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OzOutbackGirl
01-12-2010, 4:48pm
Hi everyone, I have a very cheap CP Filter (a Massa brand which was $8 on EBAY) which I have been using for about 6 mths and liked the effect very much. Since joining this forum and studying lots of photographic books, I have learnt that you should not scrimp on Polarising filters coz they reduce the quality of your images. I hadn't really noticed this except on photos that I now understand I shouldn't have been using a PF on (e.g. zooming in on animals etc).

I have since purchased a good CP Filter (Hoya Pro1) and the question I have is this: The difference in polarisation between the two is massive. The cheap one is very obvious when you turn the filter but the expensive one is very subtle. So subtle in fact that it's hard to tell the difference where cloud saturation etc (popping of colours as they say) is concerned. Is this normal? The more expensive one does reduce reflection to a degree but not as much as the cheap one?

Can anyone enlighten me?

junqbox
01-12-2010, 5:09pm
The difference possibly comes more from time of day and direction the camera is pointed in. Polarisers work in cutting the glare when pointed 90 degrees to the sun (could be wrong on actual degrees/direction). Some conditions will apply gentle polarisation, others will produce a dramtic effect.
What you will notice is that your shots are likely to be sharper and a more consistent application of the effect across the whole image.

OzOutbackGirl
01-12-2010, 5:39pm
Thanks Junqbox for your explanation. I had already tested it in the same conditions and the cheaper one has a more dramatic effect but when I actually study them closer, the picture taken with the cheaper CPL actually has a yellowish tinge and you are right....slightly less sharp. The more expensive one seems to have a more natural colour. In the bin the cheap one can go :-)

jjphoto
01-12-2010, 9:50pm
Make sure you are holding the filter correctly if you are simply holding it to your eyes to see the effect. Of course it can only be fitted to the camera one way, but if you look through the filter from the 'wrong' direction then the effect is quite different.

It's interesting that one of the filters has a greater polarising effect. Not sure what that's about.

JJ

OzzieTraveller
03-12-2010, 8:41am
G'day oog

I find your post very interesting in that it tends to confirm some thoughts & observations of my own

Firstly - as mentioned above, a pola filter works to its best when it/the camera is positioned at 90deg to the sun's rays ... ie: if the sun is perfectly overhead, then pointing towards the horizon, any horizon will be 90deg, otherwise in am or pm, pointing the camera sideways to the sun and getting the shadows along with the sky will get you as much pola effect as it possible 'then & there'

Secondly - the pola filter is extremely good at removing reflectons from shiny surfaces ... glass windows, table surfaces etc

I would like to invite you to test [and report?] some experiments with each filter - something that is repeatible for accuracy perhaps
Maybe a shot of your car & the reflections on the windows - it will show both reflection reduction & maybe, a colour change from a known coloured object

Hope this helps a bit - over to you
Regards, Phil