The iOptron Photron 254mm f/8 Ritchey-Chretien Catadioptric Truss-Tube Telescope builds on the success of the solid tube models in the series with a completely redesigned housing that utilizes an open truss system to improve the overall thermal dynamics that allow the optical system to settle into the ambient temperature faster and resist heating up better than traditional closed steel tubes. The carbon fiber tubes are also thermally stable so they won't expand and contract like metal does, ensuring accurate alignment throughout the night and throughout the year.