RF 24-240mm versus RF 24-105mm < Both mounted on EOS-R + Battery Grip
I have shot about 600 images on the 24-240mm most of which were a recent full day at an agricultural show and I have owned and used the 24-105mm for about a year. I only shoot RAW. The weight and size differences between the two lenses are negligible.
Whereas in the context of my personal preferences each of the two lenses has its pros and cons, I find that the cons of the 24-240mm are a deal breaker and so regretfully it is probably about to be returned.
The deal-breaker is that I am simply not at all happy to live with any lens which has such appalling vignetting when shot at its widest focal length (24mm in this case) and furthermore to have to restrict the choice of aperture values to reduce the vignetting is not an acceptable solution. Neither is it acceptable to have to crop the image composition in post-processing. It might be slightly more palatable if you could actually see the vignetting whilst shooting and therefore adjust the focal length but you can't.
IMPORTANT UPDATE:
I have had a long phone chat (they rang me back) with Canon Tech Support about the vignetting and they are aware of it and inform me that it is only evident in RAW files, not JPEGs, and that processing the RAW files in Canon DPP software will solve the issue. The vignetting is a compromise in order to avoid compromising other onboard and lens design features. No-one knows if a future firmware update would solve this problem which is unique to RAW because RAW is naked data captured by the sensor - As it's already solvable in DPP I think it unlikely that Canon will solve it in future firmware. Chatting with WEX it seems that there is an unfortunate modern trend from all camera manufacturers to solve such issues in offboard rather than onboard software.
Such vignetting is apparently very common on superzoom lenses and not exclusive to Canon's.
This vignetting issue is very disappointing in what would otherwise be a very practical and flexible lens. The photographer Christopher Frost has made a full review of each of the two lenses and covers what I would have written plus much more about the detail.
The reviewer very comprehensively illustrates the vignetting from about 5:50 in this first video :
View: https://www.youtube.com/watch?v=PLk7GsbPye0
View: https://www.youtube.com/watch?v=dYaPpqmkZms
So I may be going to go back to having my RF 24-105mm + EOS-R ready in my Lowepro holster and my EF 100-400mm L + 1DX-2 on my cross chest strap. An unexpected disadvantage of trying to politely get a shooting position with just the R combo visible is that I look just like another member of the public and no-one gives way, whereas a big white telephoto lens and two cameras gives people the impression that you are a serious professional and they don't want to interfere with you trying to do your job.
In summary I would say that the RF 24-240mm is very practical for casual use and particularly with the EOS-RP, but there are reasons why it is much cheaper than the RF 24-105mm L.
SHIRE HORSE 'CAPTAIN' LIKES A DRINK AFTER A HARD DAY'S WORK by
Robin Procter, on Flickr
'CAPTAIN' THE SHIRE HORSE by
Robin Procter, on Flickr
WALKING THE COURSE by
Robin Procter, on Flickr
^ Am I being sexist if I call this last photo nice 'eye-candy'? Nah, just being heterosexual.
In due course I'll post some more images shot on the RF 24-240mm.