E.L.. Shapiro Loc: Ottawa, Ontario Canada

Don't drive yourself crazy.

I good CPL filter will not cause you exposure system to malfunction. If all the settings are correct for the program you are using there should not be underexposure. A CPL filter has some neutral density which means it absorbs some light but your metering system should automatically compensate for that. it should not disrupt you autofocus system either.

A good quality filter should not alter the color to any uncorrectable degree. You auto or manual white balance settings should no be disrupted.

A poor quality CPL filter will not "ruin your lens" it will just badly affect the images when it is in place. It will not damage the lens- just the results.

You can read up on the fine points of using your CPL filter as per angles to the light source but the nicest feature of this filter is that you will see exactly what it is doing as you rotate the filter.

Sand help emphasize the clouds on a clear bright day. You will see if it is working or not (as per your angle to the sun). When you change the angle by aiming the camer in various directions you will see the differences. It will not have any appreciable effect on an overcast day as far as darkening the sky.

In many different light conditions it can
increase color saturation on foliage and othere surfaces by eliminating certin reflection. Again, you will get to learn the ropes by experimentation- rotating the filter will yield various levels of the effect. It will sometimes eliminate some or all reflection on glass windows but you may prefer the leave all or some of the natural reflection as is because too much polarization will record the windows as black. The same goes for water- it you want to show some or all of the reflections in water you can if you overdo it the water may record a black or withou waves or current and look unnatural.

Maximum polarization is great for shooting through glass such as storefront windows, display cases, dioramas in museums and glass enclosures at the zoo or the aquarium. Again- just rotate the filter and determine effect and the necessary angel for best results.

I usually don't recommend CPL filter for portraits, I find it kills the kind of specular reflection that I want to retain.

jeep_daddy Loc: Prescott AZ

Yes, PH is correct about your image and it seems now you remember changing to Tv (Tv=shutter priority) Tv stands for Time Value which is the amount of time the shutter is open to expose the shot. You wouldn't have had this problem if you stayed in Av unless you accidentally had EC (exposure compensation) at -3 stops.

Now you see how useful the ticking of the box (store original) is. We got all that information and more by seeing the original photo.

Someone said that a CP filter had ruined their lens but not literally. I think what they meant is that it ruined the image because it was either a cheap CP filter or it wasn't used properly.

PHRubin Loc: Nashville TN USA

BTW - Welcome to UHH!

Bryan Petersons book "Understanding Exposure" is recommended by many. The exposure triangle (Shutter speed, aperture, ISO) is something to know about, how they interact and the side affects of each.

Pablo8 Loc: Nottingham UK.

Here we go with the old 'Chestnut' of mis- information. Polarizers do NOT have to be 90 degrees to the sun, to work. That mis-quote only applies to making a blue sky darker. When using a polarizing filter to control glare/reflections from a shiny surface, an angle of about 30 degrees to the shiny surface will be most effective. Does not matter about a 90egree angle for those purposes But too many people mis-quote that 'Rule', without adding clarification. Usually leads to confusing 'Newwbies'.

Shutterbug57

Sean Tucker has a 45 min video that explains the exposure triangle well. It shows the interrelation between each side and the effect of changing each side. Don’t be out off by the name of the video, the knowledge works in any camera mode.

https://youtu.be/LUtlZ3sahz8

Julian Loc: Sarasota, FL

Correct! Also, from another comment, maximum polarization is not achieved when the filter’s manufacturer name is on top or bottom of the lens; it all depends on the direction of the reflected (polarized) rays you are trying to cancel.

traderjohn Loc: New York City

For sure. I don't know how you can "ruin a lens" with a filter. Perhaps just take a bad picture.

A.J.R. Loc: Devon, UK

Please explain how a lens can be ruined by using an inferior CPL?

Gene51 Loc: Yonkers, NY, now in LSD (LowerSlowerDelaware)

Responding to your questions:

1. Polarizers do affect camera readings and, if shooting in an auto exposure mode, how the camera selects settings.

2. Yes, the whole idea of a circular polarizer is to easily adjust the amount of polarization. The most polarization occurs when the camera is pointed 90° from the sun. This is true early in the morning and during midday sun and for anytime the sun is out. If you point your camera at the horizon at 12 pm, when the sun is high in the sky, it will work just fine to remove specular reflections, such as sun reflections from foliage. A rule of thumb, literally, is to make a make believe pistol with your hand - index finger being the barrel. If you point your thumb at the sky, wherever your index finger is pointing would be where you would get maximum effect if you pointed your lens in that direction. if you go off the 90° it will still work, but you'd get less polarization.

The reason there are no specific set points on the filter is that the amount of polarization depends on sun and camera position. This is not "quantifiable" and cannot be calibrated. It is an observational thing - you look through the camera's viewfinder and adjust until you get what you want.

3. If you overexpose your image as you have in the example, while you can generally recover the image, you will have to do more aggressive noise reduction, sharpening and contrast enhancement in LIghtroom.

Here is an easy to follow guide on how to use a CPL for landscape:

https://photographylife.com/landscapes/how-to-use-a-polarizer

SuperflyTNT Loc: Manassas VA

That will only work if you’re using it to remove glare. For the sky you’re looking for that shade. Or the amount of contrast you want in clouds.

SuperflyTNT Loc: Manassas VA

I was about to suggest you spend the $20 and get this book, but I see PHRubin beat me to it so I second this suggestion.

bbrown5154 Loc: Baltimore, MD

Hi Megan. Polarizing filters work really well for eliminating glare and even some haze. The circular ones work best when the sun is at 90º but will also work when its at other angles, just not as well.
And yea its kind of a guessing game but you can usually see the results right away.
It will help to make the blue sky darker and really pull out the white clouds.
My view from the cheap seats is that it looks like there is something more going on with your exposure than with the filter. A polarizer usually drops 1 fstop but your entire image is way to underexposed to be the fault of your filter.
Double check your "bracketing" or "exposure compensation" and make sure your not set to (-).
Hope this helps.

mizzee Loc: Boston,Ma

I suspect that you may have accidentally activated exposure compensation into negative numbers.

dennis2146 Loc: Eastern Idaho

I think you have been steered wrong. Even with the cheapest worst circular polarizer on the planet you will not ruin the lens. You might get a bad photograph but the lens will be unscathed.

Dennis

camerapapi Loc: Miami, Fl.

First question is a yes, regardless of the shooting modality a circular polarizer will affect the exposure by as much as 2 stops at full polarization. Using a polarizer with evaluative metering is a no-no unless you look at the histogram after each shot. Center weighted works better.
The second question is also yes, polarizers do not have a setting to know how much polarization is been applied. When the filter makes the subject the darkest then you are at full polarization and you have lost 2 stops of light which means that to compensate the exposure you have to add 2 stops of light. I hope you know the basics.
For question No. 3 the closer you are to the correct exposure the better your images will look in post. Your images are underexposed because of the polarizer and your technique when shooting with the filter. Use center weighted metering, meter from a middle tonality and use plus 2 stops of exposure compensation for the correct exposure.
I use the polarizer most often to eliminate reflections from non metallic surfaces, not to darken the sky. I do not use the polarizer to shoot people. Always use the polarizer in landscape photography at a 90 degree angle to the sun and if the sky is important never shoot a landscape with a polarizer combined with a wide angle because part of the sky will not be polarized.
Hope this helps.