I've just been going through, cleaning and organizing the 100 or so filters I've collected over the years. A lot of Tiffen and Hoya, a fair number of Nikons, a few Vivitar/Promaster/Fotomate/Samigon, a Canon and Minolta or two, a couple of B+W and several Kenkos. Some of them are scratched, for which I can't blame the maker. Some of them are cloudy, for which maybe I can. Almost to exclusion, the cloudy ones are Tiffen, but then I have more Tiffen than others -- mostly I bought them (and Hoya) because the price was right. Many came in used, either on lenses I bought or from the usual sources.
There are two ways (maybe more) to make a filter: color the glass or sandwich a non-glass colored filter between two layers of glass. Tiffen uses the latter, and I suspect that's the source of the cloudiness. It's not on the surface of the glass and no amount of cleaning will remove it.
Of the filters currently available new, I have the following observations:
Nikon no longer makes a full range of filters, having abandoned most B&W and color correction filters as "not necessary for digital." Their older chrome/brass filters are very nice, but their black ones tend to bind more than others.
- Hoya still makes some colors (red, yellow, etc.) certainly more than Nikon. HMC are nearly as much as B+W non-coated. I haven't seen any pattern of problems with Hoyas, and the mounts are nice.
- Tiffen makes a good range of filters, but I suspect their quality at this time.
- B+W makes a complete range of filters, no questions on quality, but coated filters are ungodly expensive.
- Heliopan and Formatt, similar to B+W, possibly less extensive lineup.
- Other common names an unknown quantity (Marumi?)
- Lots of cheap filters available on eBay, quality suspect.
- Many cheap filters use plastic retaining rings that don't hold up. Loose glass is a problem in a number of them.
- Nikon uses spring-retainers in at least some of their filters, and when the glass comes loose (it will) there's no way to tighten them back down.
- Lots of used filters available from eBay and KEH, but I've gotten some bad ones (scratches or cloudy) so I'm reluctant to buy more.
- I've never used Cokin-style filters, the idea of putting plastic in front of the lens doesn't appeal. I have a few that came with other equipment and I'm not impressed.
The long and short of it is, I don't use filters unless I need them, and coating isn't always a concern (I know how to minimize flare) so I'll probably buy Hoya (non-HMC) if I can get the size/type I need, and B+W uncoated when I can't. New, too, unless I really trust the seller.
I probably could have saved some money in the long run had I figured this out 40 years ago, but hey, live and learn.
Ulysses.