R5 AF speed with 100-400mm f/4.5-5.6l is ii usm & 2x extenter iii

[AlanF]

And why wouldn't an ibis be stable in flight? ( https://en.wikipedia.org/wiki/Ibis )

Ibis at 1/3200s on a 5DSR + 100-400mm II + 1.4xTC. Remarkable how this antique equipment ever took BIF.

 

[Nelu]

Ibis at 1/3200s on a 5DSR + 100-400mm II + 1.4xTC. Remarkable how this antique equipment ever took BIF.

Yep, ibis does wonders!

 

[Mt Spokane Photography]

I can see that the AF is improved. But, I don't understand how the image quality can be improved. The IQ of the 100-400mm II drops because of the hit of the TC on the MTF values, which become more noticeable the higher the Mpx of the sensor. It just doesn't make sense to me that the IQ of the 100-400mm II + 2xTC gets magically better with R5 sensor. (I use the 100-400mm II, and have played with the 2xTC on it using liveview with the 7DII, 5DIII, 5DIV, 5DSR and 90D. It's pretty good and I will use it with the R5).

As a general rule, a higher MTF for any component in a system results in a higher overall MTF. The overall MTF is always less than the weakest link, so even if a lens is the weakest link, the overall MTF can be improved.

The system MTF is the product of the MTF of the individual components. So, just looking at two components (there are many), sensor and lens. If sensor is 0.7 and lens is 0.8, overall its a MTF of 5.6. You can play with those numbers to see the result.

 

[Bert63]

Just got my R5 last night and did some quick field testing today.

There wasn't much info about the AF speed for EF lens. So I have taken out my EF 100-400mm f/4.5-5.6l is ii usm and the 2x extender iii to try some bird in flight. The combo yield 800mm f/11 in aperture. However, it work very well for the bird eye tracking in continuous AF. And thanks to the IBIS, i can shoot at 1/500s and yield very stable result.

That's really a big improvement from previous EOS R. And that's not even possible with my 1DX.
Besides, the image detail is awesome with the latest sensor. The image quality with 2x extender and wide open aperture usually not impressive in previous models. I can tell you now it's greatly improved.

I am just another happy owner now

Any chance you’ll post some examples?

 

[AlanF]

As a general rule, a higher MTF for any component in a system results in a higher overall MTF. The overall MTF is always less than the weakest link, so even if a lens is the weakest link, the overall MTF can be improved.

The system MTF is the product of the MTF of the individual components. So, just looking at two components (there are many), sensor and lens. If sensor is 0.7 and lens is 0.8, overall its a MTF of 5.6. You can play with those numbers to see the result.

The context of my comment was that it was claimed that: "The image quality with 2x extender and wide open aperture usually not impressive in previous models. I can tell you now it's greatly improved." The 5DSR sensor is of comparable IQ to that of the 5R and the 90D and M6II are of higher resolution still. So, I still don't understand why this sensor magically improves the IQ of the 2xTC. As you point out, if it lowers the MTF to a value of 0.Z, it will lower all sensors by the same factor of 0.Z.

 

[heheapa]

100-400mm II + 1.4xTC is different. You can get f8 and it's one stop advantage. And we all know that 2x TC IQ can't compete with 1.4xTC.

Attached examples below for the 2x TC. reduced to 50% for the crop and still yield about 6MP.

 

[BeenThere]

Another question about R5 IBIS behavior. When using mode 3 IS on EF telephoto lenses, is IBIS turned on at the instant of the shot (like IS), or, is it always on?

 

[heheapa]

Another question about R5 IBIS behavior. When using mode 3 IS on EF telephoto lenses, is IBIS turned on at the instant of the shot (like IS), or, is it always on?

I am not able to choose the IS option in the menu. The IS On/Off is controlled via the lens IS switch.
I've tried the 100-400L with 1.4x TC with both EOS R and R5 and found the R5 is more stable, at least in the view finder. Not sure if subjective. And I do see the IS icon in the screen. So I don't know if IBIS kicked in.

I shoot with Mode 1 for the BIF. Attached an example with 1.4x TC. I can see the view finder is more vibrate with my handheld with mode 3. Probably can do some try with mode 3 for the BIF later.