Using a Circular polarizer on an E-M5 III

[GBarrington]

I haven't used anything but a linear polarizer on film SLR cameras. With an E-M5 III, should you be able to see much change in the viewfinder when you rotate the filter? In some scenes, I see a very tiny amount of difference when the filter rotates, but on most, I see no change at all. I got the camera just yesterday and aside from date and time, it is at the default camera settings. And I'm using it on a 12-40 f/2.8. Everything on full auto. I should add these are snow scenes since that is all that is available where I live right now.

This is a Zomei filter that was given to me. And I promised to show him some photos it takes. It clearly changes when I hold it up to my eye and rotate, and I found a video on YouTube that claims to tell you how to spot a good CP, and it seemed to pass. The only thing I can think of is either camera settings, or, CP filters just don't work that well on mirrorless.

Can anyone give some guidance? How do you use these things?

 

[PakkyT]

It should work equally as well on mirrorless as any other camera. It may simply be the difference between looking through the filter purely optically with just your eye and how it looks on the EVF (is that one OLED?) or the back LCD. I have found the effect does seems a bit harder to detect when looking at those screens.

Does your filter have a mark on it (typically a line or maybe a triangle symbol) on the ring somewhere? A lot of times if you are having trouble seeing the effect on the screen, this indicator on the filter marks where the sun should be for maximum effect. So you basically turn the filter so the mark it towards the sun. Otherwise I will often look for the most reflective thing in my shot (water or even the glossiness of leaves on bushes) to see when the "gloss" goes to the minimum, when looking at the sky or something like that isn't as indicative.

 

[alan1972]

I find that with everything on full auto as you say, it can be hard to see the effect of the filter as the exposure tends to change to compensate for the impact of the filter (eg if the filter darkens the sky the auto exposure brings it back up again).

You could try using Manual mode (without auto ISO) or auto exposure lock to keep the exposure fixed while you rotate the filter. Once you are happy it is in the correct position you can go back to auto exposure.

 

[roelwillems]

Very good tips on switching off auto (exposure and ISO) to keep the camera not trying to "correct" for the polarized image.

Maybe already common knowledge as you used polarizers before, but the angle of the light also has major influence in how strong the polarization effect is.

Polarizers have the strongest effect being 90 degrees to the sun, shooting at 45 degrees will roughly mean that the polarization effect is reduced 50% shooting straight in to the light and you end up with no polarization effect at all.

Simple but useful technique is to make a 'L shape' with your thumb and index finger. Now point your index finger at the sun, your thumb will point in the direction where the polarization will be strongest (if you point the lens in that direction as well, you will get maximal polarization).

Still, with good technique, I do find that an EVF isn't very well suited to show the final polarization effect. So you maybe see max 70% of the final effect it has on the image you shoot.

 

[Hendrik]

Turn off Live View Boost and S-OVF. They will both confound the EVF and mask the effect. Once the viewfinder is WYSIWYG, you will see the changes properly rendered.

 

[GBarrington]

Thanks Guys! These suggestions seem entirely reasonable! I'm going to try them out tomorrow!