Lens compatibility with 90D

[timmyleeturner]

I was wondering if there were any known issues between the Canon 90D and the 

Canon EF 70-300mm f/4-5.6L IS USM Lens.  I've worked on obtaining sharp focus for about 6000 pictures and cannot accomplish it.  Switch to the new 18-135 Nano and they are tak sharp.  Switch the lens back to my old 70D, tak sharp.  I've tried every setting I could find related to focus. Over exposure is a serious problem too, I'm sending it back to Amazon if there are no known issues.

[mplaforest]

After multiple emails and phone calls I was able to reach someone Canon Engineering support group to discuss an issue with my new Canon 90D. At first I thought the issue was a lens compatiabilty issue, but after reviewing the pictures exif information, it was determined the camera and the lens are compatiable. The issues (bug) is with the flash mode, which prevents the camera from communicate properly with the lens. Basically when I turn the flash on, the lens camera thinks the 105mm lens is a 24mm lens. Turn off the flass and everything is fine. The technician I spoke to said they are aware of this issue and it should be fixed in the next firmware release. He couldn't tell me when they are planning on releasing the firmware update, but thought it would be soon. 

[timmyleeturner]

I'm calling them today about my concerns with exposure and focus at 300 with my lens on the 90D

[mplaforest]

I had to make several calls to the service center and finally found someone who put me through to a manager, who then routed me to an engineer.