EF 100-400mm f/4.5-5.6L IS II USM Review WOW!

Lots of atmospheric distortion. The truck had 2 jets engines and the driver wore 2 fire suits. The sun was in front of us a well

digital paradise wrote in post #18658151
I was not smart enough to stay indoors. Went to the local air show. With the Humidex it got to 43 Celsius (109 F). Wind gusts were up to 60 kil (37 mph). It was tough shooting. The wind was blowing me around.

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Very nice shots, wind gusts or not.

They had a race.

A few more. Not the best but I'll post because I almost melted out there

digital paradise wrote in post #18658151
I was not smart enough to stay indoors. Went to the local air show. With the Humidex it got to 43 Celsius (109 F). Wind gusts were up to 60 kil (37 mph). It was tough shooting. The wind was blowing me around.

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Nice shots of the planes!

But I just wanted to point out that the Humidex is not an actual temperature. And notice that they NEVER figure in the wind chill factor in the summer lest it diminish the drama of the skyhigh quasi-temperature numbers.

Just to add to the conversation. Today I also shot with my 5D4, 400 DO II and 2X. Tough on moving targets. Keeper rate was pretty bad but the conditions were not great. Hard enough to keep 800mm hand held steady on a calm day. I felt like a sail in the wind. I have come back with BIF shots with that combo every time I have gone out. I posted some with the 1.4 on the 5D4 thread and I'm still looking for something to post with the 2X.

Something to consider purchasing/using a TC.

Change in lens AF speed with EF Extenders

This last point (directly above) has created sufficient misinformation that it warrants a separate explanation. With a 1.4x Extender attached, the amount of actual focus movement within a lens is reduced by 50%, in order to accommodate changes in actual subject distance. With a 2x Extender attached, the amount of movement of lens elements is reduced by 75%. Because AF systems are essentially computer-controlled to read and react to focus distance changes, the information must be modified so that the focusing movement (or sensitivity) compensates for the added presence of the extender. In the Canon EOS system, this is done by deliberately reducing drive speed when an extender is detected.


https://learn.usa.cano​n.com …14/ef_extenders​_pt2.htmlp

Archibald wrote in post #18658166
Nice shots of the planes!

But I just wanted to point out that the Humidex is not an actual temperature. And notice that they NEVER figure in the wind chill factor in the summer lest it diminish the drama of the skyhigh quasi-temperature numbers.

Actual was 36.

digital paradise wrote in post #18658171
Actual was 36.

Which is still very high. It was 34C here.

digital paradise wrote in post #18658169
Change in lens AF speed with EF Extenders

This last point (directly above) has created sufficient misinformation that it warrants a separate explanation. With a 1.4x Extender attached, the amount of actual focus movement within a lens is reduced by 50%, in order to accommodate changes in actual subject distance. With a 2x Extender attached, the amount of movement of lens elements is reduced by 75%. Because AF systems are essentially computer-controlled to read and react to focus distance changes, the information must be modified so that the focusing movement (or sensitivity) compensates for the added presence of the extender. In the Canon EOS system, this is done by deliberately reducing drive speed when an extender is detected.


https://learn.usa.cano​n.com …14/ef_extenders​_pt2.htmlp

Yep, but note that if the distance to travel is half, and the speed is also half, then the time required is the same as before.

And in Rudy's blog, that is what he concludes. Yet most of us experience slower AF when using a TC.

Archibald wrote in post #18658173
Which is still very high. It was 34C here.

I struggled walking back to the vehicle lugging all the gear.

Archibald wrote in post #18658175
Yep, but note that if the distance to travel is half, and the speed is also half, then the time required is the same as before.

And in Rudy's blog, that is what he concludes. Yet most of us experience slower AF when using a TC.

Defiantly slower with a 2X. Fist thing I noticed first time I put the 2X on. A new challenge. Some say that the 1DX II does better.

digital paradise wrote in post #18658163
A few more. Not the best but I'll post because I almost melted out there

Was a 104.9°F at my house yesterday, luckily the humidity was like 10%, Mojave Desert dry heat. I stayed indoors.

Archibald wrote in post #18658175
Yep, but note that if the distance to travel is half, and the speed is also half, then the time required is the same as before.

And in Rudy's blog, that is what he concludes. Yet most of us experience slower AF when using a TC.

AF speed

A sharp lens that is slow to focus is of no use to me as I like to capture birds in flight. Prior to the introduction of the EOS-1D X, Canon electronically slowed down the AF servo drive speed when either 1.4X or 2X extenders were attached to account for the loss of light, that is as 50% with the 1.4X extender and 75% with the 2X extender. The significant reduction in servo drive speed, especially with the extender 2X, limited its application for bird in flight photography. Canon changed this equation with the introduction of the EOS-1D X and series II super-telephoto lenses. When using a series II super-telephoto lens and a series III extender, the EOS-1D X user will not notice a reduction in the servo drive speed with either 1.4X or the 2X extender. (Note that is not true for any other camera or lens combination that I have used). This means that when attached to an EOS-1D X, the EF 400mm f/4 DO IS II plus EF Extender 2X III can potentially be a great combination for shooting birds in flight.


http://arihazeghiphoto​graphy.com …ttle-of-the-light-lenses/

digital paradise wrote in post #18658147
You won't have AF with the 2X.

You may have AF in LiveView mode. Give that a try.

chuckmiller wrote in post #18658468
You may have AF in LiveView mode. Give that a try.

I've give that a try just to see. I can't see using it much.