I just got my lenses in - B+W stuff, very nice quality, however, i'm curious...currently for the hell of it, I put the polarizer on first then the UV lens then the WA lens.

I remember reading that putting a UV lens sandwiched between a polarizer and WA lens is pretty much useless....

why is this?


so is it a NO-NO to have the polarizer then the UV then the WA lens? is it bad at all?

thanks!

It just produces more glare and takes more light. In a way any glass filter is a UV filter, so you don't need a dedicated UV filter when you have other filters on.

Hrm, I thought that the polarizer was good for just doing that....and was NOT good for being a UV filter or Haze type filter.

How does a UV in front of a polarizer create more glare and take more light?

more glass surfaces=more light absorbed as it passes through, and more planes to reflect glare as light bounces off

Hrm, I thought that the polarizer was good for just doing that....and was NOT good for being a UV filter
Glass absorbs UV light. This is why you don't get sunburn when you drive a car on a sunny day with windows up. Specially produced glass called quartz passes UV through.

dont forget the risk of vignetting of the 2nd element away from the camera lens. you can always zoom in to eliminate the vignetting but then you lose the wide angle ;)

Hrm....

wait so its not sounding like this is a bad thing.

or am I completely misunderstanding all of this.


having a UV in front of a polarzier (by the way its the B+W Kaesemann polarizer)

isn't really that bad of a thing.

Why would you need a UV filter? Besides a slight (max 1 stop) transmission loss through the lens, the sensor itself is, unlike film material not sensitive to the UV spectrum. A polarizer will do the job and is at least as good as a UV filter for reducing haze when rotated in the optimal angle.

Okay, I understand now.