Baader Cool-Ceramic Safety Herschel Prism Mark II 2" Visual

2" wedge-type Herschel prism with Cool-Ceramic technology, single-sided Phantom Group® coating, ceramic Solar Finder, ClickLock® 2" eyepiece holder and integrated rotation mechanism for polarizing filters — the ultimate tool for visual solar observation in unfiltered white light. Version Visual Mark II.

Space technology applied to safe solar observation

The Baader Herschel Prism Cool-Ceramic Safety Mark II is the absolute reference instrument for visual solar observation with refractors. The principle of the Herschel prism is straightforward: instead of filtering sunlight in front of the objective, it uses only 4.6% of the incident light reflected from the first surface of the prism for observation, diverting the remaining 95.4% — the high-intensity thermal energy — into the internal light trap system. The 4.6% transmission is further reduced by a factor of 1000 by the ND 3.0 filter included as standard, bringing the light reaching the eye to completely safe levels.

The Cool-Ceramic technology represents the evolution of the light trap system: a multi-layer structure of thermal screens and heat-absorbing ceramic — the same technology as the thermal tiles of the Space Shuttle — absorbs radiant heat without overheating the surrounding environment. The prism remains thermally stable even after extended sessions. The fully enclosed housing eliminates any risk of glare or fire from emitted solar light: observation with this instrument is safe for private individuals, public institutions and schools without the need for any additional front solar filter.

Mark II: integrated rotation mechanism for polarizing filters

The main innovation of the Mark II over previous versions is the integrated rotation mechanism for polarizing filters. Since the Herschel prism naturally emits single polarized light, combining this mechanism with the Baader Single Polarizing Filter 2" (#2408342, optional) and the included ND filter provides continuous stepless brightness adjustment — the optimal method for adapting solar contrast to the observer's preferences and seeing variations. All filters remain in the prism even during eyepiece changes: there is no need to refit them each time.

The Visual Mark II version includes the new Baader Solar Continuum Filter 2" 7.5nm (540nm) #2961581, which isolates the optimal spectral window for viewing solar details in green light, significantly improving the contrast of granulations, sunspots and faculae structure compared to pure white light observation.

Ceramic Solar Finder, ClickLock and S58 dovetail

The ceramic plate integrated into the prism body simultaneously acts as a heat trap and as a Solar Finder: sunlight passing through the prism body forms a bright spot on the ceramic, allowing the telescope to be aimed at the Sun without looking through the eyepiece — simple and safe. The ClickLock® 2" eyepiece holder locks any eyepiece with just 15° of rotation, without side screws that could cause mechanical stress — even with winter gloves. The S58 dovetail attachment system with safety grooves on the 2" bayonet and the new factory-preset 3-point adjustment system complete a mechanically professional build.

⚠️ Warning: The Herschel prism can be used exclusively with refracting telescopes. It is not compatible with reflecting telescopes (Newtonian, Cassegrain, Dobsonian) or systems with lenses in the focus zone. For refractors up to 8" aperture, tested by Baader for visual safety.