What’s Your Preference?

AlphaBjerke · #1 (**permalink**) 03-08-2009, 07:11 AM

I am confused. I have read in numerous places that one must turn the polarizing filter until you get the look you want. When I turned mine, I could see no difference whatsoever. It turns and it obviously turns for a reason, but I don't see "the sky turn blue" as one forum said, when I turn it. What am I doing wrong. (To think that i am so inept that I can't turn a filter to make it work!)

Thanks!

P.S. And why would turning it make any difference anyway? It is the same shade the on th e whole area of the filter?

Arun · #2 (**permalink**) 03-08-2009, 07:38 AM

Hi,

The sun needs to be at 90 degrees to you to get the greatest impact. Have a read of this link. It explains it all.

http://digital-photography-school.co...rizing-filters

Cheers

AlphaBjerke · #3 (**permalink**) 03-08-2009, 07:50 AM

Thank you. I will have to try it again, though, because i swear nothing changed when I turned it. I read the article and a couple of others, so thanks for pointing me in that direction.

RoyL · #4 (**permalink**) 03-08-2009, 07:59 AM

It can depend on whether it is a cheap unit or not. Some of the el cheapo's just can't hack the pace.

When you use it make sure you look through the viewfinder as the changes may be subtle, those screens that people like to use today are useless at best.

And turn the polarizer slowly. Your eye's are not as fast as the lens

navcom · #5 (**permalink**) 03-09-2009, 03:05 AM

I agree with RoyL...cheap polarizers sometimes don't do much. And being 90 degrees to the sun is very important.

But I'm leaning to one other idea...are you sure your polarizer is a circular polarizer or is it a linear polarizer? Might want to verify that. A linear polarizer may still have rotational functionality but will have a different effect than you are looking for.

pdmedic · #6 (**permalink**) 03-09-2009, 05:27 AM

Quote:

Originally Posted by AlphaBjerke

P.S. And why would turning it make any difference anyway? It is the same shade the on th e whole area of the filter?

It it's one shade throughout you won't notice a difference I think the turning it comes from using a split polarizing filter.

navcom · #7 (**permalink**) 03-09-2009, 01:22 PM

Quote:

Originally Posted by pdmedic

It it's one shade throughout you won't notice a difference I think the turning it comes from using a split polarizing filter.

You are thinking of a graduated neutral density filter. There are two types of ND filters. Grad ND filters have one half clear and one half shaded. Standard ND filters are shaded the same over the whole filter. Standard ND filters and polarizers look very similar but do completely different duties.

A circular polarizer is designed to filter polarized light. Think of them as sunglasses for your camera lens. It reduces reflections from glass surfaces as well as water. It doesn't make them disappear exactly, but just filters out the light wavelengths that generally cause glare. It can also enhance colors by making them appear more saturated. A traditional circular polarizer can really enhance blue skies or blue water. There are other ones, referred to as blue-and-gold polarizers, that can enhance blues as well as give off goldish colors depending on the angle the polarizer is rotated in relation to the sun.

Polarizers are designed similar to window blinds. They filter the light in one direction while allowing it through in another direction. You rotate them to get the perfect angle to the sun which will give you the desired effect. That is why it is important to be about 90 degrees to the sun when using one. As you depart from 90 degrees, the filter becomes less effective, so-to-speak.

A neutral density filter works differently. It filters all light in all directions. It doesn't reduce glare...just reduces the intensity of light allowing the photographer to have slower exposures. The best example of why you would want to use a ND filter is trying to get that waterfall to look silky during the middle of the day.

During the day, the sun is so bright it will usually require very fast shutter speeds to get proper exposure. This means you capture all action instantaneously...no motion blur. But with a waterfall, you may WANT motion blur. So putting on an ND filter is basically making it appear darker outside to your camera, in which case it will need a slower shutter speed to get proper exposure...and thus more motion blur which gives you that silky effect.

ND filters come in different light-blocking levels, from very slight to almost pitch black.

Hope that helps!