polarizing filter

[Corran]

I might have missed it but I don't think anyone has mentioned yet that the effect can greatly change depending on time of day, season, elevation, etc.

I use a polarizer all the time. Here in the south, in the summer, with a polarizer AND a red filter, I might get some okay middle-gray to light gray skies with open shadows (as opposed to blown-out skies or blocked-up shadow values). The polarizer doesn't do much in that season generally. In the winter the polarizer is much more effective. And when I travel north and go up to the Smokies, the polarizer is way, way more effective.

There's only been one time that I overdid it - I blocked up the shadows by using a polarizer in the winter and a 2-stop GND filter on the sky on a Velvia chrome, which made the sky totally black.

[JMO]

Can someone please make clear which type of polarizing filters are being discussed here - are the responses assuming circular polarizing filters, or linear polarizing filters? And since there are responses in this thread concerning use of "polarizers" with B&W film, and color film, would there be a difference in the type of polarizing filter that a LF photographer might (or should) use with B&W versus color film? Thank you for these clarifications....

[Greg Miller]

Can someone please make clear which type of polarizing filters are being discussed here - are the responses assuming circular polarizing filters, or linear polarizing filters?

It doesn't matter for LF. You will get the same results with either.

It only matters if you are using an in camera exposure meter or or auto-focus, which requires a circular polarizer.

So LF can use linear or circular. DLRs will need circular.

[Heroique]

I'm curious about what filters you are using.

I use a Marumi polarizer, not too expensive, which does great work, and is close to color neutral, but never fully so.

My ND filters are un-coated Nikons, which are less "neutral" than the Marumi polarizer – but strict color neutrality usually isn't a key objective for my landscape work, so it's not a big issue.

My Lee 6x4 GNDs are all around fantastic performers.

Now, my 10-stop B+W ND filter is a different story. It's not neutral at all. In sunny scenes, it causes a 970K drop in color temperature (more red). I often use a Lee 80d filter to help correct its "non-neutrality."

Here's a fun thread about the B+W 10-stop ND filter and suggested color corrections:

http://www.largeformatphotography.in...top-ND-filter)

[Greg Miller]

I just checked a bunch of digital files shot with a B&W 10 stop ND filter and I see no color issues.

[Heroique]

I just checked a bunch of digital files shot with a B&W 10 stop ND filter and I see no color issues.

Are your reading glasses tinted blue?

Since you're talking digital, you might try a search about 10-stop ND color casts at, say, dpreview.com – the experiences reported there from the "dark side" will surprise you! Just be careful to separate the wheat from the chaff – there are more self-proclaimed experts there than here.

Me, I'm just a film person whose personal field notes determine his way...

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Just for fun, here's a polarized-induced, melodramatic sky on Velvia 100F to help illustrate a few remarks by people above.



The sky might have gone indigo had the sun been lower to one side.

This is the scene as my emotions recall it, not as my critical eye observed it.

Tachi 4x5
Schneider XL 110mm/5.6 (w/ Marumi polarizer)
Velvia 100F Quickload
Epson 4990/Epson Scan

[Greg Miller]

Are your reading glasses tinted blue?

Since you're talking digital, you might try a search about 10-stop ND color casts at dpreview.com – the experiences reported there from the "dark side" will surprise you! Just be careful to separate the wheat from the chaff – there are more self-proclaimed experts there than here.

Me, I'm just film person whose personal field notes determine his way...

I take a reference photo without the 10 stop ND before I make the shot with the ND. There is no color balance change between the two photos. And i use a constant WB. So it doesn't really matter to me what anyone else wants to say, because I can see for myself that the filter, at least my copy, does not cause a color balance issue.

[Doremus Scudder]

I shoot B&W almost exclusively. I use polarizer often. If you want to remove reflections from rocks, water and foliage (which is not always a good idea), it can work well. I end up using it a lot at the coast, usually only partially polarized, to take some of the glare, but not all, off of things.

Using a polarizer to darken blue skies can be helpful, especially since this won't affect the shadow values as a colored filter would. Be aware that polarization of the sky is strongest at approximately 40° from the sun. If you use short focal-length lenses and have lots of sky, you can end up with a lot of variation in the amount of polarization.

Many avoid this like the plague. I use it creatively on occasion, to darken sky on one side of an image while keeping it much lighter on the other.



Yin-Yang Hills, Death Valley, CA. 1999

Best,

Doremus

[Kevin J. Kolosky]

do larger diameter polarizing filters work well on smaller diameter lenses, or must they be the same size.

[Greg Miller]

do larger diameter polarizing filters work well on smaller diameter lenses, or must they be the same size.

That would be no problem. Many people purchase a polarizing filter at the size of their largest lens. Then use step down adapters to use the same filter on smaller lenses.