topic Re: EOS 90D AF points differ depending on lens in EOS DSLR & Mirrorless Cameras

EOS 90D AF points differ depending on lens

mets — Fri, 20 Dec 2024 13:25:41 GMT

Hello,
My Canon 90D connecting to Canon EF 100-400mm f/4.5-5.6L IS II USM.
When pressing the AF method button ( see image 1), the screen displayed the right and left blocks blinking ( image 2, circled in green).
After replacing the EF with the kit Len, the result was normal. (image 3).
Images 2 and 3 were different.
What went wrong?
Please help
Thanks
TS

Re: EOS 90D AF points differ depending on lens

kvbarkley — Fri, 20 Dec 2024 13:38:05 GMT

There is nothing wrong. From the manual:

I am too lazy to get the "Supplemental Information" PDF, which is separate from the manual.

Re: EOS 90D AF points differ depending on lens

deebatman316 — Fri, 20 Dec 2024 14:40:39 GMT

Your camera is working correctly not all lenses support all AF Points. The manual list lens groups. Depending on the lens only certain AF points can be used. My 5D Mark IV does the same thing when I attach different lenses. Old Arc Form Drive AF motor lenses from the early days of the EOS system are classified as F/8 lenses. Even though the aperture is wider than F/8. No EF lenses released by Canon had an aperture smaller than F/5.6. The AF motors in these lenses are very slow. That’s why they’re classified as F/8 and only certain AF points can be used. Also these lenses are LIMITED to 3-4 FPS max in Servo AF. This is because the AF and aperture control happen sequentially instead of at the same time. Also the communication speed between the lens and camera body are slow. Even if you use Continuous High shooting the camera will automatically slow down to match the lens’ speed.

Re: EOS 90D AF points differ depending on lens

mets — Sat, 21 Dec 2024 03:31:50 GMT

Hi Demerits

Thank you.

Learned something.