I am thinking of buying a series 9 set of filters (because smaller filters cut off the image circle). Only Tiffens are readily available. I have heard that laminated filters fade with age or in the sunlight and that solid-glass filters will not fade. Has anyone had a problem with laminated filters fading?

-- William Marderness (wmarderness@hotmail.com), June 06, 2000

Answers

All dyed filters will fade with light and time, whether the dye is in a gel or in glass.

Chances are that you won't have any fading problems for many years. A big drawback of laminated filters, though, is that they'll separate.

An good alternative to Series 9 filters may be the Calumet/Lee filter system.

-- John Hicks (jbh@magicnet.net), June 06, 2000.

My experience is the same as John's. How much a given filter fades is determined by what part of the spectrum the dye absorbs. No need to go into the chemistry here. Having said that, I still have some 40 y old filters that work fine [both kinds]. Probably not the same as when they were new, but still do the job. I've found scratching to be a bigger worry.

Best wishes,,,

-- Z1X4Y7 (Z1X4Y7@aol.com), June 06, 2000.

Hoya claims that their filters will not fade, unlike laminated filters. I wonder if this is true. The following is from Hoya's website:

Over time the expansion and contraction of the different materials can lead to de-lamination, which is a separation of the different materials. This will show up as bubbling, pealing, or discoloration, rendering the filter useless. The color of the gel can shift or fade over a relatively short period of time. If all six surfaces, three layers, two surfaces each, are not perfectly flat and perfectly parallel, the filter causes a lens effect which degrades the optical performance, or in extreme cases, shift or limit the focus of the lens it is used with.

To make colored filters, Hoya adds different raw elements, like gold, and chemicals to its optical glass while it is in a molten state. This insures that Hoya filter glass is uniformly colored all the way through. There is never any risk of uneven coloration, shifting or fading of the color, or delamination. The two surfaces are ground and polished for perfect flatness.

-- William Marderness (wmarderness@hotmail.com), June 06, 2000.

Solid glass filters like Heliopan's can not fade as the color is determined by the minerals used in the raw glass mix.

gel filters sandwiched between glass will fade.

Filters laminated with colored glue probably do not fade.

-- Bob Salomon (bobsalomon@mindspring.com), June 06, 2000.

Bob:

Speaking as someone who has a PhD in chemistry, I can confirm that your statement can't be supported. Even so, It matches my experience.

Best wishes,,,,

Z

-- Z1X4Y7 (Z1X4Y7@aol.com), June 06, 2000.