Photoclubalpha

I got this one with the Film 7 and grip I picked up for a song.
Sadly the lens was "foggy"
Bit like the Marumi soft focus filter I have, at all apertures and focal lengths

I pulled apart the lens and the rear element was very odd looking and fogged.
I've read a few ho hum reviews of the lens, I couldn't actually say if the lens is any good or not due to the soft focus effect!

This lens went into the bin!

I have a Tokina AT-X 400mm f5.6 that I bought new in 1992. In 2005 when I got my KM 7D I pulled it out of the closet and discovered that inside there was a fogged element. Turns out it wasn't fog or fungus. The last time I had looked at the lens a few years before it was fine though. I asked about it here and got some good responses:

http://photo.net/filters-bags-tripods-a ... rum/00BTJ2

Maybe your Sigma has the same problem.