Polarizer filter for wide-angle lens

I just bought a wide-angle zoom lens (17-40mm L Canon). I wonder

which polarizer filter is better: Hoya circular polarizer or Sanpak

circular polarizer?

which brand name is good for telephoto zoom lens?

 

Thanks,

 

Dennis

Probably the Hoya, though I would choose a Heliopan circular polarizer over either.

 

Depending on which camera you are going to use (24x36mm or the smaller sensors in the

300D, 10D, 20D, D30, 1D, 1D mk.II, etc.) -- and hence which size format you need to

be

aware that if you want an even polarization effect across the frame you won't be able to

get that if you choose an angle of view slightly greater than what you get with a 28mm

lens on a 24x36mm format -- which will just barely include the 17mm setting on the 17

-40mm if it used on a 20D/10D, etc.

I got digital rebel (300D). Are you saying 17mm is the wide-angle limit for this sensor?

No, you can use wider angle lenses on any camera, just be aware of potential undesirable polarizer effects on super wide angle lenses.

 

Ellis is just saying that uniform polarization for field of view angles greater than 74 degrees is problematic (a subjective opinion based on his vast experience). The effect shows up as a gradient (gradual change) in shading that is much more pronounced the wider the FOV (and it shows up at narrower FOV angles, just to a lesser extent).

 

74 degrees is FOV for a 28mm lens on 24x36 full size frame which is roughly equivalent to 17mm lens on your 1.6x crop factor sensor.

 

The real point is that a polarizer on a 17mm lens on a full frame body WILL have a considerable and pronounced shading gradient.

I see. I will go for Hoya filters soon.

 

Thanks,

 

Dennis