You asked
Is the voigtl nder heliar 40mm f 2 8 aspherical weather sealed?
Here is what the site says about that.
From Voigtländer Heliar 40mm f/2.8 Aspherical: Voigtländer Heliar 40mm f/2.8 Aspherical: A prime lens by Voigtländer for Full frame cameras, 40mm f/2.8. Specs - Maker: Voigtländer - Focal length: 40mm (prime) - Maximum aperture: f/2.8 - Made for: Full frame sensors - Mounts: Leica M - Stabilised: no - Autofocus: no, manual focus What it frames like - On full frame (Leica M): as marked, 40mm. Cameras it fits - Leica M9: Full frame - Leica M9-P: Full frame - [Leica ...
From Landscape: What matters: - Resolution and dynamic range. Landscapes are often printed big and include bright skies and dark foregrounds in one frame. A sensor with a lot of dynamic range keeps detail in both. Full-frame and high-resolution bodies shine here, but any modern sensor does well at base ISO. - Weather sealing. You'll be out in wind, spray and drizzle at dawn. A sealed body and lens survive it. - A tilting ...
Quoted from this site's pages.