Question on polarizer filter.

What kind is the difference between "Linear" and "Circular" when it

comes to a poloarizer filter?

 

It will go on a 50mm 1.4 and a 80-200mm 4.0 with a Canon A-1.

 

Thanks in advance.

Keith I'll let some one else explain the differance between the to but I will show you a page I posted to the Yahoo Canon FD grup that has a listing of Canon FD mount cameras and the type of polarizer recomended by Canon for that body. Not on the list are the FTb and FTB-n which both like the origional F-1 use Cicular polarizers.

 

The page can be found at:

http://f4.grp.yahoofs.com/v1/UOcQP6WggQuIIJT8lGZGtQ6ulz8ZDXYHsXHGFoaqO6IpNwAgrcyPnulgamumA_7YVYDcm1SZColktslCUvmsTtR_J4s/polarizing%20filters%20and%20canon%20bodies.jpg

Mark,

 

Thank you. When I listed the question, I failed to include another lens 28mm 2.0. Is it ok to use such a filter on a wide angle lens?

 

By the way, many months ago, I asked on the site what the difference was between the 28mm 2.8 and 28mm 2.0. You recommended that I get the 2.0 if I find a deal. Found one in excellent shape for $105.00 including shipping. Love it and still learning how to use it.

 

Thanks!

A polarizer on a 28mm lens should be fine. The wider the lens, the more chance of the filter entering the light path causing the corners of the frame to be darkened, "vignetting". You will need to test your lens to be sure, but also remember to only mount one filter at a time until you find out. Good luck!

One more personal comment about polarizers. I find them to be over-rated because they reduce contrast causing a loss in detail in shadows and creating an overall flattened effect. Use it sparingly to start until you get a feel for how it is going to affect a particular image. You will find them even less impactful with your two excellent primes which already maintain high contrast and excellent colour rendition. Good luck!

<I>only mount one filter at a time...</i>

<P>

The cheap solution to this problem is to mount oversized filters on a step-up ring. I buy filters for the largest lens diameter (in my case 67mm I think) and step up rings from all other sizes to that. That puts 67mm diameter filters on my 52mm diameter 28mm wide angle lens. You can stack several filters this way without vignetting, although I've never had occasion to stack enough of them to get close to vignetting. You also only need to buy filters in one size, which can be a big cost savings when you're talking about expensive filters like polarizers. You can buy quite a few step-up rings for the cost of one good polarizer.

Linear is fine for the A-1. Use a circular when using a T-90 or any EOS.

As for Johns comments, polarizers are used particulary with positive film to increase colour saturation and contrast. They are aslo brilliant for reducing or elliminating the reflection on water and glass.

I've always been told, and I think I read somewhere once, that linear polarizers degrade a cameras ability to auto-focus, so for auto-focus cameras you need to have a circular polarizer.