[richardstringer]

Does anyone have a Marumi circular polarising filter? I've got one and supposedly the little arrow is to be turned in the direction of the sun, but when I do, I get nice polarisation in the middle portion of the sky but at the sides it fades oout to being normal. My old Hoy was better, I never this problem. Does anyone know what's going wrong?

[vanyagor]

My guess is you were using the filter on a wide lens. then it is an unavoidable effect

[richardstringer]

Yeah I had the focal length set to 18mm, what kind of focal length should I use to get the best effect? By the way, here's some test photos I took, some with the little arrow on the filter on top and some with it pointing towards the sun. I really don't like the effect of the polarisier when used properly, it has a kind of desaturating smoky colour effect.


1. Sun - 90 Degrees, Arrow - Top





2. Sun - 90 Degrees, Arrow - Facing Sun





3. Sun - Behind, Arrow - Top




4. Sun Behind, Arrow - Facing Sun




5. Sun - 70 Degrees, Arrow - Top




6. Sun - 70 Degrees, Arrow - Facing Sun



As you can see, the filter when used at a 90 degree angle how the filter is supposed to be used gives maximum effect but has a smoky colour and kind of desaturating effect, I much prefer my old Hoya, it DID saturate colours more and didn't have a colour effect. What do you guys think?

[bdery]

There is no perfect focal length for using a polarizer, but the wider the FL, the more you will see a gradient on the sky. In general, my personal experience suggests that I am not comfortable using a polarizer wider than about 30mm. The reason is based on physics : the angle between the Sun and the particles diffracting the light towards you changes a lot in your frame, leading to different effects across the field.

[richardstringer]

No I meant what's the minimum focal length you'd use when using a polariser, but ok 30mm, thanks.

[Na Horuk]

The sky does not have uniform polarization, so if you get a lot of the sky in the frame, there is a bigger chance that some parts will be darker than others. That is why the wider the lens, the bigger the chances of that happening. Sometimes, you can use a very wide lens and have no problem at all, other times it will be very noticeable even with 24mm. You kind of have to do it based on the light situation in front of you.
But a polarizer is a great tool to improve landscape and nature photos you get out of your kit lens, because it lowers the contrast on the sky or reflections from plants and water. And usually it doesnt bother viewers if a part of the sky is a little darker. Not to mention, if you shoot raw, you can make it less noticeable in post production
Also, even without a polarizer, with a wide angle lens, the sky will be much brighter near the sun, so the sky is almost never perfectly uniform.

[Wingincamera]

I have the Marumi circular polarising filter and use it with my 35, 50 and 70 primes, which are 49mm thread. I really like the filter, no problems like you describe. I do have the 18-135 lens which I use a 62mm Hoya polariser, but I don't think I ever used it in the 18-30 range. I plane on replacing the Hoya with another Marumi.

I also purchased a Marumi neutral density filter which appears to slightly reduce sharpness. I noticed on their web site that they have all new neutral density filters under a different name. I might try another one.

[richardstringer]

I've got the Marumi on ebay and have bought myself a Hoya instead and the Hoya is way better.