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cdub
May-11-2009, 02:43 PM
Hi everyone,

Just curious - when shooting outside under overcast conditions, do you (being you yourself or general convention) use a polarizing filter? I have used one under a couple of circumstances lately, mostly because I didn't think to take it off, but my images are obviously darker and I'm not seeing the benefit.

Just wanting to see what the wisdom of crowds has to say. I'll guess that I ought to take it off (afterall, aren't we talking about filtering out the sun's rays?).

Cheers

Tee Why
May-11-2009, 03:38 PM
Not sure of much benefit except decreasing the light coming in if it's overcast. I generally use it when it's very sunny and there are a lot of glare. I'm not sure with an overcast sky if the clouds would stand out more against the sky as it would on a sunny day.

black mamba
May-11-2009, 03:48 PM
I'm one who uses a polarizer quite a bit....due largely in part to the type of subjects I like to shoot. The primary uses of the filter are to reduce glare and to ( in a related fashion ) accentuate colors. Because the use of it will cause a loss of light in the 1 to 2 stop range, it can also be used to help darken an otherwise too bright scene. The circular polarizer needs to be rotated to determine it's most beneficial effect.

As to using the filter in an overcast sky situation, I would expect the benefits of doing so would be mitigated to a degree...but not negated alltogether. It would depend, obviously, on just how overcast the sky is. I have found the benefits to prevail even when there is moderate overcast.

Tom

schmoo
May-11-2009, 04:11 PM
Moving this to Technique for you! :thumb

HenryPeach
May-24-2009, 05:29 PM
It depends on the subject. The effects of reducing glare and increasing saturation are more subtle on an overcast day, but it still occurs. The difference between a sunny day and an overcast day is like the difference between a bare flash and a softbox; they are different, but there is still plenty of potential for saturation reducing glare. If I can I use the pol. It really helps foliage go from cool green to warm green, and helps cut a little of the overcast blue from most subjects.

Chris Geiger
May-26-2009, 08:20 AM
Normally I don't use a polarize filter on overcast days but here is a case where it helped define a reflection in the water.

http://chrisgeigerphoto.com/bbs/reflection.jpg

Don Kondra
May-26-2009, 08:41 AM
Which type of polarizer?

A circular polarizer will darken blue skies and reduce reflections on water, glass, etc. IF used at 90 degrees to the sun for maximum effect.

http://en.wikipedia.org/wiki/Photographic_filter

Cheers, Don

brocot
May-26-2009, 11:49 PM
I did not used the filter here, would I use it here ?
I have set the exposer - 1 to have more contrast.

http://erikgodderis.smugmug.com/photos/542933091_Qa5jz-L.jpg

jfriend
May-27-2009, 09:30 AM
I did not used the filter here, would I use it here ?
I have set the exposer - 1 to have more contrast.



Depending upon the angle of the sun and how your adjusted the circular polarizer, it could have eliminated a lot of the reflections off the water, allowing more exposure and more light from your backlit boat.

Mr. 2H2O
May-27-2009, 10:29 AM
Depending upon the angle of the sun and how your adjusted the circular polarizer, it could have eliminated a lot of the reflections off the water, allowing more exposure and more light from your backlit boat.

I agree and would expect it to deepen the shadow areas too if you didn't plan on exposure compensation for the backlighting - there's no free lunch. 1.5 extra stops on the shadow side of anything is pretty deep.

- Mike

HenryPeach
May-27-2009, 05:30 PM
Which type of polarizer? A circular polarizer will darken blue skies and reduce reflections on water, glass, etc...

A linear polarizer does the same. The difference is that a linear pol can mess with some AF and metering systems, and circ pol do not.