".
Here is (completely unscientific) comparison of DXO sharpness score vs. release year for genuine Canon EF glass (white) and Sony FE (red). Two 24-105 offerings from Canon are looking quite sorry even in comparison to infamous Sony's 24-240mm ultrazoom. Moreover, the 24-105/4L II is the least sharp of recent Canon lenses.
Allow me to consolidate Canon 24-105 lenses reviews from that site:
"Quite sharp" is the answer, about the same as or slightly better than the Canon EF 24-105mm f/4L II lens.
The image quality comparison between these two lenses shows mostly similarities. The RF lens is slightly sharper with very slightly less linear distortion and the EF lens has less vignetting.
Overall, the Canon EF 24-105mm f/4L IS II Lens compared to the version I lens shows the two more similar than different with the new lens showing a slight advantage at 105mm and the two trading small wins in other comparisons.
So as I mentioned in other threads no serious improvement in similarly priced RF lens vs EF L lenses.
In my opinion the only serious improvement is the IS improvement across the models: from 3 stops to 4 stops to 5 stops. This is usefull when shooting at museums, churches, etc and we have no second
fixed/brighter lens with us. Nothing else!
Yeah, gotta be one of the few times I’ve been truly disappointed with Canon. If they brought it up or close to the performance level of the 24-70mm lenses, I would have been ok with a $1500 price tag.
An RF 24-105 that gave the EF version a run for its money would have been another hard sell for the RF system and Canon - but I guess it is somewhat smaller @ same quality so there’s that...still a tempting combo I have to admit.
So, once again, I'll have to wait for the next version, me too, I would rather spend more on a higher quality version (1500 $ seems realistic).
The 28-300 is quite disappointing too!
I had that lens for a short while and found it ok considering the range. IQ wasn’t even the biggest issue I had with it - it was its conspicuousness particularly at events where such a lens is typically useful. Not to mention it is large and heavy, and the IQ it produced wasn’t necessarily a huge step up from a smaller kit (although the 6D I had it attached to extended its usefulness by being so awesome at high ISO, it was even useful for night shots!) BUT - I got so many shots with it that I wouldn’t have otherwise - being able to go straight from wide shot of a band playing to close up of the lead singer in less than a second is something I kind of miss to this day...
Ultimately though I took the path of better IQ.
I was okay with my EF 24-105/4 IS (MkI) on my 5D, 5DII and 6D, but am very happy with that lens mounted on my 5DsR. It is my go to lens for weddings and events, and for hiking when I accept the additional weight over the M3. For group or single portraiture I prefer my 35 and 85.
First of all, the usual one copy of one vs one of another, with no allowance for copy variation.
Secondly, what you are looking at for the RF vs the EF and the Sony vs Canon are the differences between the whole systems of different mpx sensors and processing of images and lenses, not just the lens. TDP links to a comparison of the 24-105mm RF on the 30mpx AA-filter EOS R vs the EF II on the 50 mpx AA-filterless 5DSR. The DxO mark scores depend on the sensor and camera as you can see by choosing different bodies in the comparisons.
If you really want to compare lenses, wait for Lensrentals to look at 10 copies of each using an optical system that is independent of any sensor or body.
Combine that with several online reviews I've read/watched, which generally seem to like it a lot, this seems like a very good lens to have in the RF arsenal.
I also owned the EF24-105/4L, used it on 5D and 6D. The quality was OK for zoom lens, but not up to standards of consumer-grade primes, like 50/1.4, 40/2.8 and Tamron 45/1.8. But this lens is 13 years old, and now it's 2018. The modern RF24-105 lens should have been very good, or, alternatively, it shouldn't have been granted the L badge.
They are different and designed with different EF/RF flange distances in mind.