EF Extender doesn't seem to increase zoom on EOS R6 Mark II with EF 70-200 L

[gokelgo2]

So my dad was shooting with an EF Extender on his R6 mII. He has his adapter-extender-EF 70-200mm L series (not sure on the specifics but shouldn’t matter at this point.)

Shooting raw, but it doesn’t seem like the Extender was actually doing anything to increase the zoom.

Are we doing something wrong?

[johnrmoyer]

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@gokelgo2 wrote:

So my dad was shooting with an EF Extender on his R6 mII. He has his adapter-extender-EF 70-200mm L series (not sure on the specifics but shouldn’t matter at this point.)

Shooting raw, but it doesn’t seem like the Extender was actually doing anything to increase the zoom.

Are we doing something wrong?

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Need more details.

Canon EF to RF adapter?

Which extender?

In free to download Canon DPP software it will tell you the focal length when you load the raw file. If running Linux, then I like Rawtherapee for this purpose, but others like Darktable.

I use "Mount Adapter EF-EOS R" and often use "Extender EF 2x III" or "Extender EF 1.4x III".

An example with EOS R5 and "EF100-400mm f/4.5-5.6L IS II USM" and extender ( also at: https://www.rsok.com/~jrm/2025Mar31_birds_and_cats/2025mar24_hawk_IMG_3140c.html  ) :

Red-tailed Hawk (Buteo jamaicensis) at Lake Thunderbird in Norman, Oklahoma, United States on March 24, 2025 ; EF100-400mm f/4.5-5.6L IS II USM +2x III ; Focal Length 800.0 mm

[jrhoffman75]

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@gokelgo2 wrote:

So my dad was shooting with an EF Extender on his R6 mII. He has his adapter-extender-EF 70-200mm L series (not sure on the specifics but shouldn’t matter at this point.)

Shooting raw, but it doesn’t seem like the Extender was actually doing anything to increase the zoom.

Are we doing something wrong?

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The extender is just a magnifying glass, so there is no way that it will not magnify the image.

What makes you think it wasn't doing anything?

[ebiggs1]

Show us two shots one with the extender and one without.

[ebiggs1]

Raw has nothing to do with it.

[normadel]

That's not possible. Are you misstating what you see/want?

A tele-extender (if that is what you are talking about)  is a magnifier. The only way it would not increase magnification is if you took out the glass in it. Then it would be an extension tube.

So, what do you mean by "adapter-extender"?

[ebiggs1]

"Then it would be an extension tube."

"That's not possible.", either as I doubt it would focus on anything beyond a foot or two.

[deebatman316]

I'm not even sure if the OP is using a teleconverter. I've seen a lot people call the mount adapter a teleconverter but its not. All it is is an extension tube that puts the EF/ EF-S lens at the correct distance from the image sensor. Did you notice the OP called it an "adapter extender".

[normadel]

Maybe the OP is using an EXTENSION TUBE, not a teleconverter (tele-extender).

Alas, we'll never know unless OP can be more clear.

[jrhoffman75]

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@deebatman316 wrote:

I'm not even sure if the OP is using a teleconverter. I've seen a lot people call the mount adapter a teleconverter but its not. All it is is an extension tube that puts the EF/ EF-S lens at the correct distance from the image sensor. Did you notice the OP called it an "adapter extender".

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OP does state “EF Extender”. 

“adapter-extender-EF 70-200mm L” could mean the three items in a row, which is how they would mount on body. 

Bottom line - more clarification needed and OP seems MIA.