To view DWF images use theWHIP! browser plug-in:
Once you add WHIP! capability, you won't have to do it again unless you want or need a later version. The effort to get and install this plug-in is well worth it to see all the detail DWF format offers.
DWF (Drawing Web Format) is file format proposed as a standard by Autodesk for making AutoCAD drawings available on the web. DWF files are optimized for web viewing. As a vector format, DWF files have the big advantage of allowing panning and zooming. They are smaller than DWG files, can contain URL links, and allow images to be distributed while keeping the DWG files proprietary.
Remember to access WHIP! pan and zoom features using the right mouse button!