CPL Filter gone bad?

[Stephen13]

I recently purchased the A119S for my wife along with a CPL filter. We were cleaning our cars yesterday and I removed the cam to clean the inside of the windshield. Since I had the cam out I thought I would also clean the lens and filter. The wife asked me about the filter so I explained it to her and went to demonstrate how it worked on our computer screen. I did this same test when I first got the filter to see how it worked. As expected rotating it darkened the image on the computer screen. When I went to do the demo for my wife the filter no longer darkens the image. Rotating it CW gives the image a slight blue tint to it and rotating it CCW gives a brown tint. The image no longer darkens at all as it did when I first purchased it. Anyone have any idea what is going on here?

 

[Stephen13]

DOH! Never mind. I didn't realize I was looking thru the filter from the wrong side.

 

[SawMaster]

Well we're all human and what matters most is that you got it all resolved. May all of you future problems be this easy to handle And welcome to DCT

Phil

 

[Stephen13]

Thanks for the welcome.

I'll be sure to pay closer attention next time.

 

[Nigel]

A more interesting demonstration of it removing reflections is to look through it at your reflection in a mirror, one way around you can see your eye, the other way you can't!

 

[Sutton]

A more interesting demonstration of it removing reflections is to look through it at your reflection in a mirror, one way around you can see your eye, the other way you can't!

Great tip never thought to do this thanks

 

[Rajagra]

A more interesting demonstration of it removing reflections is to look through it at your reflection in a mirror, one way around you can see your eye, the other way you can't!

Does that really work? I thought mirrors gave the "wrong" type of reflection, having a mirror-silvered layer on the back of the glass.

Edit> Ah, I've worked out what you mean - flipping the filter and looking through from the other side. That works on the CPL I just tried. Rotating it around the optical axis has no effect though.

I'm still not sure why you get a completely black image looking one way, but it definitely happens. I must try this with a regular polarising filter (not circular.) I'm sure it will just make your eye look 50% darker however you position it.

 

[Nigel]

Does that really work? I thought mirrors gave the "wrong" type of reflection, having a mirror-silvered layer on the back of the glass.

Edit> Ah, I've worked out what you mean - flipping the filter and looking through from the other side. That works on the CPL I just tried. Rotating it around the optical axis has no effect though.

I'm still not sure why you get a completely black image looking one way, but it definitely happens. I must try this with a regular polarising filter (not circular.) I'm sure it will just make your eye look 50% darker however you position it.

It has to be a CPL for that trick, polarised sunglasses don't do it

I think the reason it works can best be described as magic!