Polarising filter usage

[meddyliol]

I expect that this has been done to death but I just cannot quite get to grips with some aspects. I can understand that the best place to use it is when the sun is directly to my left or right (I think). What about if the sun is directly overhead? Will the filter be effective in any direction? Are there any good diagrams anywhere which explain it better? Sorry for being a bit dense but I haven't received the filter yet so am trying to get as much info as possible.

Thanks

Brian (as usual)

[purplehaze]

Hi Brian, I believe you want the sun at 90 degrees from the lens, so when the sun is directly overhead, that is ideal, so long as your lens is lying perpendicular to the line between you and the sun.

[Shadowman]

This link should help.

https://www.cambridgeincolour.com/tu...ng-filters.htm

[PhotomanJohn]

I would suggest that you also take the filter outside and simply look through it in different situations and directions while rotating it. You don't need to bring your camera. They are simple devices with no magic involved. A little experimentation will help you figure them out.

John

[Geoff F]

From my experience, Brian, the best place for a polarizer is in the camera bag.

With film cameras they were useful for changing the scene between yellowish and blue tint which could be handy for creating better skies etc. But all that can now be done with better control with white balance adjustment during processing.

If you only shoot in auto settings, without any exposure compensation, then yes a polarizer will darken your scene. But I never use them because I always use aperture priority (or shutter priority) and tweak each shot to get the best lighting with exposure compensation after metering the scene.

A circular polarizer can be adjusted to suit the actual sun angle for any shot.

[Inkanyezi]

If its best place is in the bag, then there must certainly be a time to use it.

Polarisers, no matter whether circular or linear, do the same thing. The "circular" denomination is because such a filter depolarises the light after passing it, so that semi-transparent mirrors before AF sensors and the light meter may receive unpolarised light. Mirror-free shooters need not worry, linear polarisers will work exactly the same as circular ones.

As suggested, at an angle from the sun, the sky may become more saturated than without the filter, as polarised light from all haze in the atmosphere is subdued. Also, the filter may take away reflections from foliage or a water surface, effectively killing the image by removing what gives it life. Instead of a myriad of reflections that indicate indivudual leaves or ripples on the water, one can have a dull green mass or water that is transparent, so that the bottom can be seen and fish.

Whether or not to use it is a matter of judgement.

I have polarisers in my camera bag. They don't take up a lot of space, so I'll let them stay there - err... I mostly let them stay there. When I want to take something in a shop display window, I sometimes screw a polariser on and shoot at an oblique angle toward the window.

[Tringa]

The guide on here is good but also as John suggests just have a play with it outside. The darkening effect on the sky, as already mentioned, is greatest at 90 degreees away from the sun.

However, sometimes the effect can be a bit OTT but as you can rotate the polariser you can alter the effect, and, as noted in the tutorial, the with wide angle lenses the sky can look odd due to the effect being greatest in a particular direction.

The reduction of reflections from non metallic surfaces is also very handy effect of the filter.

It is at times very useful piece of equipment.

Dave

[rpcrowe]

I disagree with Geoff. There are many things that a polarizer will do that you cannot do in Photoshop or other editing programs...

Granted the sun is best in the proper position but, the polarizer can continue to be useful with the sun at a variety of angles - it doesn't quit being useful when the sun is at 89 or 91 degrees rather than perpendicular to the lens. It's just that the maximum polarization happens at that angle.

Reducing/eliminating reflections is one just one thing that the polarizer can accomplish but, the elimination or reduction of reflections can do much for your images:

See into windows past reflections on the surface
See below the water surface and eliminate glare from surface of the water
Saturate foliage by eliminating reflections on wet leaves
Penetrate mist or fog a bit by reducing reflections from the particulates

It will darken the sky and enhance the clouds. In doing so, it will reduce the exposure variance between sky and ground to a point where it may be captured better by the camera. IMO, it looks better than using a GND filter to even out the exposure between sky and ground

It will reduce your exposure by a couple of stops and often allow a slower shutter speed or larger f/stops

I certainly don' use my CPL for all shots but, it's with me when I need it.

Combining a CPL with a linear polarizer becomes a makeshift variable neutral density filter

There are a few problems associated with using a polarizer:

Shooting through airplane windows can cause a moire effect
Using a polarizing filter with a UWA lens can cause uneven exposure
Using a polarizing filter can cause problems when shooting for panos

And of course, an "EL-CHEAPO" brand filter may cause havoc with your image in many ways including sharpness...

[Mike Buckley]

Saturate foliage by eliminating reflections on wet leaves

Also on dry leaves.

[Manfred M]

I too will have to strongly disagree with Geoff. I use a polarizer a lot when doing outdoor photography. While many people primarily associate using a polarizer with a darker, more saturated sky, I use it to remove glare from leaves and grass all the time. This means a crisper looking image, regardless of whether or not I have any sky in the image.

I will also use it when shooting ponds, rivers and lakes, images through glass, i.e. Any time I am trying to control reflections.

[Mike Buckley]

Another use of the polarizer is to reduce or eliminate glare on the faces of people in informal situations. While that can be controlled during post-processing, it's a lot easier to control it at the time of capture.

[Ken MT]

Here is an example of with and without polarizer on water and seaweed.





I usually carry a polarizer, but don't always remember to use it.

[meddyliol]

Wow, I wasn't expecting such an in depth set of replies. Of course, the best thing to do is just experiment, if I don't do that I will never learn how to use it (or anything else for that matter). I like the pics by Ken MT

Thanks a lot everyone, you have, between you, answered my question and more.

Regards

Brian

P.S.
Unrelated but is there anywhere to list equipment? i.e. A signature area?

[Tringa]

Brian, if after logging in, you go to 'Forum Action' and then choose 'Edit Profile'. On the left side there is the option to 'Edit Signature'.

Just add what you want there. I think there may be a limit to how much you can add but you'll get a few lines worth.

Dave

[meddyliol]

Thanks very much Dave.

[Mike Buckley]

I seem to remember that the signature area explained by Dave doesn't become available until you have posted 10 messages.

[meddyliol]

That probably explains why I cannot find it. Better get some more posting in.