mixing polarizers

Hi folks.
Not sure exactly where to post this question, so mods please move it appropriately accrording to your understanding.

I soon will have new sunglasses ...and they will have a linear polarizer associated with the presciption.

But I also have a c-pol filter that I have been known to use not a small amount as well. Can I expect this to affect what I see through the viewfinder?

I.e. what is the expected effect of linear and circular polarizer stacked as I described? (My first inclination would be to say that it will depend on the phase of the c-pol...but I have no idea in which way.)

Thanks

You can expect the viewfinder to get very dark depending relative rotation of the two polarizers.

That has not been the case for me with a Marumi Super DHG CPL. The viewfinder is a little darker but no darker than everything else is when wearing sunglasses.

The LCD on the other hand goes almost black when shooting in portrait orientation. Just turn your head or camera 45 degrees for live view or to review images. But it can be a real pain in the neck when craning your neck for live view when the camera is above your head on a tall tripod. I carry a set of clear glasses in the camera bag for such occasions but more often I put the sunglasses in my pocket.

By the way I absolutely love prescription polarized glasses with the best coatings. It is highly recommended to go all out with the coatings. When I had bad or no coatings I always saw parts of my face or eye reflected off the back of the glasses. Very distracting and defeats the purpose of reducing glare. With good coatings I rarely see those reflections.

Hope this helps.

Polarized glasses should not cause the viewfinder to go dark when rotating a circular polarized filter mounted to the lens.

The quarter-wave plate that's added to a linear polarizer to make it become a circular polarizer essentially unpolarizes the light on the camera side of the circular polarizer. It does that so that autofocus and auto exposure systems in the camera can function properly.

If a linear polarizer is used along with polarized sunglasses, then you will see the whole scene darken through the viewfinder.

I have found that when i use a circular polariser, with my polarised sunglasses (Oakleys) that the left half of the frame looks ok, a little darker, and the right side goes very dark and yellow.

i take the sunnies off, or use my non-polarised ones when i am using a circular polariser