POLARIZER changing color of white wall??

Hi Buck. I don't think the problem is widespread. It might be in the polarizer, even though I had all 3 polas having problems. I do not know what I did, but I seemed to have fixed it in one pola. Strange but it works fine today, I'm not sure what I did. However, at the same time, I tried my old Schneider 4x4 true pola that I've used for years and it has the same color shift problem. So now I have one pola that works and one that doesn't. Now, even more of a mystery - but I'm glad it works now with my new pola.

I've forwarded my problem to sony, and have not heard back. Let me know if you hear anything. Also, if you ever come down to the bay area (San Mateo) - let me know, I'll be happy to show you my tests.

PS - beautiful nature footage - email me at wavesdvd.com.
 
As I said, prism or 3CCD. Let us know what the Sony rep says. It isn't a Sony problem. It might be more akin to the rolling shutter issue. It simply cannot be completely resolved.

By the way, I've had this with Tiffen and Schneider TruPolas - all the way down to an inexpensive linear pola - on F900; HPX; HVX; DVX.

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Problem Solved - But Why?!

Problem Solved - But Why?!

GREAT NEWS - PROBLEM SOLVED - BUT WHY?

Ok, this does not make a lot of sense to me. I've been wondering what I've been doing that could have fixed the camera... Well, I tried the camera this morning with my $200 circular Rodenstock circ. pola and it did NOT WORK - I had my cyan / magenta color shift?! But it did last night? But this morning it was ALSO vinyetting - last night it wasn't... Hmmmm - A CLUE...

Could I have flipped the filter (I do not have my pola screwed in, rather it is sitting in the step down ring of my Chroszeil mattbox. So, I popped it out (which I had done the night before) and flipped it - popped it in... NO COLOR SHIFT AND NO VIGNETTE - SINCE IT SAT A FEW MM CLOSER TO THE LENSE!!

So, I tried it with my Scheinder 4x4 circular pola and it FAILED... both front and back - flush to the lense - (It still works fine on my pd-150). hmmmm. - A MYSTERY.... even after re-color balanced - all manual settings. and camera turned on and off.

Now the Tiffen screw in - WORKED when screwed in and FAILED when flipped and held by hand in front backwards.

SO CONCLUSION - THERE IS A FRONT / BACK TO SOME POLAS. Maybe there is a glare reflecting coating that is effecting the camera when its flipped. Why the Schneider fails both ways - I dont know and that is disturbing as it works on my PD-150.

Anyway - TEST your polas and make sure they are faciing the correct direction.

Thanks everyone - anyone who can tell me why? Chime in - they are all circular polas (no linear polas) and all $150+ dollars.
 
Well.....

(This is thinking out loud time, so might be way off base)

It could be a problem caused by the light's distortion through the filter. Perhaps it's not front and back but distance from the lens that's the issue. You could try two tests here - one, mount the filters a ways away from the lens, but exactly perpendicular (i.e. use an empty filter ring or a spacer) in the orientation that they worked in (i.e. "forwards") and see if the effect comes back. Two, try angling the filter slightly (particularly the Schneider) and see if this reduces or removes the effect.

Not sure why it would change with the angle of polarization, but it would explain why the Schneider (which will be a little thinker @ 4mm) did not produce good results whilst the screw-ins did.

Just a thought...
 
This has been a very useful conversation.

I had the same magenta problem a while back. I was using a Schneider 4x4" Circular True-Pol . Taking a close look at it reveals a label on one side "THIS SIDE OUT". Well that makes a difference.

Thanks for the help.

Pete
 
Mate,

I had a major job a few weeks back with my JVC HD251, and the same weekend I did a wedding, I noticed this purple/magenta colour shift to everthing, I've never noticed it before. I was thinking maybe it was a colour matrix shifted on the camera. I thought maybe the cleaning agent I used on the tiffen polariser had stripped something and caused a colour shift.
But I never would have thought a polarizer could have this trait. I'm pretty jack angry with tiffen, and therefore I suppose other filter companies. Maybe they do warn you not to use their filters with 3ccd cameras or whatever. But one should reasonably expect that such a thing would not occur.
My footage looked shocking, people with dark navy blue shirts came out pink in colour!
And I had the green thing happening as well. It was too major a job to colour balance everthing especially editing in standard 8bit hdv.
hmm
sorry for the dummy spit
 
Thanks for the confirmation. If more people would be brave enough to post some of these strange problems, we might all avoid a few costly mistakes. As I said, all 3 filters worked fine both forward and backward on my Sony PD-150... so it was a huge surprise to see such craziness on the EX1. Glad to hear it happens on other cameras and filters too.

Now, if only I can remember to take the lense cap off. :huh:
 
Well, it's good to know it's not going to be a big issue for me after I match the right filter/combo. I never did hear back from Sony about this. I emailed a specific person so maybe he's on vacation or something. Or maybe not. I'll give him the benny of the doubt.
 
That's definitely something all EX1 users need to be aware of: It's probably the beam splitter for the imager system that's forces the use of a circular polarizer.

And lucky for us we're setting up polarizers and not Claymore mines that are clearly marked, "This Side Toward Enemy". :laugh:
 
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