Perhaps a silly question about exposure with a Polarizing filter

Captured Exposure

Hi,

I was rotating my polariser at a white background on my monitor and it goes from very light to very dark...does this mean the amount of light getting through would be changing and in turn the number of stops would change as your are rotating it?

Hope that makes sense.:scratch

Snowgirl

Captured Exposure wrote:

Hi,

I was rotating my polariser at a white background on my monitor and it goes from very light to very dark...does this mean the amount of light getting through would be changing and in turn the number of stops would change as your are rotating it?

Hope that makes sense.

Exactly. As you rotate the polarizer it increases / decreases the polarizing effect - most noticeable if the sun is at 90 degrees to the camera - i.e. off your shoulder. The more you increase the polarizing effect, the less light is getting through and so yes, depending on what you're after, you may need to ope your aperture some.

pathfinder

Sounds like the light from your monitor is polarized, and hence, filtered by your polarizing filter.

If you shoot in Av, the camera will vary the shutter speed as needed to compensate.

If you shoot manual, you will have to adjust the shutter speed, or the aperture, or the ISO, to compensate.

Captured Exposure

Great, thanks.

Dan