On Wed, 24 Aug 2005, Steve Jolly wrote:
> If you examine the filters carefully, you can see that they're slightly > concave lenses rather than plain glass. (This is most obvious if you > look at the reflection of a light source in them - you can see two > images, one bigger than the other). I found the lens very soft (on > film, at least), and have been wondering whether the filters are in fact > an important part of the lens's optics. Steve, I don't think so. The filter being necessary is apparently not mentioned in the manual, plus it's not on the optical diagram in the manual. I've not done a proper test yet (I will, I will, I promise) so I can't be certain, but most of the evidence points away. Also I can't see any concavity/convexity on the filters and they don't seem to alter the image when you look through them... Chris
