Post by SuperDeluxe on Apr 12, 2013 16:38:42 GMT -5
An old Mamiya SL39 (UV) filter has just fallen on my lap. It looks in really good condition so I thought it'd be a good idea to use it on one of my Nikon lenses for protection (this particular Nikon lens seems to be a magnet for dust).
Issue is, after placing the filter on a white surface I realized that it has a subtle yellowish cast. Is this how this filter is supposed to be, or maybe age has degraded the glass? I've used my fair share of UV filters in the past (from Kenko to B&W) and don't remember any of them having a colour cast.
Sorry if this is an ignorant question, and thanks for the help.
That's quite noticeable within the shots, surprising degree, but if on digital just re-set white balance with the filter on, or adjust in Photoshop. Some glass does age yellow, Russian glass does and some Leica from long ago. Mamiya would have made the glass filters themselves, and they should be top quality.
I'm certainly not an expert on filters, but I remember the 'skylight' filters, which were often sold as UV-filters and they did have a positive yellowish hue (however weak). Does that ring a bell, or am I completely off topic? Hans
The Skylight Ia and 1B are a very pale salmon colour, resulting in a warmer tone, which say for distant mountain views removed excess blueness on colour slide film, the effect was often far too subtle for most colour print film. The yellowing here is definitely age effects on the glass and coating.
All filters stop UV anyway, and most UV is lost by the glass elements in the lens, especially in modern zooms with MC. The average UV filter will only improve a three or four element older single coated lens or an un-coated lens. UV getting through only affected colour film, not black an white, and caused a mild blue tinge, which the Skylight salmon remove even more strongly.
Skylight filters were popular with German Agfa colour slide, as it had a tendency to blueness, and the use with early Kodachrome gave a slight over warming salmon cast, but worked well with Ektachrome.