KevinLangston.com - Kevin's Photography Tips

kevinlangston.com: photography tips, filters

Things I've learned while exploring filters

Wide Angle Lens with filter cutting off corners

At the short end of the zoom, anything on the front of the lens can darken or even block the far corners of the view. I sometimes use a circular polarizer when shooting outdoors, resulting in some wideangle pictures with the corners noticably cut off. That's okay when cropping but can be an annoying artifact on certain beautiful blue skies. And the viewfinder doesn't show the shadow on most sub-full-frame DSLRs. It's easy to fix, just zoom it in a bit and the shadows go away. Alternatively, get one larger than the lens opening and get an adapter to match. And don't have them attached when they're not needed. That's a good recommendation for all filters, even the UV filter you may use just to protect the lens, reflections at night can be hard to track down...

A circular polarizer can slightly wash out the colors and modify the exposure. Check that, a well-traveled filter can do that. It can also pick up considerable glare. I never noticed the effect when the polarizer was new. Keep your filters clean and dry. And don't have them attached when they're not needed. Decent picture in the (hand-shaded) area, lots of glare below it.

It's tempting to use a polarizer whenever the sun is showing in the sky. It richens the colors and makes the sky a more dramatic part of the picture. But when used with a wide angle lens it can make the sky or water inconsistent because the light angles are quite different from one side of the frame to the other. Good, bad or indifferent; just be aware of the effect.

A graduated neutral density filter is an option for scenes containing both extreme light and dark areas, like sunsets. I was skeptical about Cokin's square filters attached to a round lens, but the ability to adjust the angle and location of the darkening within the frame is absolutely priceless. Again, get one larger than the lens opening and avoid the corner shadows. You can do some amazing things with them.

Note these two images showing one side darker than the other. I rotated the ND filter so the gradiation was vertical to highlight the effect. Notice the additional color in the sunset and the existance of the clouds which are almost completely washed out with normal metering. It's a great way to bring out detail by slightly darkening white-out conditions and letting the metering adjust to something more normal.

Note the more balanced metering in the ND-corrected photo below. It might have seen some benefit from another f-stop or two.

On Photography

You're not paying for the 30 minutes it took to do the job.
You're paying me for the 35 years it took to get the job down to 30 minutes.