Originally posted by VoiceOfReason I'd really like something like the 18-250 in a weather sealed setup, ...
While the Tamron/DA18-250mm is not wether-sealed, it is a very sturdy and robust lens. One needs to remember that the Tamron/Da18-250mm was developed and sold when weather-resistance was not yet a marketing ploy.
Many PF members and others have used the lens in atrocious conditions. I am one such person: I shoot in foul weather incl. subtropicl storms, floods, in mud, near seawater splash .... Although I do take care of my DA18-250mm, I genuinely believe that it is well suited for foul weather conditions.
The only down side is the zoom action: I always clean carefully the extended lens before I retract the zoom.
Simply if you think that the Tamron/DA18-250mm is the right lens for you, it will serve you well in poor weather conditions as long as you take care of it.
Hope that the comment may help...