Polarizing filter?

To get the white balance right, do I have to take the white balance reading before I put the filter on the lens?

No, after.

Shoot RAW, easier to fix if WB problem anyway.

the WB reading should be the same as the sensor sees. So after.

x_tan wrote in post #13186262
Shoot RAW, easier to fix if WB problem anyway.

+1 for this...

a Polarizing filter has no effect, on the temperature/color of light. So you can make WB adjustments, either before or after you install the filter. Its only affect is to cut light by roughly 1/2 - 1 stop, depending on the amount of polarization used.

Because of the way the cameras today work, putting the polarizer on before you take your WB reading is the way to go. All the decisions made by the camera in regards to WB are done after the light reaches the camera itself, which means the light has to go through the lens and whatever filter you have on the camera at the time.

And, while shooting RAW will help if you fudge the WB setting a bit, if you set it first, that's one less thing you have to do after the fact!

steve40 wrote in post #13187015
a Polarizing filter has no effect, on the temperature/color of light. So you can make WB adjustments, either before or after you install the filter. Its only affect is to cut light by 1/2 - 1 stop, depending on the amount of polarization used.

For a good, high quality filter yes, but some filters may add a color cast.

Also, there is a different color of light overall that reaches the camera after the light has been polarized; think of trees on an Autumn day, where you reduce the glare from the waxy leaves, and there is much more color coming through to the sensor.

A polarizing filter has effect on the color of light, as far as the camera is concerned. Polarizing light only changes the angle of the light rays, to reduce reflections. Look at the color of the filter, its neutral gray that does not affect the way the camera sees light temprature. You can use a custom white balance if you feel that is important, or just use the AWB, it really makes no difference in most cases. There are a few circumstances where a custom white balance is necessary, but they are not the average.

It only took me a little over 60 years, to learn this little fact. The only filters that may affect light, are the sorry filters Tiffen makes they are always a little warm.

If you are shooting raw, set the body to AWB. In your PP software you can adjust temp (blue-yellow) and tint (green-magenta) in any direction you like.

MCAsan wrote in post #13187257
If you are shooting raw, set the body to AWB. In your PP software you can adjust temp (blue-yellow) and tint (green-magenta) in any direction you like.

+1

MCAsan wrote in post #13187257
If you are shooting raw, set the body to AWB. In your PP software you can adjust temp (blue-yellow) and tint (green-magenta) in any direction you like.

This. RAW allows you to not have to worry about WB while shooting.

Not everybody shoots RAW, or necessarily wants to. If you are so worried about WB, buy yourself a Gray Card. Set your white balance from it, after! you install whatever filter. Especially a Tiffen, they tend to be a little too warm.

steve40 wrote in post #13187085
A polarizing filter has effect on the color of light, as far as the camera is concerned. Polarizing light only changes the angle of the light rays, to reduce reflections. Look at the color of the filter, its neutral gray that does not affect the way the camera sees light temprature. You can use a custom white balance if you feel that is important, or just use the AWB, it really makes no difference in most cases. There are a few circumstances where a custom white balance is necessary, but they are not the average.

It only took me a little over 60 years, to learn this little fact. The only filters that may affect light, are the sorry filters Tiffen makes they are always a little warm.

I'm going to assume there should have been a "no" in that first sentence, and you're right in that a good polarizer will be color neutral. However, there is a difference in the color of light reaching the camera sensor. If used to, say, get a better exposure for the sky, much more blue light is going to be recorded, and the camera will adjust accordingly.