Non-Circular Polarizing Lense. ???

[Vertifly 0]

Can anyone tell me if there is such a thing as a NON-circular polarizing lense?

I had the circular one attached to my GL2. As you may already know, a circular polarizing lense moves around. Therefore, it has some play in the lense. The weight of my wide-angle lense coupled with the polarized lense causes vibration (NO MATTER how much gaffers tape I put on it yes, I thought of that).

So, I'm thinking that I will need a fixed polarizing lense. Is there such a thing??? And where can I get one???

Thanks

[ffejdraga 0]

tape it in place.

simple, effective, and cheap.

jeff D-16906

[Squeak 17]

did ya read his whole post


Yes you can get polarisers that are not circular but they will be too combersome for skydiving.

You are not now, nor will you ever be, good enough to not die in this sport (Sparky)
My Life ROCKS!
How's yours doing?

[quade 3]

Actually, what you're talking about is a polarizing lens in a -rotating- mount. Almost all polarizers are mounted this way because, well, in order to take advantage of the effects of the polarizer, it must be rotated into the correct position, which will change depending on the angle to the sun.

The most common polarizing materials limit the vibrations of light to one specific linear direction -- let's call it "up and down". The rotating mount allows you to orient the polarizing effects "side to side" or any direction in between.

A -circular- polarizer is actually something quite different and change the vibrations in either clockwise or counter clockwise directions.

Now, here's the wierd part.

In order for most modern digital cameras to work correctly, the filters must be both circular and rotating.

More than you probably ever wanted to know . . . HERE.

quade -
The World's Most Boring Skydiver

[AndyMan 7]

Clicky no worky.

_Am

__

You put the fun in "funnel" - craichead.

[quade 3]

Fixed.

quade -
The World's Most Boring Skydiver

[jeiber 0]

Actually, the only difference between a linear polarizer and a circular polarizer is that the circular has two layers, a circular behind a linear layer (I think that's the order, I forget).

In any case, the circular should be used on AF cameras to ensure focusing and light metering are correct. Although I tried both on my F100 and didn't see a difference, linears can potentially cause focusing and metering problems on AF cameras. Looking at both filters, they are visually indistinguishable.

A very common misconception is that the 'circular' characteristic eliminates the need to adjust the ring in relation to the suns position. Not true - they don't put the rotating ring on there for fun!

Jeff

Shhh... you hear that sound? That's the sound of nobody caring!

[jalisco 0]

3M's got a pretty readable, brief discussion here:
"Types of Polarizing Filters"
(it shows the circular polarizer being used for a different (anti-glare) application)

[videointhesky 0]

I have been using a Circular Polarizing Lens
on both my video camera, 35 mm Minolta & 645 Pentax still camera's for sometime.
Always making sure that there is enough light to use them.

Here are a couple of 35mm shots using a
Circular Polarizing Lens

[Vertifly 0]

Yeah, it really make the difference. I've got some video over the Puerto Rico coast that will blow your mind. But the polarizing lense keeps vibrating.

Perhaps it just isn't meant to be for video. I do like how the color comes out though. Thanks.

[videointhesky 0]

Can you secure the lens so it will not vibrate?
I have done this in the past with a support of some kind under the lens and then use zip ties and gaffers tape to keep the lens stable. Now I have machined metal lens support. But I all I use is a top mount helmet set up. Not sure how a side mount would work with a lens support
if that is what your using.

Here are some pic's of my helmet with the top mount support

[Vertifly 0]

I've already tried gaffers taping it. Purhaps I just didn't use enough of the stuff. The area where the tape needs to go is a very tough area to get into. In other words, the wide-angle lens is BIG, the polarized lens is small, and the camera gets BIG again. This makes for a very unstable lens and difficult to secure so that it doesn't vibrate in freefall.

It doesn't sound like the option of a NON-Rotating lens is available. Hey, I will have to do what many thousands of camera flyers have done before me and GAFFERS tape it to death.

[quade 3]

Or . . . just ditch the polo.

quade -
The World's Most Boring Skydiver

[Vertifly 0]

Yeah, but the picture comes out SOOOO much better. Particularly when you are jumping in hazed conditions or when the backdrop makes for excellent eye-candy.

It is usually very hazy in Jersey (where my home DZ is) and when I go elsewhere the eye-candy is usually good too. I'll work it out somehow.

[kallend 1,644]

When I was in high school* we did optics as part of the physics course. Now it hardly even makes it into college physics.

* of course, optics was really important back in the "Dark Ages".

...

The only sure way to survive a canopy collision is not to have one.

[Gerry 0]

Quote

I've already tried gaffers taping it. Purhaps I just didn't use enough of the stuff.

Aside of the polariser being "fussy" in freefall and the points quad mentioned -

Not sure of the diameter of your p-filter but I had good luck in keeping the polariser fixed with a bungee. This was on a 52mm diameter filter.??

Blue Skies !
Gerry

"Living Well is the Best Revenge"

[Vertifly 0]

It's a 58mm I think. Could you explain, more clearly, how you bungee'd it? Or perhaps take a pic and post it? Thanks, I would try this if I could envision how you did it.

It is amazing how much different my footage looks with (and without) the P-filter on. All of my Peurto Rico footage is CLEAR, CRISP, and VERY COLORFUL - this is when I had the filter on, but the camera shake is a little bit annoying when you look at the video. While filming in Skydive Sobe, I thought the sky was LESS HAZY than PR and the movies do not come out nearly as good.

It also makes a HUGE difference with a 3-chip. because the clarity on this camera is SO good, I do not want to compromise its potential by not using the best tools. This is definitely going to require a fix.

[skysurfcam 0]

are you putting the filter at the end of the stack, or in the middle? Mine goes on the end, eliminating the shake probs...

Brother Wayward's rule of the day...
"Never ever ever go skydiving without going parachuting immediately afterwards."
100% PURE ADRENALENS

[Vertifly 0]

It has to go in the middle. The kind of lens that I own doesn't have threads on the outside. It sucks, but the lens is very good.