The 3.5-5.6 100-400 RF would be 2/3's of a stop faster than the current EF model. 3.5 to 4 is 1/3 stop and 4 to 4.5 is another 1/3 of a stop. Not a lot but there are times when every little bit helps.
And every little bit less can help too. I measured up my current model EF 100-400 L ii and it came to 238 mm from the film plane at 100 mm and 312.5 from the film plane at the long end, versus 204.85 and 291.30 from the film plane for the RF patent lens. So, a little over an inch shorter at the short end and about 3/4 inch shorter at the long end. Not bad.
My thought exactly. There has to be something around 18-55 to sell for pretty cheap as the kit lens for this new RP. The f4 lens on the R is to expensive and the 24-240 seems like it would be an upgraded kit at best.
f/3.5 is only 1/3 stop faster. [...than f/4.0 ]
Thanks, guys, for pointing that out and showing my lack of precission3.5 to 4 is 1/3 stop and 4 to 4.5 is another 1/3 of a stop.
I doubt if having f/5.6 throughout the range will make it significantly lighter. The size of the front element is determined by the f/number at the long end, not the short. Narrowing the short f-number won't narrow the diameter of the 400mm f/5.6. f/6.3 at 400mm would shave off significant weight.As a current 100-400ii owner,I have been curious to see what the RF version would bring. Reduction in size at the wide end is appreciated. 2/3 stop increase at the wide end won’t be very useful for me, and dare I say for most users. I have no idea what that costs in terms of design, but I would be happy with f/5.6 throughout the zoom range if it saved some size or weight.
Oh well, some day I’ll own the RF version, but only after I can get it used and the extenders are available.
When I leave my pro gear at home and go out hiking or for a walk in Venice i always put the cheap and compact EF 55 200 "USM" in the bag, the focal length is so "comfortable" on FF , also great for traveling (compact and very light and cheap, again) and surprisingly fairly good and quick AF for the price.
Could be a great lens; I already like the 100-400 II adapted better on the R than on my 5D IV . Just seems to be a bit more accurate with focus. Superb combination with a 500 or 600mm for wildlife.
So the big difference is the aperture at "wide":
EF 100-400 4.5 -5.6
RF 100-400 3.5-5.6
Do you have either of the extenders? I'm wondering how the lens plus extender plus adapter feels to shoot with.
Am I correct to assume that telephoto (and telephoto zoom) lenses do not necessarily need major design changes to be ported from EF mount to native RF mount? I would really like to see Canon bring to market some fast wide primes for the RF mount. Is coming up with a fast-wide prime for RF simply a more difficult engineering/design project, or is Canon waiting for customized sensors for the RF mount that have better support for wide angle lenses?
What is the advantage of using a native RF mount telephoto lens compared to using an EF telephoto of same focal length and aperture with an EF-RF adapter? There shouldn't be any advantages in terms of the length or width of the lens. Perhaps better mechanical stability and slightly less weight?
Once to market, it will be interesting to see at which focal lengths the max aperture changes - I suspect there may be some gains there too. (As in the max aperture holds a little bit longer as one zooms the lens towards the long end. We shall see.So the big difference is the aperture at "wide":
EF 100-400 4.5 -5.6
RF 100-400 3.5-5.6
and obviously the size and weigth.
I think the general discussion about the long backfocus of tele could not be applied to zoom and different zoom optical designs can take advantage of short backfocus
The performance of the lens at 560mm depends on both the extender and the lens. I have had 3 1.4xTCs and 3 100-400mm IIs. My present ones pair really well and are excellent wide open.Yeah the 1.4 extender but I don't use that with the 100-400 anymore; in that case I grab the 500. I know that on the R, the 500 plus extender performs well.
In the past I've shot the 100-400 with extender and that works ok, although slightly stopping down is a requirement. You're talking about f/9 then or even further.