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DJMC
25th May 2011, 12:42 PM
I saw this on Ebay: http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=320701107288&ssPageName=STRK:MEWNX:IT

9.99 posted on a buy-it-now but not sure if it was linear or circular as the ad didn't say and it's not the correct box, so I asked:

"Just wanted to check it IS a circular polarising filter (CPL) as advertised and not a linear one (PL), before you send it out!
Many thanks,
David"

Seller replied: "Definitely a circular one! Thanks."

It's arrived, but it has 'PL-CIR' on the side of it (pic below).
Am I correct in saying it IS a linear filter, not a circular one, and the seller didn't understand?

1532

:confused:

Ian
25th May 2011, 12:45 PM
I saw this on Ebay: http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=320701107288&ssPageName=STRK:MEWNX:IT

9.99 posted on a buy-it-now but not sure if it was linear or circular as the ad didn't say and it's not the correct box, so I asked:

"Just wanted to check it IS a circular polarising filter (CPL) as advertised and not a linear one (PL), before you send it out!
Many thanks,
David"

Seller replied: "Definitely a circular one! Thanks."

It's arrived, but it has 'PL-CIR' on the side of it (pic below).
Am I correct in saying it IS a linear filter, not a circular one, and the seller didn't understand?

1532

:confused:

Not sure what the question is :) CIR means CIRcular :D

Ian

francois
25th May 2011, 12:57 PM
No problem, it is a circular polarizer filter. By the look of the box graphics, I'd say one from the 90's.

Re linear polarizers, you tend to find that only the inscription PL is written on the side as opposed to CIR PL or PL CIR so you cannot go wrong.

Little explanation on the differences between the two.

The first polarizers are called a linear polarizers. Perfect with all rangefinder cameras, view cameras and most manual focus cameras. They are called linear as the light waves coming out the back of them vibrates in one plane in a linear fashion.

Normal AF cameras use polarization tricks as part of the AF system. So using a regular linear polarizer would interfere with the focusing and metering functions of the caemra. That is why the circular polarizer type was developed, to bypass this problem.

For more in-depth explanation, check:

http://camerapedia.wikia.com/wiki/Polarizer

Ross the fiddler
25th May 2011, 01:01 PM
I think the PL means polariser & the CIRC as Ian says.

DJMC
25th May 2011, 01:19 PM
Not sure what the question is :) CIR means CIRcular :D

Ian

It's just that I'd seen a number of filters described as circular with a photo of 'CPL-CIR' and others with just 'PL' described as linear.

Thanks for the info all.

francois
25th May 2011, 03:49 PM
Yes, in this case CIR or CIRC doesn't mean circumcised ;)

Invicta
25th May 2011, 07:10 PM
I saw this on Ebay: http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=320701107288&ssPageName=STRK:MEWNX:IT

9.99 posted on a buy-it-now but not sure if it was linear or circular as the ad didn't say and it's not the correct box, so I asked:

"Just wanted to check it IS a circular polarising filter (CPL) as advertised and not a linear one (PL), before you send it out!
Many thanks,
David"

Seller replied: "Definitely a circular one! Thanks."

It's arrived, but it has 'PL-CIR' on the side of it (pic below).
Am I correct in saying it IS a linear filter, not a circular one, and the seller didn't understand?

1532

:confused:

Hi

There is a quick way to test it is a circular polariser.

Stand in front of a mirror and hold the filter in front of your eye with the camera thread towards you (ie as a camera would see it), you should see the reflection of your eye in the mirror. Now rotate the filter so the camera threads are pointing towards the mirror - if you see black then it is a circular polariser, if you still see your eye in the mirror it is a linear polariser.

DJMC
25th May 2011, 09:53 PM
Hi

There is a quick way to test it is a circular polariser.

Stand in front of a mirror and hold the filter in front of your eye with the camera thread towards you (ie as a camera would see it), you should see the reflection of your eye in the mirror. Now rotate the filter so the camera threads are pointing towards the mirror - if you see black then it is a circular polariser, if you still see your eye in the mirror it is a linear polariser.

It's black - hooray!!

*chr