Polarizer!! HOW?

[hao]

I heard that when using a polarizer, you should not aim your camera to the sky and adjust your CPL to get the darkest sky (it is what I have been doing). What you should do is to look at something with reflection and rotate your CPL to minimize the reflection from the subject. How do you use it? What I dont get is why cannot you just get a dark sky in the viewfinder, which will turn out to be a very blue sky in the image. Someone said it is wrong. But I dont know why.

The other thing is that when using CPL, why do you do a negative exposure compensation? I assume you are metering with the CPL on the lens, and the CPL already darkens what the camera sees, so you should get a correct metering reading for the CPL-added scene. It is mentioned here in this video:


If anyone can provide a very good source illustrating how to correctly use a CPL, that would be also very appreciated.

Thanks for reading my questions and your input.

 

[Garbz]

NO what you should do is point the camera at the subject and adjust the polariser to make the image look like YOU want it to. If someone ever tells you how to use a polariser, punch them in the face.

Same with exposure compensation. I didn't watch the video, but does your image come up over exposed? If not and some guy tells you to underexpose it recommence the punching.


Nothing annoys me more than someone showing me an image that looks like crap, they don't like it themselves, and then saying oh but I was TOLD this is what to do.

 

[Plato]

I heard that when using a polarizer, you should not aim your camera to the sky and adjust your CPL to get the darkest sky (it is what I have been doing). What you should do is to look at something with reflection and rotate your CPL to minimize the reflection from the subject. How do you use it? What I dont get is why cannot you just get a dark sky in the viewfinder, which will turn out to be a very blue sky in the image. Someone said it is wrong. But I dont know why.

The other thing is that when using CPL, why do you do a negative exposure compensation? I assume you are metering with the CPL on the lens, and the CPL already darkens what the camera sees, so you should get a correct metering reading for the CPL-added scene. It is mentioned here in this video:
YouTube - DSLR Tips: Using polarizing filters

If anyone can provide a very good source illustrating how to correctly use a CPL, that would be also very appreciated.

Thanks for reading my questions and your input.

1) You can use a polarizer to darken the sky if you wish.

2) You can use a polarizer to eliminate reflections if you wish.

3) If you're using the correct polarizer for modern SLRs, i.e. a circular polarizer, there is no need for you to do any exposure compensation unless you want the photo deliberately darker or lighter than "normal." The camera will read the exposure properly. If you happen to have an old linear polarizer, this response is out the window and your autofocus might also get messed up.

4) I agree with the points that Garbz made.

 

[Dwig]

NO what you should do is point the camera at the subject and adjust the polariser to make the image look like YOU want it to. ...

Correct.

Before you decide how to use a polarizer, but must decide why you are using a polarizer. If you can't decide why then you can't determine how so you should leave it in your bag and shoot without it. Its your decision, and only your decision, why.

 

[Plato]

NO what you should do is point the camera at the subject and adjust the polariser to make the image look like YOU want it to. ...

Correct.

Before you decide how to use a polarizer, but must decide why you are using a polarizer. If you can't decide why then you can't determine how so you should leave it in your bag and shoot without it. Its your decision, and only your decision, why.

Good point.

 

[tirediron]

A quick and dirty on CPOLs: Compensation is NOT required. Meter with the filter on the lens; you'll lose between one and two stops of light depending on the filter. To gain the maximum effect, remember that the sun should be lower in the sky (early morning/later afternoon) and at ninety degrees to the lens axis.

 

[hao]

thanks for your comments everybody:thumbup: