Circular or linear polarizer?

[shawntim]

I'm thinking of getting a polarizer. I only know that polarizers can cut glare and reflection off shiny surfaces.

But recently I read that there are actually 2 - Circular and Linear. What's the difference ? When do I employ the correct filter ?

Roughly how much for a 52mm?

 

[soybean]

Circular PL is for using with SLR cameras. Linear can only be used with Non-SLR or SLR-Like digital cameras like Minolta D7. The difference is that most Non-SLR or SLR-like digital cameras use different Autofocsing technologies. A linear PL on a SLR cameara will render the camera AF system unusable. A non-coated 52mm C-PL from HoYa is typically less than 40S$. But a Multi-coated B&W C-PL can burn your pocket.

 

[lefei]

shawntim,
I think there are a couple of threads on the differences of the Cir-PL ana Linear-PL. So a search

 

[Midnight]

...some examples of these threads being:

http://forums.clubsnap.org/showthread.php?s=&threadid=13512
http://forums.clubsnap.org/showthread.php?s=&threadid=12644
http://forums.clubsnap.org/showthread.php?s=&threadid=7544
http://forums.clubsnap.org/showthread.php?s=&threadid=9100

I think there really should be a FAQ on things like these.... ;p

 

[shawntim]

cool!! thanks thanks !

 

[mervlam]

Originally posted by soybean
Circular PL is for using with SLR cameras. Linear can only be used with Non-SLR or SLR-Like digital cameras like Minolta D7. The difference is that most Non-SLR or SLR-like digital cameras use different Autofocsing technologies.

not really... u can a linear polariser on a manual SLR or on AF cameras that dont use TTL (through the lens) autofocussing system

 

[shawntim]

sorry, i have another question. Visually, does it matter if the PL-CIR is not the outer most lens ?

I'm thinking since I'll be using PL-CIR more often, i get one size fitted for my camera, but if i want to get a TC or WA, thinking of getting a wider rear element (hence larger front element) and attach it to my camera like this.

camera > UV > PL-CIR > bigger rear element TC or WA.

my concern is that the turnable part of the PC-CIR may not be able to stand the weight of the TC or WA.

 

[mervlam]

why would u want to do that???

a UV filter is often used as a protective glass to the front coating or element of ur lens.

in the same sense, a polariser should only be attached to the front

 

[Adam Goi]

Originally posted by shawntim
sorry, i have another question. Visually, does it matter if the PL-CIR is not the outer most lens ?

I'm thinking since I'll be using PL-CIR more often, i get one size fitted for my camera, but if i want to get a TC or WA, thinking of getting a wider rear element (hence larger front element) and attach it to my camera like this.

camera > UV > PL-CIR > bigger rear element TC or WA.

my concern is that the turnable part of the PC-CIR may not be able to stand the weight of the TC or WA.

Hm...interesting...I've never heard of that there are threads in front of the polariser that allows one to stack other filters and such...something new?

 

[mervlam]

my polariser (cheap cheap Hoya Standard) has a front thread, but i dont stack with another filter. can cause vignetting

 

[Adam Goi]

Originally posted by mervlam
my polariser (cheap cheap Hoya Standard) has a front thread, but i dont stack with another filter. can cause vignetting

:embrass:

 

[shawntim]

that's why i'm thinking of getting a TC or WA with wide rear element to as to minimize vignetting.

my idea to to put it (ok, w/o the UV) on my camera, then attach at TC/WA on it.. in that way i just have to buy 1 size, instead of 2.

so my concerns are either 1- image quality, 2-strength of thread to hold equipment.. just need some verification lor..

 

[shawntim]

i just got a 52mm polariser.. but it causes vignetting when i stack it with my 52mm UV filter on my 602.. funny that when i stack a thicker +10mm, it didn't give me that vignetting.. i'm so disappointed.. am i the only one with this problem?

 

[mervlam]

that's because ur +10 macro filter has different optical characteristics from the uv filter.