The 18" is unlike anything we've ever done in previous dobsonians. The entire structure is metal, using a skeletal like design to save on weight (full telescope is 150 pounds including optics). The primary mirror is a cellular sandwich design providing fast cooling and light weight, only 20 pounds! The primary is 2" in thickness and has a focal ratio of f/4.12 producing a low eyepiece height!
The telescope will be on display both days. Please remember this is still a prototype. We will be looking for feed back both good and bad. We want to know what you think so we can further the design to provide the first affordable 18" dobsonian!