amfoto1 Loc: San Jose, Calif. USA

Several things I've read online seem to suggest a 6-stop filter is a good choice, if wanting to only buy one. I don't have any links to point to, but if you do a search you can probably find some info.

B+W filters are mostly what I use. You'll find four grades of them, all using high quality Schott glass and all using brass frames to reduce chance of galling and filter getting stuck. I don't know what size you need, so I'm citing prices for a fairly common 77mm diameter.... you can expect smaller ones to cost less or larger ones to cost more.

- "SC" are single coated and use a standard frame (for outdoor use, I recommend multi-coated).... $93

- "MRC" have 8-layer multi-coatings and standard frame, which is pretty low profile.... $136 (B&H Photo)

- "F-Pro" seems to be a new label for MRC, with same 8-layer multi-coatings, glass & standard frame.... $ same as MRC.

- "XS-Pro" top-of-the-line with 16-layer "nano" multi-coatings that are more dust, fingerprint, water resistant & easier to clean, as well as a slimmer frame as might be needed for ultrawide wide angle lenses... $161 (B&H Photo).

Note: There's greater difference between B+W MRC and F-Pro Circular Polarizing filters. The F-Pro C-Pol are "High Transmissive", while the MRC are not. There appears to be little or no difference between B+W MRC ND and F-Pro ND. "MRC" or "Multi-Resistant Coatings" label has been used for many years, while the "F-Pro" designation has been added more recently.

Breakthrough Photography filters seem pretty good, too. They offer two grades I'm aware of:

- "X2" use "AGC" glass, which I suspect is good quality "Asahi" optical glass. It is 8-layer multi-coated and, I think, uses an aluminum frame that's fairly low profile... $99 (Adorama)

- "X4" use Schott glass, 16-layer "nano" multi-coatings and a slim brass frame... $169 (Adorama).


EDIT:

"Variable" ND filters come in two varieties.... the expensive ones that really suck and the super expensive ones that suck a bit less. You can find them for prices similar to above... maybe even less. But, be warned, those will be the first type.... the ones that really suck. They'll have uneven effects, add tints to images and may degrade image quality in other ways. They also will often not be multi-coated. The more expensive ones can be upwards of $200, $300 or even $400 in 77mm size, will be multi-coated and less degrading to images... are less likely to do so, but aren't entirely free of uneven effects or possible tints.

Someone also suggested buying an oversize round filter and using step rings. That's a money saving scheme. But the problem is with most modern lenses it will make it impossible to use the matched lens hood... which is important to shade and provide physical protection for the lens and the filter! You'd also need a different size lens cap for storage, unless you faithfully remove the filter each time you put the lens away.

I used step rings to reduce the number of filters I had to buy, back when I shot film in the last century. I had thirty or forty different types of filters, which really added up when you had to buy them in a lot of different sizes. However, with digital so few filters are needed.... mostly just C-Pol, ND in one or two strengths, and maybe a UV/Clear "protection". To me it just makes a lot more sense to buy the correct size filter... and be able to use both the lens hood and cap.

Finally, yes there are oversize rectangular and square filters that fit into holders that attach to lenses with adapters. Those are rather bulky, difficult to shade well and protect from oblique light or physical damage, and are expensive. Used to be they weren't multi-coated and only available in optical plastic. But now, if your checkbook balance is big enough, you can find them made with quality glass and multi-coated. No thanks. I've put mine away (only keep them in case I get out a film camera and shoot with it... which doesn't happen very often). Several sizes of round filters serve my needs well and fit into my bag a lot better.

You should consider what lens you're mostly likely to want to use with an ND filter. For example, I'd have little or no need for an ND with my telephotos, but can see uses for an ND with some of my wide angle lenses.

billnikon Loc: Pennsylvania/Ohio/Florida/Maui/Oregon/Vermont

I like the BIG STOPPER, a 10 stop ND filter I use most often. I like it because once I get my exposure to 1/30 sec. at most any F stop (without the filter attached), I then know my correct exposure with the 10 stop filter will be 30 seconds. Make sure after you focus and attach the filter, you turn off the auto focus of the lens and make sure you cover the eyepiece during the exposure. A tripod is also recommended unless you are superman and can hold anything drop dead still for 30 seconds.

MrBob Loc: lookout Mtn. NE Alabama

That is good advice about computing an easy to get exposure and then just multiply by the exposure difference... If you carry 3 NDs you only have to remember the 3 longer settings from your easy to get reference setting. Sure beats having to go to an App, a cheat sheet , or the 10 finger method.

cambriaman Loc: Central CA Coast

As in all things photographic......there IS NO single choice!

Dennis833 Loc: Australia

I carry a 5 and 10 stop but hardly ever use the 10. I find the 5 stop is great for waterfalls and landscape use. The Hoya Pro ND32 is excellent and not very expensive.

User ID

Get a cheap one. You'll be sick and
tired of Fuzzy Water pix soon enuf.