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Canon R7, Ef 100-400 ii and 1.4 Tc Bif Photos. Are these acceptable?

Started 1 month ago | Questions thread
Victor Engel Forum Pro • Posts: 20,968
Re: Canon R7, Ef 100-400 ii and 1.4 Tc Bif Photos. Are these acceptable?
2

Ephemeris wrote:

Victor Engel wrote:

Ephemeris wrote:

davel33 wrote:

"So 1.4 tc doesn't improve iq"

There is NO extender 1.4x or 2.0x that will improve iq.

It only makes the image bigger.

There is a difference

I fell for that same trap.

It could help your AF get an in focus shot?

Or it could hinder, if the focus sensors require a wide aperture to work well.

Becuase of the amount of light? Not sure I quite follow.

It has nothing to do with the amount of light. Cameras using phase detection to focus (see https://en.wikipedia.org/wiki/Autofocus) rely on rays traveling through the lens at some distance from the center. The more accurate sensors require f/2.8, one of the reasons there are so many f/2.8 lenses. Adding a TC, you reduce, possibly, the number of focus sensors available for focusing. because those sensors can't see through the lens. This doesn't apply to contrast detection focusing.

Cameras like R5 and R7 that use dual pixel technology for focusing require a certain minimum aperture. With the recent introduction of several f/11 lenses, I'm guessing it must be slightly smaller than f/11. If I'm right, the dual pixel focusing would not work with one of those lenses plus a TC.

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Victor Engel

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