Filter Quality

Hey - after not doing anything for years in photography other then PS, I am now refilling my camera bag. I need to purchase filters and the price point varies dramatically from manufacture to manufacture. Optically, is there noticable difference in the quality of these filters. I am talking about the typical suspects here, Tiffen, Hoya, and B+W. Thanks for any advice here.

For screw-in filters any of those makes will be of good quality.

If you use a lot of filters then you can consider Lee, Chromatek or Cokin. (going from the most expensive, Lee to the cheapest, Cokin!). They are the square filter system, where each filter slots into an adapter, screwed on to the front of the lens.

I had the Cokin system before but it is missing with half of my old equipement - probably in a box somewhere. Is there an advantage to the square filters over screw mount? I had planned on just doing screw mount as most of my new lenses are 77mm. thanks.

Boy will this question open a can of worms. BUT, here is my take.
The 3 manufacturers you mentioned would be the most common and well known for their quality of filters. I would stick with them. You may not know what you get with other brands. These will generally be cheaper than a Canon branded filter that is probably made by one of these folks anyway.
Unless you are a total pixel peeper and are looking for details that most casual observers will probably not notice, don't buy the top the line filters from any manufacturer. If you and others are not going to notice the difference in pictures, why spend the extra money. Get a level that has some form of multicoatings on both surfaces. Generally these will reduce reflections and increase transmission of the light passing through with fewer possible changes in clarity or color change. Super multicoated ones go a level better but again, you or others may not notice. Also, unless you are using a super wide angle or stacking filters, don't bother buying the 'slim' versions. Again, extra cost if you don't need those versions.
Generally, all the major manufacturers will use better optical glass that is ground and polished flat to prevent distortions. SO unless you get a no-name brand, you will do OK with the manufacturers you mentioned.
For me, I am really happy with the Hoya multicoated ones. Not too expensive and do what I want them to do.
Hope this helps some.

The square filter system is useful if you use lots of filters. You simply slide one out and replace it. With screw-in filters you have to keep unscrewing the little blighters!
To be honest, with digital, I only use neutral density (not graduated) and a circular polariser. Anything else can be done with Photoshop.

who me? is right, make sure that you get multi-coated filters. I use Hoya, they're relatively cheap and good quality.

While I really don't care for using filters, at the times when one is called for I use B+W or Heliopan only. My thinking? The glass making process is better (the lens is cut from a large block of glass rather than being pored into a mold) and, (and this is a big 'and' for me) the rings are made of brass and don't seiz as do the ones made of aluminum.

I read about the brass vs. aluminium thing in another thread somewhere. Is there also less light loss with the more expensive or thinner filters? I am mostly interested in circular polarizing right now and I hate to loose those f stops I paid double the price to get.

I have always used aluminium, and never had a problem with jammed filters.

I'm very happy with Hoya, but it is really down to personal preference.

There is some variance between different circular polarisers, in terms of loss of light. I read somewhere (can't remember where!) that light loss can vary between 1 1/3 and 2 stops.

Glass thickness, in general, won't have a noticeable impact on transmissivity. Polarizers aren't all made with exactly the same technology (or effectiveness), which will account for the differences in filter factors there.

Just bought an bunch of Hoya filters - thanks all - you were all very helpful.

Isn't there an issue concerning difference in meal here, brass and aluminum??? Like different rate of expansion!!!???