EOS R50 compatible with EF 200-400mm lens, EF Mount Adapter, and Extender EF 2x?

[Kaplang]

Am I asking for trouble if I use a Canon zoom 200 - 400 mm EF lens on an EOS R50 body using the Canon RF to EF converter and a Canon 2X EF Teleconverter?
I’m hoping for no issues. What’s your take?
This will be for surfing photography on a good tripod.
Thank

[Original text restored.]

[johnrmoyer]

I use EF100-400mm f/4.5-5.6L IS II USM +2x III with the Canon Mount Adapter EF-EOS R. This might not be what you are planning to use.

When using the 2x extender, the aperture will be half the size so there will be less light. There will likely be more small aperture diffraction blur, but the free to download Canon DPP software can fix that if you tell the camera to save raw files. At a long distance across water there will be distortion from the light traveling through varying air densities. There will be some loss of contrast for fine details.

But you will have 4 times as many pixels on the subject.

An example of how I use it: https://www.rsok.com/~jrm/2022Oct07_birds_and_cats/2022sep28_egret_IMG_0469c.html , the egret was about 120 meters away.

A Great Egret (Ardea alba) was sharing driftwood with a pond slider turtle (Trachemys scripta) at Lake Thunderbird in Norman, Oklahoma, United States on September 28, 2022.

[rs-eos]

Four times less light with a 2x extender. A 1.4x would be one stop.

[Kaplang]

Guess my question wasn’t clear. 
let me try again. 
What is better about the 2X III then the plan 2X?Let me throw in the 2X II also. I just want to know how they differ from each other because cost is a  factor and I don’t want to pay for anything I don’t need in the technology. 

The lens I will be using with it is a Canon Zoom EF 200 - 400 1: 4.5 - 5.6 L IS Ultrasonic 

Thanks

[johnrmoyer]

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@Kaplang wrote:

Guess my question wasn’t clear. 
let me try again. 
What is better about the 2X III then the plan 2X?Let me throw in the 2X II also. I just want to know how they differ from each other because cost is a  factor and I don’t want to pay for anything I don’t need in the technology. 

The lens I will be using with it is a Canon Zoom EF 200 - 400 1: 4.5 - 5.6 L IS Ultrasonic 

Thanks

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MTF charts for the Extender EF 2x III are at https://personal.canon.jp/product/camera/ef/extender-ef2-iii/spec

When the version III was released in about 2010 it was said to be much better than the version II. Version III is heavier and has more lens elements than version II.

There is a review at: https://www.the-digital-picture.com/Reviews/Canon-Extender-EF-2x-III-Review.aspx 

[p4pictures]

Just trying to check the lens you described... the closest I found was the EF 200-400mm f/4L IS USM Extender 1.4x which if you drop in the built-in extender becomes a 280-560mm f/5.6 lens. 

If you add a EF Extender 2x III then it will get you to a 560-1120mm but the aperture will drop a further 2-stops to f/11. Normally I would not recommend combining a 2x extender with this lens, and you may find that only a limited part of the image area will be available for AF.

There is an image quality improvement of the 2x Extender Mk III over the older versions.

[johnrmoyer]

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@p4pictures wrote:

Just trying to check the lens you described... the closest I found was the EF 200-400mm f/4L IS USM Extender 1.4x which if you drop in the built-in extender becomes a 280-560mm f/5.6 lens. 

If you add a EF Extender 2x III then it will get you to a 560-1120mm but the aperture will drop a further 2-stops to f/11. Normally I would not recommend combining a 2x extender with this lens, and you may find that only a limited part of the image area will be available for AF.

There is an image quality improvement of the 2x Extender Mk III over the older versions.

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With DPAF, I expect that the entire sensor will be available for AF even with low light levels.

https://cam.start.canon/en/C011/manual/html/UG-06_AF-Drive_0060.html#AF-Drive_0060_3

But the manual also says "Accurate focusing may not be possible at high aperture values or depending on the lens, the distance to the subject, and how fast the subject is moving."

[rs-eos]

You have since edited your discussion to just be "?".  What is the question you are seeking answers to?

[Danny]

We've fished out the deleted text and restored it. 👍