A guide to using polarising filters

[DPNow]

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A polarising filter is a very handy tool to have in your camera bag when you have nice blue skies to photograph or you need to filter out unwanted reflections. But polarisers can also spoil photos so they need to be used with care. So here is aneasy to follow illustrated guide to using a polarising filter.

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[John H. Maw]

Re: A guide to using polarising filters

Hi. My slight gripe is the almost universal (and unquestioned) assumption that circular (rather than linear) polarisers must be used with all modern cameras. In some cases it is so, but in many it is not. I have always used linear polarisers with autofocus cameras and have not experienced problems. The belief comes partly from the fact that the early AF cameras performed poorly with linear polarisers, but that was a long time ago. The reason why this is relevant is that circular polarisers are more expensive but less effective than their linear counterparts, so you get less and pay more.

Unfortunately, because the world and his dog believes that circulars are best, it seems impossible to get a coated linear pols. If anyone knows of any I would love to know.

One other factor is that polarisers should be checked once purchased as small manufacturing defects can produce distortion, even double imaging, in parts of the image. This is particularly easily seen when used with long focal length lenses and is most likely with very inexpensive polarisers although it can happen with even the most expensive ones.

[Ian]

Re: A guide to using polarising filters

John, I think you make some interesting points. I think I do have an old linear polariser somewhere. I'll hunt it down and try it out!

Ian

[Ian]

Re: A guide to using polarising filters

John, I think you make some interesting points. I think I do have an old linear polariser somewhere. I'll hunt it down and try it out!

Ian

I have found it, but it's 49mm; the smallest AF lens I have is 52mm; will have to resort to the Heath Robinson method for this

And there are no blue skies today - where are you today Mr.Blue Sky? (apologies to ELO)

Ian

[John H. Maw]

Re: A guide to using polarising filters

I have a 105mm Heliopan Kaesemann polariser you can borrow if you like. The drawback is that it weighs almost as much as the rest of my camera kit - only a slight exaggeration.

[Ian]

Re: A guide to using polarising filters

I have a 105mm Heliopan Kaesemann polariser you can borrow if you like. The drawback is that it weighs almost as much as the rest of my camera kit - only a slight exaggeration.

That will fit the business end of the Zuiko Digital 90-250 f/2.8

Ian

[John H. Maw]

Re: A guide to using polarising filters

There you go. Let me know where to send it and I will pop the filter into the post. I trust the lens is well made and can withstand the weight of the filter.

[Bob Ross]

Re: A guide to using polarising filters

HI Ian,
This is certainly a complex subject with lots of tips and tricks involved.
One that I read about, but never experienced is that with cameras that have hybrid WB, color shifts have been know to occur. The outside (ambient) sensor picks one WB and the interior sensor reads the polarized (enhansed color) light and the combination doesn't fit the mfr's adjustment curves. Using a preset WB solves that problem.
Bob

[Ian]

Re: A guide to using polarising filters

HI Ian,
This is certainly a complex subject with lots of tips and tricks involved.
One that I read about, but never experienced is that with cameras that have hybrid WB, color shifts have been know to occur. The outside (ambient) sensor picks one WB and the interior sensor reads the polarized (enhansed color) light and the combination doesn't fit the mfr's adjustment curves. Using a preset WB solves that problem.
Bob

Hi Bob, that would certainly make a lot of sense. I used to expect Polarisers to be neutral, but they hardly ever are in practice.

Ian