Excellent video on birds in flight, love taking pictures of shore birds and bald eagles, I live in St. Clair ,Michigan

Very nice video. My settings are Manual with Auto ISO on my D 7000 Nikon. Is it better to keep a limit for the maximum ISO in Auto ISO, such as 1600/3200, as I feel very high ISO may affect image quality? Thank you.

Just a question if I am on tight budget would R10 suffice, or shall I try Sony

😂😂😂😂😂😂

Always like seeing your reviews,, but I can answer your "What's the catch " without doing so..... That's easy,, the price. Effectively it's a "professionals only" lens. That one lens costs more than my entire (amateur) camera bag of kit which includes an R5i, an R6ii, RF100-500m L IS, RF 24-105 F4 L IS, RF 16mm F2.8, RF 800 F11, RF 100mm macro F2.8,,, all of which still doesn't add up to the price tag for that one lens. I'd like one,, of course,, but that will have to remain a unfulfilled fantasy.

Perfect focus on two subjects that are not in tandem is simple, correct distance in focal plane and correct angle. No need to stack.

For me the catch is the price, yes would be nice if I ever win the lottery 🥳

Thanks!

I can’t tell by watching the video but did cannon lend you the lens for purpose of review?

Jan, i tested my R6 II with this setting so i share if anyone want to try, in PINK menu, 1. AF area: 3rd option (1st Expand AF area), somehow gave me sharper images especially when focus pointing on lights 2. Switching tracked subjects changed to +1 3. to prevent looking for R/L eye changed to right Eye only, less stress for hunting eyes. 4.Tracking sensitivity and Accel./decel. tracking Both to max. + to the right, useful to track birds in-flight, sudden movement and pre-capture.

i just love this Lens i own one ....Image Quality good at all range Background blur beautiful and like you say Fast and good autofocus and Image Stabilasion superb and it suprized me how good she works with TC i have both and they both give me super quality on this lens...My friend has a 2.0x Tc wich does not show good images on his RF400 f2.8 but if he use mine it gives better image quality so i think Canon has to be take a quality check on their TC´s as they seem to be either supersharp or a Soft

I am a total amateur but love the thrill of bird/wildlife photography. I currently own a 5d mkiv and love it. I pair it with an ef 400mm f4 or Sigma 150-600. I am on the fence with the big canon 600mm so this video, from a trustworthy source, has been VERY helpful!

I like that Canon is experimenting with unconventional zoom ranges and optical formulas. I just wish they would allow Sigma and Tamron to offer their lenses in RF mount for full frame. Most photographers can't afford these very expensive first-party lenses.

I shoot sports, primarily baseball and softball. I was originally shooting with a 70-200mm f2.8 and a 100-500mm, but a year ago I decided I wanted to upgrade. I rented the 100-300mm f2.8 and the 400mm f2.8 and used them both for a week. For me, the 400mm f2.8 was the no-brainer choice between the two -- the extra reach and the overall look of the images was just really special. A two-camera setup with the 70-200mm f2.8 and 400mm f2.8 gave me both the best image quality and greatest flexibility. For a cheaper (but still not cheap) option, I'd probably go with an APS-C camera like the R7 and the new 70-200mm f2.8 Z lens, as that gives you an equivalent 112-320mm focal length range, and as a bonus the new Z lens accepts teleconverters if needed and seems to perform very well with them.

I'm a beginner and have picked up an old 5d mk3 and plan on getting a few good L lenses, but if or when I ever go mirrorless I will definitely rather go with nikon over canon or sony. Their update policy is amazing, the fact that they let 3rd parties make lenses is another huge bonus, unlike canon. Until then I hope to learn a lot on the 5d3, it's amazing coming from a 5yo phone and a decade old superzoom from nikon(the l320 which no one's hear of probably cause it went for 300 dollars or something so it was a cheap big zoom thing with atrocious iq).

Extremely helpful info, Jan. Thanks for sharing this!

never buy first few versions 😂

Definitely on my wish list. I'm going to rent it later this year.

by all reputation, a great sports lens, but not good for birding. Would be good for safari wildlife though with the 1.4x TC. Very disappointing 2x TC performance, but not unsurprising imho. You just can't beat a good 600f4 prime. Probably cheaper than the 100-300 too.

I don't quite agree with you, at Nikon the Zf has the same autofocus as the Z8 and 9, with bird detection which the Z6iii doesn't have. Which makes an excellent alternative to the Z8 and 9. As for Sony, the a6700 APS-C is an excellent combo with the 200-600. These two examples are at the same price as the Canon variant, especially since the 200-800mm RF remains the most expensive of the 3.

EF 300 II has 2 pieces of fluorite and RF 100-300 cut that down to 1. I'm sure Canon tried hard to compensate that with UD glass but the subtle difference could be what causes the 2x performance drop. Just my guess.

The sony 300mm is the only lens i know that plays well the 2x across all brands ,its just physics i guess ,but fair play to canon for a nearly all in one lens ,but imagine if some one designs a lens with built in t/c options of 1.4 & 2.0 x and a bright large aperture zoom ,we would be at a point of one lens does it all .Still not sure why sony can get their ois to work as good as others their ibis is very good but probably not as useful on long telephotos ,where you become more reliant on ois ,although is this more a issue in video where as for stills i hear no complaints .

I have the RF 2x TC also, and I find it soft on the 100-500mm lens also. It's a very disappointing piece of glass.

Many thanks for the perfect sharing, Jan. So, that’s the reason why I expect 200-500 F4 so much and use internal APSC crop function instead of 1.4/2x teleconverter. I think this lens is more sports or indoors photography oriented, not dream lens for wildlife. 😊

One lens for the price of 4 100-500mm lenses ooof. I hope canon fills that gap with more options.

Your videos are exceptional. Thanks!

Great photos and review Jan!

Jan, another really informative video. My problem is, that the zebra settings isn't in the menu as you show it. I have updated the firmware, and I'm using an R5.

Atleast tell the filter name rather than expensive or cheap

It’s a shame that with the 2.0X teleconverter, this lens does appear to be just a little softer than what is ideal for something with fine details like bird feathers - especially if cropped or enlarged. But, I bit the bullet last year to swap out my EF 300L f/2.8 II lens for this one for motorsports and it’s extremely sharp for this kind of work. I really enjoyed the images I got with this combination and was very pleased with its sharpness. Was it the most crispy weapon? Perhaps not 100-500 sharp, but still quite good with beautiful bokeh falloff. I was certainly a hater of this lens when it was released because my main complaint I would like to have seen remedied from the previous EF version was the weight - I dreamed of a tiny little RF 300. Unfortunately, Sony answered that want. But wow…the versatility of setting off for the day with a RF 24-105 f/2.8 and the RF 100-300 f/2.8 and both teleconverters covers you for nearly everything you can throw at it during a Motorsport race. (Save for the artistic ultra-wide or more extreme low light shots.) I still think primes are king for wildlife. If you treat this 100-300 as a prime zoom for subjects that fall within that field of view, it’s a superb lens.

Great, unbiased review, as always. Considering that I would have to add a teleconverter to get beyond 300mm (plus the hefty price tag) convinces me to "suffer" by hanging onto my 100-500 and 200-800 lenses -- with no regrets.

❤❤❤

Jan, thank you for yet another great review! I understand that this may not be the ideal lens for those who more often than not find themselves short on the long end. I am looking forward to someone doing a field review with mammals in some national parks in India or Africa. The big cats are my preferred subjects. And I would love to travel with just one lens if I am told that I would not miss the 400 2.8, which I have not had the courage to acquire. Till that time, I shall hold on to my 100-500 and may be continue to miss out on more of the great golden and blue light shots!

I'm not sure. I have several of the EF primes and zooms and they are so good, I'm not at all sure it's worth investing in this one for my case.

Makes a clear case for the 400 f4 DO in RF to return

Great info! Thanks for taking me along!!

Unrelated question: how do you set up the R5ii to record video while taking photos ? how can I do that ?

There was a European wildlife photographer who's review I watched last year when deciding if I wanted this lens. His side by sides showed noticeable image degradation with both teleconverters, though much worse with the 2x, with results worse than the slow 100-500 L, which put me off considering the price of the lens, the price of Canon's very average teleconverters, and given that I never really need a 300mm focal length. I either want longer or shorter. I'm strangely glad your review didn't contradict his and he didn't just have a bad copy.

Interesting video, Jan, but at these prices the R1 and the 100-300 are not attainable for me. It’s just camera porn really.

Nice video Jan. Would love to see a video comparing the r7 with the 70-200mm. Yes, of course the depth of field will be about 4.5 equivalent but I just wonder how it would perform. Actually might have to wait for the r7ii to do it but I’d definitely be interested. I think an r7 with the new RF 70-200 USM Z could bring amazing value and give similar reach. That 100-300mm is just too expensive.

24mp does not seem to fit the price point and as a "Flagship". Not a clear win for sure.

I’ve owned and used this lens for a year, almost exclusively shooting wildlife. I find it incredibly sharp, even wide open, outstanding IS and easily hand holdable. Attached to my R3, focusing is phenomenally fast and accurate with sufficient light. Focus accuracy suffers ever so slightly in low light with furry, low contrast subjects, but given enough light and a contrasty subject, it’s a focus accuracy beast. Image quality with the 1.4x TC is slightly less sharp, but acceptable and easily fixed in post. The focus speed and accuracy is not affected with the TC. Yes, it is an expensive piece of glass, but it is a game changer when shooting wildlife in relatively close quarters. No regrets investing nearly $10k.

From the sound of it if you are working beyond 600mm at f8 on the 100-300mm you might just be better off getting the Canon RF 200-300mm? Or get the older 300mm f2.8 V2 as with the EF 2x TC III is really sharp at f5.6 even with my R7 crop sensor as long as the focus is on point. 😊 IMHO

The price is the catch.

Love your review... But i need to ask you this. I'm not sure what to buy in 2025: 5d mkiv (i know it's old tech) or this r6 mkii. I just do photography (all kind) and not video... But I'm not sure about the electronic viewfinder coming from traditional slr photography since 30y! I love the quick eye/tracking autofocus of this r6 mkii... But i just love to use the viewfinder and not the LCD screen. I have a lot of EF glass and im a Canon (old) boy

Excellent review Jan, always appreciate your honest no bias attitude and practical application.

Yes, please cover Sony too.

A friend of mine has this lens! He loves it! Well, loved. It caught a bad case of glass fungus 😅

I shoot Nikon (mostly because of lenses like the 4/600TC) but the RF 2.8/100-300 (and the 4/10-20) are two lenses I wish Nikon had as well in a native Z-mount version. Or even better, a 2.8-4/100-400TC). I guess Nikon is working on some fast telephoto zooms because this is currently missing from their line-up. And Canon has some really cool patents for long zooms. I think Canon should have added a built-in 1.4 TC, it would not have added that much weight but would have made the lens even more flexible.

really glad you did this review and as always made a good job of it God bless you :) with a 1.4x would you use this over the 100-500 ... how would the background separation compare? seems like it would pair well with a 600 f4 and r1?