ThrillaMozilla

"This logic works okay for IQ but not so much for AF."

I don't know why it wouldn't. After all, focusing also works through the sensor. I think we'll have to wait and see.

Your point about M43...

OK, you're pointing out that color temperature refers to the light source but not the wavelength distribution of the subject. Fair enough. However, for what it's worth, color filters are intended ...

I missed the irony here.  A "warming filter" reduces the color temperature.  I would say it's misnamed. Photographic jargon is a bit of a mess.  If we're going to use metaphors, at least we ...

The "warming filter" in question is an 81A that is added to a polarizer to form the Moose polarizer. An 81A has a slight pink cast to warm pictures shot by skylight. An 80A is blue and much ...

Interesting.  This matches DPR's tests. Curiously, Bill Claff's data seem inconsistent with the pictures.

Guys, relax. The Sony A9ii is the comparable fast-action, low-MP camera. The 1D Xiii sensor is quite competitive with the A9ii. Better than the Sony at low ISO, within 1/3 stop at high...

Guys, relax. The DR is OK. Completely competitive with Nikon. Beats the socks off the D5 at low...

Well, I suppose that is one possible scenario: extinction of the sun's reflection on a glass window, or on water. I suppose it's possible under certain, rare conditions, to have a reflection with ...

Note that this is the Beginners Forum, and the OP seems like a very basic question. Hence the basic answer. But since no good deed goes unpunished, check out some extinction measurements: Polarizin ...

That is certainly possible.  It looks to me like the images are simply out of focus.

At the risk of restating the obvious, that only applies to the sky. And the mark is precise. If one understands polarization and knows what one is doing, one can rotate the mark to the plane of the ...

OK.

In the right orientation they do remove virtually all polarized light.  Photographic polarizing filters are almost perfect in that respect.  (Footnote:  someone once tested a horrible, cheap ...

I didn't measure with lab equipment, but my Hoya filter seems to be right on the mark. It's easy to measure, so I assume that generally the marks are quite accurate. I think it's possible that you ...

Possibly, but we're not talking about film. Here is the original question:

Oh, that really is not true. It's probably not what you meant. A color-balance filter is colored, so it will alter the color, and thus the color temperature, of everything that is photographed. ...

I figured that's what you meant, but that's not vignetting. Yes, that's a good illustration of the problem all right.

And don't use a polarizing filter. Check exposure on all images before you take the images, and make sure you don't overexpose any of them. It helps if the camera is level, although you can't do ...

No, I didn't quite say that.  In the sky, polarization is a maximum, 90 degrees to the sun.  In landscape orientation, you can get uniform polarization all the way from the left side of the image ...

I doubt that that's lens distortion.  You already know what causes this.  It's called parallax.  Next time keep the lens level so you capture more concrete instead of the beautiful sky.  But that ...