Polarizing Filters

Polarizing filters can be a godsend – they can really bring out blues in a sky, or minimize reflections in windows, and can really help to improve the quality of your work.  At the same time, polarizers can also be very tricky to use.  On my recent trip to Arizona (I shot a weekend with Rich Charpentier of The Airstream Chronicles), there were many opportunities to bring out the gorgeous blue sky, and contrast it with the amazing colors in the orange rocks that the American Southwest is known for.

The problem with polarizers is that the blue that is brought out is not a consistent blue – it usually gets stronger as you move toward the light source.  So, when you go to stitch things together, the results can be less than satisfactory with evident banding and shifts on hue of the blue skies.  Take a look at the example below to see what I am talking about regarding the banding…

See how the sky has blues that aren’t consistent?  It’s because I did not rotate the filter to accommodate the shift in blues as I shot across the scene.

Another problem is kind of hinted at above – what if you have a sky where you want the blue to pop, but the foreground includes a water reflection that is an integral part of your composition?  The answer here is to expose both with, and without the polarizing effect, and then blend together the two shots later in post production.  Masking off parts of images is much easier to deal with than the polarizing effect in the sky, but it’s a pitfall of panorama photography to be aware of.

As it happened, later on that day I was capturing another scene where there was no sky, so it was a non-issue.  Here, the key is to remember to spin your filter so that the reflection does reveal itself, otherwise you will think you are doing something severely wrong when you can see the reflection with your eye, but not through the lens.  I probably spent a good five minutes trying to change the angle of view before I realized it was just a quick spin of the filter to reveal the reflection below me…

As, as you can see, there are benefits to polarizers and there are also downsides to consider as well.  When used correctly, they can really add to the character of an image.  For those looking at specific recommendations, here are the ones in my gear bag:

• Moose’s Warm Circular Polarizer (58mm)
• Tiffen Circular Polarizer (77mm)

But enough about my thoughts on polarizing filters – what about you?  Do you think they are legitimate tools to alter a scene?  What about reproducing the effect in post production?  Which ones do you use?  Do you have a favorite or do you prefer all photography “au naturale”?  Sound off in the comments or via email!

Happy shooting and we’ll see you back here again tomorrow for more photography goodness!

Thanks to the folks over at Blubrry, I have been successfully able to implement a new alternative to embed podcasts into the native feed that already exists for CanonBlogger.  So, in the interests of getting the content posted to iTunes and to those feeds that had not been updated from web references, I am going to spend the next few days providing some video content updates.  The expanding ease of the .mov format not only in this interface, but also for portability purposes also seems to suggest that I am going to stick to that format exclusively for the foreseeable future.

For those that had been coming to the blog for their content, you will already have seen this video, but for those who have been waiting on the feed for new multimedia, this will be new material.  Today, I am re-publishing the tutorial on reducing noise in your images. Enjoy!  For the rest of you, see if you can tell the differences between some clouds shot with and without a circular polarizer.  Share your thoughts in the comments on which one is with and which is without.

Image A:

Image B: