The Baader TZ-4S SunDancer II Telecentric System is a 4x achromatic telecentric designed for use with SunDancer H-alpha solar filters but equally covers the entire visual spectrum. This means it is not only ideal for H-alpha solar filters but can be used instead of a Barlow lens.
Telecentric systems are often used in combination with H-alpha filters for solar observation, where a perfectly parallel beam of light is critical. Unlike most other telecentric systems which are solely designed for the H-alpha wavelength, the TZ-4S can be used for all applications.
The TZ-4S illuminates a 36mm image circle at a distance of 97mm from the base of the T2 thread. Unlike simple Barlow lenses, the telecentric system gives much higher contrast and sharpness over the field, making it suitable for high magnification solar system observation even with long focal length orthoscopic eyepieces. Eye relief of the eyepieces used does not change, unlike other systems.
The telescope-side includes a dual 1.25" & 2" nosepiece with safety kerfs to prevent tilt and accidental slippage. The T2 thread on the camera/eyepiece-side allows a tilt-free connection of imaging sensors and common T2 eyepiece clamps. Additional adapter rings are available to suit almost any combination of equipment.
When used with the SunDancer II H-alpha filter, the TZ-4S replaces the original 3x telecentric, making it the perfect match for f/7-8 telescopes which will then reach the optimal focal ratio of around f/30. Note that you must remove the 12mm blocking filter from the original TZ-3S and install it onto the TZ-4S.
Note: SunDancer II H-alpha filter not included.
|H-alpha/CaK solar observation and photography, general high magnification observation
|Focal length extension
|97 mm from base of T2 thread, 70 mm when used with SunDancer II H-alpha filter
|Connection telescope side
|1.25" barrel, 2" barrel
|Connection eyepiece side
|M42 x 0.75 (T2) male thread
|BBAR (broadband anti-reflection)