Patent: Canon RF 100-400mm f/3.5-5.6L IS and more

Asher

EOS M50
Jul 4, 2016
33
1
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.
Ah, you're right. For some reason, I was thinking the current lens was f/4.0 at the wide end.
 

knight427

EOS T7i
Aug 27, 2018
78
89
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.
 

criscokkat

EOS 80D
Sep 26, 2017
152
111
Madison, WI
I'm intrigued by the 50-250 since that's generally an APS-C lens.
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.
 
Feb 8, 2019
1
0
A 100-400 RF was a major point that i was hoping would come out soon, but i'm still waiting for a 5D SR replacement in a mirrorless body and a few more RF lenses to come out. I'm pretty impressed with the speed at which they are coming out, but i really want to see some f/4 L lenses (16-35 f/4, 70-200 f/4, or similar to be exact), that are in a better price range than all these 2.8 lenses i see coming out. I'd really like to see the 100-400 be one of the two or three main lenses i take with me backpacking, so i'm hoping the RF version will be lighter and a bit smaller.
 

AlanF

5DSR
Aug 16, 2012
4,754
1,313
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.
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.
Interesting what you say about extenders. More RF kit to buy and more EF kit to lose value.
 
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Reactions: knight427

Ale_F

6D 7D
Nov 22, 2018
22
11
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
 

edoorn

EOS 80D
Apr 1, 2016
151
40
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.
 
Reactions: knight427
Feb 8, 2019
1
0
Italy
I'm intrigued by the 50-250 since that's generally an APS-C lens.
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 :D , also great for traveling (compact and very light and cheap, again) and surprisingly fairly good and quick AF for the price.

if an RF 50-250 will exist i'll have it for sure when i'll switch to the RF system
 
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dsut4392

EOS T7i
Jul 31, 2014
62
17
I'm intrigued by the 50-250 since that's generally an APS-C lens.
16-35 plus 50-250 would be a pretty tempting two lens kit for me, depending on how the relative IQ of the 24-240 pans out. My current travel kit with 6D is 16-35/4 plus Tamron 28-300. IQ of the Tamron is perhaps surprisingly OK, but still leaves me wanting more.
 

knight427

EOS T7i
Aug 27, 2018
78
89
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.
Do you have either of the extenders? I'm wondering how the lens plus extender plus adapter feels to shoot with.
 

degos

EOS 80D
Mar 20, 2015
137
70
So the big difference is the aperture at "wide":
EF 100-400 4.5 -5.6
RF 100-400 3.5-5.6
Don't get too excited by the aperture at the wide end until we see the drop-off with increasing focal length. The recent EF 70-300 IS II only has 7mm of length at its widest aperture before it starts closing-down, a bit of a con really but enough to get f/4.0 into the name.

The EF 100-400 II makes it as far as 130mm before closing-down to f/5.0 and doesn't hit f/5.6 until 300mm.
 

edoorn

EOS 80D
Apr 1, 2016
151
40
Do you have either of the extenders? I'm wondering how the lens plus extender plus adapter feels to shoot with.
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.
 
Reactions: knight427

slclick

5D Mark V
Dec 17, 2013
2,790
214
Wouldn't the wider aperture at the wide end lend toward a wider aperture focal length spread towards the long end?
 

FramerMCB

Canon 40D & 7D
Sep 9, 2014
333
41
51
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?
Caveat: I'm not an engineer. As I understand it, from reading what Canon's engineers (white papers) released about the new RF lenses. They are able to redesign lenses utilizing gains from the larger mount coupled with the shortened flange distance. I would think the R lenses could/can be a little shorter than their EF counterparts. The other gain, as seen in the other post concerning the proposed/rumored RF 100-400mm f3.5-5.6L IS... note the f3.5 that's a 2/3-stop gain at 100mm over the EF Mark II version (f4.5 compared to f3.5). Because of the larger diameter it sounds like the engineers can correct for certain lens aberrations that are inherent when passing light (different colors of the spectrum) thru the various elements in a given lens... It will be fun to see what Canon comes up with and if there are any design changes to some of the "consumer" lenses that make them better performers than their EF counterparts.
 
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FramerMCB

Canon 40D & 7D
Sep 9, 2014
333
41
51
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
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.
 

AlanF

5DSR
Aug 16, 2012
4,754
1,313
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.
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.
 
Reactions: padam

Kit.

EOS 7D MK II
Apr 25, 2011
751
307
Caveat: I'm not an engineer. As I understand it, from reading what Canon's engineers (white papers) released about the new RF lenses. They are able to redesign lenses utilizing gains from the larger mount
EF and RF mount diameters are the same, 54 mm.