Good beginning polarizer to buy?

[jesse_whittle_utter]

Hello,

 

I shoot with a Nikon D200 and use two Tamron lenses: a a 28mm-75mm (or

thereabouts) and a 75mm-300mm zoom. Other than occasionally screwing on a UV

filter for protection, I don't modify the in-camera optics much. I hear a lot

of talk about polarizers - circular polarizers, in particular - but must admit I

have yet to come across a simple definition of what they do, why they're needed,

what focal lengths they work best for, and what type of photography would

benefit most from their use (I'm mostly active in nature/street photography, so

I work in a variety of lighting conditions, mostly natural.) I use Adobe

Photoshop CS3, so any effects I can achieve in post-production would not be

priorities for a polarizer.

 

Can anyone recommend a good piece of equipment that could match my camera,

lenses and interests? Or, if that question is impossibly broad, could someone

point me toward a reliable resource I could use to research this further? Thanks!

 

Jesse

[bobar57]

I believe that a good circular polarizer filter will be a Hoya multicoated, they're good quality and not so expensive as others.Make clear that you need a CIRCULAR polarizer, not a regular polarizer, the circular are the ones that work with auto focus lenses.They're used mainly to cut the glare from objects and intensify the blue of the sky, making a good contrast with the clouds.You can use these filters in both of your lenses.

[bobar57]

I forgot, they cut also the glare of the water.

[ronald_moravec1]

A secret is I use three Tiffin Linears for $40 and they work fine for exposure and autofocus on my D200. The store owner asked me to keep it quiet.

 

They vignette a little and make the shot a little green. Closing the lens one stop fixes the dark corners, and a small raw adjustment fixed the green. It is a preset I programed into ACR4.2.

 

Some cams do need circulars, but the D200 is not one. My Leica R cams need one for full function.

 

These are like automobiles. You can spend as much as you want. The final pic does not know it was a circ or linerar.

[michael_dimarzio]

Ronald, why would you recommend a polarizer that shifts color and vignettes? I guess that would work on a 20 dollar lens?

 

On the subject, there is more free information on this and every store that sells them, try a google search for the basics to the advanced. There are a few variations to this filter, the information is easy to find.

[bmm]

Just so you know, Hoya sell and "Introductory Kit" comprising 3 filters - a UV, a circular polarising, and a warming - along with a pretty handy filter satchel that protects them well. They come in most common lens sizes.

 

I got a couple of these with my order of camera/lenses/etc and have been really happy with them as a new photographer. I'm sure I'll move to better filters later but they are a good place to start and good value for money. Just look on the major online stores and I'm sure you'll find them.

[craig_gillette]

It's probably easier for you to look up the technical details of how they work and why some cameras can or can't use linear polarizers. When it comes to choosing them for photo use, there are a couple of considerations. Circulars are more expensive but they can be used on any camera whereas linears may be limited.

 

Coatings: As with other filters, the quality of "coatings" can be important. The filter deals with reflected light from the subject, the lens coatings deal with light being spread or reflected by the filter. You want light to pass through the filter to the lens with as little disruption as possible, not withstanding the desired effects of the filter. Poorly or uncoated filters can diffuse the light, or reflect some of it back or away. They can also cause light that is scattered or reflected within the lens or off the "sensor" to to be reflected back into the lens - this reduces contrast, adds scattered light to the image or shows reflections from bright spots, lights, etc. It's like looking at a picture under cheap, plain glass, you are hampered by reflections from the glass and can't see the picture well.

 

The quality and type of coating improves this kind of performance. And the best coatings are both good at doing their primary job of dealing with light and are harder (resist damage) and easier to clean as well.

 

A polarizing filter is a lamination. The Kasemann (IIRC) type filters are made in a way that seals the filter edges. This makes for a potentially more rugged filter as foreign substances can't get between the layers - water seems to be the big culprit.

 

So, cost goes up as the size of the filter goes up, quality of the glass used, then quality of the coatings, the rings, the thickness or thinness, and if a Kasemann lamination.

 

Polarizers are used heavily in landscapes, for water reflections, controlling bright white clouds, fall colors (shiny leaves reflect a lot of light around). The effects aren't duplicatable in post processing. There are some problems with very wide angles. The polarization effects vary somewhat with the angle of the light from the sun, some directions being darker. With really wide angles, the picture takes in a broader section of "sky" so it's harder to not have portiuons of the sky go from lighter to darker - when the natural look would be even as you look at it. The other problem is that because they are thicker to have layers and to allow for attachment and rotation, there can be vignetting with really wide lenses.

 

Many of the lens makers/sellers' sites go into more detail. Here's a non-seller's perspective:

 

http://www.luminous-landscape.com/tutorials/polarizers.shtml

[lex_jenkins]

Don't buy an expensive used polarizer sight-unseen unless comes with a guarantee. Polarizers can oxidize with age, which is what the Kasemann types Craig mentioned are designed to protect against. And why they're much more expensive.

 

Hoya and Kenko polarizers (and their other filters) seem to be good values. They don't seem to oxidize as readily as other lower priced polarizers.

 

If you get hooked on polarizers you might later want to move up to a more expensive B+W or other premium brand.

 

BTW, another cost effective way to experiment with filters if you want to try a variety on various lenses having different filter size requirements, the Cokins are a decent value. They aren't the best quality filters and most tend to scratch and scuff easily (they're made of "optical resin" - aka, plastic). But a set of basic Cokin filters, a holder and a variety of adapters for various filter thread sizes can be useful for experimenting and deciding which filters you like best and which sizes are worth investing in when buying better quality.

[les_barstow]

<p>If you can, try before you buy. Some lenses are picky about filters; my Nikon 80-400VR reacted quite poorly to an inexpensive circular polarizer (it wouldn't quite focus correctly - had a similar but less severe problem with a UV filter) and I wound up purchasing a much better filter to replace it.</p>

<p>A polarizer is now the only filter I carry in my bag. It's the only filter that can't be duplicated digitally, and it's a vital component for landscape photography.</p>

<p>Technically, light is often (partially) polarized when it is reflected, transmitted, or refracted - the light waves oscillate in one orientation. A polarizer filters out light oriented in a specific direction. Turn the polarizer perpendicular to the incoming light's orientation, and that light is blocked; adjust away from perpendicular, and more and more of the polarized light is let through. This has several beneficial effects:

<ul>

<li>In nature, light is "scattered" rather than evenly reflected; this means you won't usually block all the light, but you can more easily block the most uniformly reflected light - glare. Glare reduction is usually strongest when you are at around a 30-degree angle to the surface.</li>

<li>In diffuse light (with uniform random orientation), a polarizer will block half of the light - a 1-stop reduction in speed. Thus a polarizer makes a cheap 1-stop ND filter - with glare reduction.</li>

<li>Refracted light is polarized just like reflected light. This means you can strengthen the appearance of a rainbow with a polarizer.</li>

<li>Sky lighting is also polarized - much more with direct sunlight than on cloudy days, but the effect is always present. 90 degrees away from the Sun is the strongest effect. This can reduce haze, increase perceived visibility and color rendition, and darken skies. Wide-angle lenses can yield variable sky color with a polarizer, and high-altitude skies can be rendered black with a polarizer because of the uniformity of the light.</li>

</ul></p>

[mike_langieri]

OK, here's a related question Les. If you were using a 18-200 VR would you not keep a "protective" filter on it, and if you would... what would be your choice aside from the obvious circular polarizer. Also, just curious if anyone has any issues with vignetting with a 18-200 VR and a circular polarizer.

 

Craig, great info and link!

[les_barstow]

I no longer keep a protective filter on my lenses; I always put a lens cap on when I'm not shooting, so it doesn't make much sense. I did formerly use a UV filter as a protective filter, but it's just one more piece of glass getting in the way of a good picture... If I were in a sandstorm and needed to get a shot, I'd dig it back out, I suppose. I'd recommend a multi-coated UV filter as a protective filter over other options.

 

Thom Hogan's review of the 18-200VR seems to indicate that vignetting shouldn't be a problem with even a full-sized circular polarizer - the image circle is actually much larger than the DX format requires. I would test before using a 72mm polarizer at 18mm wide-open - which shouldn't happen frequently in real life. If you have some pro-sized lenses along with your 18-200, I'd buy a step-up ring and use a 77mm filter instead.