Focus Help!

I have a new to me 1dm4. I can't get it to focus right! I'm using center point metering and aiservo. Seems where I meter at isn't focused but everything else is. any suggestions? It's driving me nuts!

It might help if you post an example JPG (or three) as shot by your camera, resized smaller via postprocessing for posting on POTN, but otherwise containing all the original EXIF data recorded by the camera (not 'Save for Web'). Then we can start to analyze and/or ask questions about how the camera was set up, etc.

Since it's "new to you" and not factory fresh I would start by going into the control panel and instruct the camera software to reset to original settings and go from there.

Focused on the birds head. Bird is out of focus. The pole is not.
I reset the camera to factory and set it for back button focus.

Exposure parameters look to be fine, to rule out the issue of camera+lens motion causing motion blur. Examination of the photo seems to show the area behind the bird to be in sharp focus.
Did you change FL after focusing? that does not work with most Canon zooms as they are not 'parfocal', they are varifocal...focus changes with zoom.
Was the posted shot one of the first ones after 'reset to factory settings'?...you have not had an opportunity to correct for backfocus with this specific lens?

FL stayed the same. This was after a reset, What corrections for BBF? I have tried to micro adjust the lens. I printed off a focus chart and tried to adjust the lens. All the pictures looked the same at different settings. That picture is set at 0.

According to this procedure, your test target should be about 33' away for testing.

https://cdn.static-bl.com …AF-Micro-Adjust-Guide.pdf

Based simply upon the first photo posted, you would need a MFA in the Minus direction.

Oh I was doing it at 19.8 feet. Used some online calculator for 200mm. I will give that a try this weekend. Rain here for next couple of days.

Thanks for the link and the help!