Linear vs. Cirular PL on manual focus lens

Linear polarizers can be a problem for autofocus cameras with autofocus lenses, but how about manual focus lenses (e.g., Zeiss 35mm f/2 ZE) on autofocus bodies? Would such a filter compromise focus lock signaling from the lens to the camera?

I don't have any experience but I think it is. Because, the af confirmation light on manual focus lenses works the same with the autofocus one, but without the af motor, which became our hand. It is only my speculation though, and i bet contrast detect af in live view can still be done. Feel free to correct me.

if you've already got one, just try it out.

i believe linear polarizers can be a problem for some camera's autofocus and metering systems. i've read where people have used them on modern dslr's with no adverse effects. i remember reading a theory where it'd be a problem if you didn't have cross-type AF points. i don't know what the final outcome of the tests were. if you could manually focus and had your camera in full manual, i don't think it'd be a problem. i have a feeling you'd also get your focus confirmation.

The reason that linear polarizers present problems with AF cameras is that the light getting to the AF sensors has to pass through a partially-reflective mirror to reach the sensors. In some orientations, the LP will block all of the light that would otherwise reach the sensor. If you are not relying on those sensors providing any feedback, you could use a linear, but you can't rely on the focus confirmation, which signal comes from the camera body, any more with a MF lens than with an AF lens.

Jon wrote in post #10311737
If you are not relying on those sensors providing any feedback, you could use a linear, but you can't rely on the focus confirmation, which signal comes from the camera body, any more with a MF lens than with an AF lens.

So it sounds like a CPL is the route to go. Thanks Jon.