Kenko Pro 300 DG 1.4 TC & Canon Primes - Question?

I just got a Kenko 1.4 TC. With my 70-200mm f/2.8, the camera reports f/4.0 as the maximum aperture, which I expected (one stop less). On my 100mm f/2.0, it reports f/2.0, and on my 50mm f/1.4, it reports f/1.4 as the maximum aperture. Is this correct function? I thought all lenses would report one stop less than the maximum aperture. If it is mis-reporting the f stop to the camera, will it still function correctly?
Thanks / Stan

You should be able to tell us if it works ok or not. Yes, everything is fine.

Michel Souris wrote in post #5043552
I just got a Kenko 1.4 TC. With my 70-200mm f/2.8, the camera reports f/4.0 as the maximum aperture, which I expected (one stop less). On my 100mm f/2.0, it reports f/2.0, and on my 50mm f/1.4, it reports f/1.4 as the maximum aperture. Is this correct function? I thought all lenses would report one stop less than the maximum aperture. If it is mis-reporting the f stop to the camera, will it still function correctly?
Thanks / Stan

We can trick the camera, but we can't trick basic laws of physics. A 1.4x TC costs 1 stop, plain and simple.

Michel Souris wrote in post #5043552
I just got a Kenko 1.4 TC. With my 70-200mm f/2.8, the camera reports f/4.0 as the maximum aperture, which I expected (one stop less). On my 100mm f/2.0, it reports f/2.0, and on my 50mm f/1.4, it reports f/1.4 as the maximum aperture. Is this correct function? I thought all lenses would report one stop less than the maximum aperture. If it is mis-reporting the f stop to the camera, will it still function correctly?
Thanks / Stan

All 1.4x TCs lose one stop, but the camera doesn't always display it. In order to report the correct aperture, both the lens and the TC need to be designed to do so.

In your case the Kenko TC is designed to report the corrected aperture, and so is the 70-200 lens, so that combination displays the correct aperture. Canon do not expect people to use a TC with the 100mm or the 50mm (a Canon TC will not fit on these lenses), so they are not designed to report the corrected aperture.