Is a linear polarizer okay?

[Stafford Mead]

Hi, I recently bought a used Rokinon 500mm f6.3 mirror lens for my Canon XSI to play around with. It was good price and i'm having a good time with it. I have a chance to buy a 95mm linear polarizer for it. Since the lens is manual focus will it be okay on my camera as long as i don't expect it to try and auto focus? Some things i've read say no the camera will give erroneous results. I'm just not sure if it will be okay for my purpose. Any help would be appreciated.

 

[sween]

My first thought would be to turn off auto and manually expose. If you're hitting manual focus, you might as well do the full deal and go manual exposure. It really ain't that hard at all. I did a lot of last weekend with my D200 and circular polarizer. Linears I know little about, never used one.

 

[Plato]

Hi, I recently bought a used Rokinon 500mm f6.3 mirror lens for my Canon XSI to play around with. It was good price and i'm having a good time with it. I have a chance to buy a 95mm linear polarizer for it. Since the lens is manual focus will it be okay on my camera as long as i don't expect it to try and auto focus? Some things i've read say no the camera will give erroneous results. I'm just not sure if it will be okay for my purpose. Any help would be appreciated.

I don't know if your camera has "live view" on the monitor but, if it does, it won't work properly. You'll need to focus mechanically through the viewfinder, which is tough without a split image focusing screen. Also, the camera's metering system will not work properly.

 

[Stafford Mead]

Thanks for the info. When i use this lens i set the camera in a full manual mode. Focusing isn't that hard if you take a little time. I was just wondering if i set the camera on manual mode and select my settings will it work or will the polarizer somehow mess it up? Hate to buy it at any price if it doesn't allow me to take a picture. Any other thoughts?

 

[KmH]

You'll be able to take pictures.

You won't be able to rely on the in camera exposure meter to select the right manual exposure settings to use. With tiem you'll gain enough experience to judge the correct settings pretty closely.

Exposure will be totally based on your Mk I eyeballs.

 

[Garbz]

Yes it will work. And yes you can save $5 on a polariser and manage to wipe out years of research that make the DSLR's modern focusing systems and exposure systems so great to use.

I'm happy to use manual focus too, but screw being forced to do it because I don't buy the right polariser. May as well throw my D200 away and buy a Nikkormat F

 

[Plato]

May as well throw my D200 away and buy a Nikkormat F

I wouldn't do that. I've heard that the Nikkormat had a lousy sensor!

 

[ErectedGryphon]

The way I understand it; you bought Rokinon 500 mm f/6.3 Mirror Lens for Canon EOS | Overstock.com and someone if offering you a Linear Polarizer at a discount price.

The lens does not Auto focus, so we don't need to worry about its effect on auto focus.


Circular Vs. Linear Polarizers


There are two types of polarizing filters available — linear or circular. Linear polarizers are more effective and less expensive than circular ones. But circular polarizers are needed with just about any camera that has a through-the-lens metering system, or auto focus.

The reason for this is that both of these systems use semi-silvered mirrors to siphon off some of the light coming though the lens. If that light is linearly polarized it renders either the metering or the autofocus ineffective. This means that you're going to have to buy circular polarizers unless you're shooting with a pre-1970's camera, or a view camera.

Source: Polarizers

P.S. Garbz; Go ahead and toss it, everyone knows that Nikon is only good as a subject for Canon. :mrgreen::mrgreen:

 

[Garbz]

Ouch!