Filters: Polarising against ND

[kohck]

Dear gang,

I want to buy a filter but i cannot decide between a polarising filter or a ND filter.

A poloarising filter make the blue sky and the greenery more defined and it does look better. My question is: will it reduce the amount of light coming through the lens? If it does, i must be more alert towards low light condition. Does it reduce glare or reflection from glass?

A ND filter seems to be useful only as a lens protector. Does it reduce glare or reflection from glass? It is say to be useful at high altitudes where it reduces something?

[catchlights]

Originally Posted by kohck Dear gang, I want to buy a filter but i cannot decide between a polarising filter or a ND filter. A poloarising filter make the blue sky and the greenery more defined and it does look better. My question is: will it reduce the amount of light coming through the lens?

Yes, it reduce exposure 1½ to 2 stops.

Originally Posted by kohck If it does, i must be more alert towards low light condition. Does it reduce glare or reflection from glass?

Yes, to a certain extend, but will not eliminate hot spots and metallic reflection.

Originally Posted by kohck A ND filter seems to be useful only as a lens protector.

No, it just it reduce exposure, so it call Neutral Density Filter.

Originally Posted by kohck Does it reduce glare or reflection from glass?

No.

Originally Posted by kohck It is say to be useful at high altitudes where it reduces something?

I think you mistaken ND filter for UV filter, many people use UV filter as lens protector. cos it cut down nothing except UV ray, and it is useful in high altitudes.

[garytan007]

Originally Posted by kohck Dear gang, I want to buy a filter but i cannot decide between a polarising filter or a ND filter.

Catchlights is right.
I think polarising filter is what you looking at.
ND filters are used to cut down lights so as to use a bigger aperture for greater DOF. Usually a stand-by for me or commercial photographers in case art directors want a certain effects.

[yyD70S]

If you are to buy only one, go for the Polarizer as it's effect is something that is almost impossible to simulate in pp. Furthermore, if you get a good one (e.g. Nikon, B+W which is amlost neutral, ie, almost zero colour cast) it can act a a 2-stop ND filter in emergencies.

[kohck]

Dear Gang,

Let me see..... 3 questions

How about UV filter? It is only useful as lens protector and at high altitudes as it cuts now on UV light. It does not cut down on the amount of light coming in. It also does not improve the photography results.Right?

For poloarising filter: i have to remove the filter at night as it cut down on the amount of light entering the lens. It improve the photography results in the day as it make the blue and green more intense. But at night, it make the photography worse as it reduces the light coming in by up to 2 stops. Right?

How do you use the camera with the ploarising filter in the day? i heard that you must stand with the sun to your left or right for best results. The sun should not be behind or infront. Right?

[yyD70S]

A soft guide on Polarizers:

http://www.luminous-landscape.com/tu...larizers.shtml