Marumi 72mm Circular P-L, test samples.

OK, here is my review of the "Marumi 72mm Circular PL"

Out of the Box, the filter fits snugly in a square jewel case which doubles as a protective case for the filter. The CPL filter is coated black and about ~8mm thick and the glass is a grey tinted one. The front ring on the filter, as you rotate to adjust the polarization, offer some useful friction that feels good.

With the filter thread facing the laptop LCD screen there is some light blue-to-yellow color cast as you rotate the filter ring. but this doesn't seem to affect the image quality. I tested the filter on my DSC H50 (with 72mm lens adapter) for the reflections, blue sky and color saturation and was happy with the results. (see the image results below)
CPL filters are known to block some light and so does the Marumi 72mm CP-L.
Under indoor lighting I could see 1-2 stops of light reduction and about 2-3 stops under the Sun.

Reflection test
Both the images were taken indoor under artificial light and with the CPL on.
the first image show clear reflections around the subject that's with the CPL with minimum effect (as good as no CPL filter)
in the later image you see almost no reflections with the CPL set for maximum effect. see how the reflections have given way to the saturated color of background surface (actually a bed lamp table)

CPL minimum effect/without CPL - lot of reflections.



Almost no reflection with the CPL at maximum effect.

reflections and shadow exist where there is light, while the CPL doesn't have any effect on shadow, it reduces the reflections and glare that kind of acts as a sheet of haze, reducing the perception of color.
CPL filters reduce glare/reflections and brings out the natural color and therefore it appears saturated.

Blue sky test

Here are the test shots for the blue sky.

 without CPL filter                                                with CPL filter at maximum effect

Please note the effect is maximum only when your camera lens and Sun are at 90 degrees to each other.

It takes some practice to get used to the 90deg rule. once you figure out the technique you can play with how much blue you want to add and how much reflection or glare you want to remove.

I personally feel not to remove too much of the reflections as it will make your shot look too flat.

Hope this is of some help. Good day!

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