chapjohn Loc: Tigard, Oregon

I am going give a different answer than most others have. My suggestion is to get a circular polarizing filer and a variable ND filter. This will give you the most flexibility. Stack them to get the most benefit. These filters are doing different things to the light. The CPL is making the light better and the VND is reducing the amount of light. Most of the great images of water and waterfalls are made using a CPL filter.

98% of my images are made outdoors and I always use a CPL. It will help enhance colors and reduces glare from water. CPL also help to shoot through glass, but you can still get unwanted reflections in the glass. The direction of the light is something to always give attention when making an image, however, the CPL will still give its benefits regardless of the light direction.

I use the Promaster HGX filters. These filters are made by Murami and at a good price (less than Murami brand).

jcboy3

Highly recommend against stacking VND and CPL. VND works by rotating polarizing filters, CPL will screw that up big time.

SteveLew Loc: Sugar Land, TX

We visited Big Bend, NP last year. Most of my shots were during the dream hours. However, the shots that I took between the dream hours I used a Lee big stopper 10 stop filter. My shots during the day cam out great and they did not look like noon shots. I first focused without the filter and set up my shot normally. Then set my camera to Bulb placed the filter on my camera, blocked my eye viewed with dark tape and set my time exposure time with an phone app. and used a remote to trigger my camera. By using the darkest filler you can emulate photos that appear to taken either earlier or later in the day. Tiffen filters are fine but I would use the darkest filter or combination of filters during daylight hours.

SteveR Loc: Michigan

That certainly clarifies things!!

amfoto1 Loc: San Jose, Calif. USA

What, exactly, are you trying to accomplish?

The usual purpose of a strong ND for still photography is to shift the exposure setting range in too-bright conditions. That would be done to allow a slower shutter speed (for deliberate blur of moving objects, such as flowing water) or to allow use of a larger aperture (for deliberately shallow depth of field effects, such as a more blurred down background).

For still photography, it's usually a rather strong filter that's needed.... 6- to 10-stop. Then the ISO, aperture and shutter speed can be varied to achieve the desired results.

The 1-, 2- and 3-stop filters are more commonly used for video work, where finer control over exposure with filters is needed because there's less flexibility among the other exposure settings (especially shutter speeds).

Try to avoid stacking filters, if at all possible. Every additional "layer" costs you some image quality. On really wide lenses, stacking also will often cause vignetting issues.

Don't confuse ND filters with Graduated ND filters, either. Grad ND are used to balance a too-bright sky with the rest of a scene. The filter is half clear and half neutral gray to reduce exposure only on part of the image, with some sort of smooth transition zone in the middle. This is best done with the rectangular filters in a holder mounted on the lens, which allows positioning the "horizon line" of the filter to match the scene. (A round, screw-in Grad ND forces you to put the horizon line in the center of every images, which very often isn't ideal.) Graduated ND filters most often are used in 1-, 2- and 3-stop strengths (2-stop is probably the most frequently used). With digital imaging you can actually do much the same... possibly even better... with a multi-image post-processing technique. If nothing is moving in a scene, take two shots at different exposures and combine the "correct" portions from each into a single, final image later in Photoshop (or whatever). Or, if subjects are moving it's possible to multi-process a single image (usually best done with a RAW file).

If the bright conditions were causing glare problems, and you weren't trying to use exceptionally slow shutter speeds or especially large apertures, a Circular Polarizing filter might have been what you wanted. A CPL basically filters out oblique light, which has the effect of deepening the blue of the sky, making clouds "pop" better, and improving overall color saturation of many scenes. They also can reduce reflections off water, glass, foliage, eyeglasses, skin, etc. A CPL also will reduce light entering the camera by between 1 and 2 stops. So it can have similar effect to one of the weaker ND filters. A CPL remains one of the most useful filters to have available. Unlike most other filters, many of a CPL's effects cannot be replicated very effectively in Photoshop (or whatever).