Landscape Filters

Hi guys,

Just wondering what filter kits anyone is using for ND Grads?

I'm using Cokin P series, because I can't afford Lee, rather than any technical reason. I only tend to carry a couple with me when out in the hills, ND2 and a Grey, I also have a Hoya circular Polarizers. However I don't use filters nearly enough or get the dramatic effect that some members of the site have.

Cokin Z-pro here because I got a good deal on them.

Besides that I use a polariser 90% of the time.

Don't shoot many landscapes though

I own Cokin P, but i would advise you not to invest in them as they leave a magenta cast when stacked.. so only useful for sunsets/rises really, and then still quite annoying

Theres a kit made by HiTech/Formatt that fit the Cokin P system, which I've heard great things about, and are a similar price.

http://www.formatt.co.uk/stills-filters/filters/graduated-n-d/stills-filters.asp...

I use Lee filters, currently I only have a 0.3, 0.6 and a 0.9 ND grads (hard edge). One good thing is they are large enough to be able to use them as normal ND's which the soft edge probably wouldn't. The softs are next on my list to order.

What actual effect could I expect from a circular polariser?

This may help sophie

http://www.dslrtips.com/workshops/How_to_use_polarizing_filters/reduce_haze_deep...

From the same site I always use, something about most if not all the photographic filters.

http://www.galitz.co.il/en/articles/filters.shtml

So the circularity is in the shape of the filter?
I read it as 'circular polariser', i.e. producing circularly polarised light. That can be achieved with quarter wave plates etc but it seemed not to fill the requirement of eliminating one particular plane of polarisation. The terminology seems to be a bit confusing. I have a rotating, circular shaped, polariser which, I guess is what 'they' mean nowadays.
Not being picky - just genuinely confused as I have a Physics background (not always an advantage).

From luminous-landscapes site:

Circular Vs. Linear Polarizers

There are two types of polarizing filters available — linear or circular. Linear polarizers are more effective and less expensive than circular ones. But circular polarizers are needed with just about any camera that has a through-the-lens metering system, or autofocus.

The reason for this is that both of these systems use semi-silvered mirrors to siphon off some of the light coming though the lens. If that light is linearly polarized it renders either the metering or the autofocus ineffective. This means that you're going to have to buy circular polarizers unless you're shooting with a pre-1970's camera, or a view camera.

Funny enough though the Camera don't seem to suffer from Linear filters, maybe something of the early days of AF?

Are you saying you've tried linear polarisers without any problem on your K10D?

No but members here have, don't ask for names though.

I thought the same thing when I came back to photography and first heard of CPs so I did an experiment. I put a CP on top of a linear and rotated one relative to the other. they behaved exactly as two linears would, so I dismissed that theory.

Here is some info link
I had found a better link once...

This might be it...
http://en.wikipedia.org/wiki/Circular_polarization
http://en.wikipedia.org/wiki/Linear_polarization