The differences are
a. Colour cast-- expensive ones are truly neutral, will not introduce unwanted colour cast (eg ND filters)
b. Quality-- use of brass rings instead of aluminium, less chance of seizing up (and have to use filter wrench to remove)
c. Flare resistance-- the good ones (ie multicoated) will not cause flare.
d. Light transmission-- the good ones pass through more light than the inferior ones.
e. Durability-- good ones are made of glass which resist dirt and are easier to clean if dirty. Lousy ones are made of plastic, very difficult to keep clean. Hoya has this problem even for their HMC filters.
f. Scratch resistance-- good ones have strong coatings
g. Resale value-- good filters have good resale value, lousy ones have lousy resale value.
All the above said, be sure what you are using a filter for. With PS and digital, almost any effect can be simulated/created in PS, so there's practically no need for filters which rob sharpness and suck light. The only filters a digital user really needs are (i) polarizer (ii) IR (if you want to shoot IR) and (iii) ND8 (if you really want to open your shutter for a long time). Everything else, from 80A to 85C, K2 to O(G) can be simulated in PS.
Wai Leong
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di0nysus said:
I've tried googling and search CS, not much answers,
what differences are they between B+W and other brands, multi-coat vs non multi-coat etc... price can differ many folds!
experts please share! Thanks