LUNT B3400 Blocking-Filter in 2 inch extension tube

50mm H-alpha double-stack solar filter, for all LS50FHa filter-systems and LS60THa/LS60MT telescopes.This double-stack Etalon is compatible to all Lunt Solar Systems LS50FHa filter-systems and LS60THa / LS60MT telescopes. Adding this additional double-stack Etalon system will reduce the bandwidth to ~<0.55 Angstrom (dependent upon used telescope). So you will have much more contrast and more details on the sun will be visible.Without blocking filter! Only for use as double-stack filter, or together with a additional available blocking filter. If the filter is used only single stacked together with a optional blocking filter, then the bandwidth is <0.75 Angstrom.FEATURESAperture: 50 mmNo central obstructionBandwidth double stacked: <0,55 AngstromTuning: tiltable EtalonHousing diameter: 95 mmLength: 73 mmWeight: 0.7 kgFront thread: M90x1 female threadRear thread: M90x1 male threadSCOPE OF DELIVERYLS50FHa solar filterTransport caseInstruction manual

​Modular designed multipurpose telescope, both for observing the sun in the H-alpha wavelength, as well as for night sky observations. Easy conversion between the different applications with a few simple steps. 2-lens ED Apo telescope with FPL-53 glass, 80mm aperture and 560mm focal length - very good image quality for H-Alpha solar observation and also for observing the starry sky at night.With innovative air pressure tuning system and good 2 inch (50.8mm) R&P focuser. Delivered without blocking filter, use for H-Alpha sun observation only possible with additional blocking filter!This telescope is supplied without blocking filter. We offer a wide range of additionally available blocking filters in different sizes, either mounted in a 90° star-diagonal housing or in a straight extension tube. These are all usable with this telescope.ATTENTION: Without such an additional blocking filter you cannot use this telescope for H-alpha solar observation!Solar observing in H-alpha:The LS80MT is a telescope for observing the sun in H-alpha light, with 80mm free aperture (no central obstruction) and 560mm focal length. The H-alpha wavelength is the most impressive way to observe the sun, showing protuberances at the sun's edge, filaments and flares on the surface, and much more. An internal Etalon filter achieves a bandwidth of <0.7 Angstrom with the innovative air pressure tuning system Pressure-Tuner. Tuning is done by slightly changing the air pressure in a pressure chamber inside the telescope. This changes the refractive index of the air, making it easy to tune to the H-alpha line. The pressure tuner guarantees a homogeneous image, without central obstruction, and a permanently protected Etalon without erosion. A set of collimating lenses installed in the telescope ensures best performance.Fine adjustment is achieved with a solid 2 inch R&P focuser with 10:1 reduction.This version of the LS80MT is delivered without blocking filter. Therefore an additional blocking filter is required to use the telescope for solar observation in the H-alpha wavelength. You can choose from the wide range of Lunt Solar Systems blocking filters and decide for example if you want a blocking filter in a 90° star-diagonal housing or one in a straight extension tube.Observing the starry night sky:The H-Alpha Etalon system can be removed from the telescope in a few easy steps thanks to its modular design. With the additionally available conversion kit (item number 0551330) the 2-lens ED Apo refractor can then be used as a normal telescope with 80mm aperture and 560mm focal length for observation and photography of the night sky. The FPL-53 doublet lens offers an low colour aberration image. Common 2 inch star diagonals can be used at the high quality R&P focuser of the conversion kit 0551330.Please note that the optionally available conversion kit 0551330 is absolutely necessary if the telescope should be used at night.More applications:With additionally available accessories the LS80MT offers even more possibilities!- Double-StackThe LS80MT telescope can optionally be upgraded with the additionally available double-stack module DSII/SFPT (item number 0551395). The DSII system is a internal double-stack module. Thereby a bandwidth of <0.5 Angstrom is achieved for H-alpha solar observation. Therefore much more details on the solar surface will become visible.- Solar observing in White-LightIf the H-alpha unit has been removed, of course either a sun filter to be installed in front of the objective, or a Herschel-wedge at the focuser can be used to observe the sunspots in White-Light.- Solar observing in Ca-K wavelengthCertainly, the Ca-K filter modules from Lunt Solar Systems can also be used at the LS80MT to observe and photograph super-granulation and other effects visible in this wavelength on the sun.This makes the LS80MT a completely universal usable ED Apo telescope of very good quality!FEATURES2-lens ED APO refractor, FPL-53Aperture: 80mm (no central obstruction)Focal length: 560mmBandwidth: internal Etalon with <0.7 AngstromTuning: air pressure tuning system Pressure-TunerSupplied without blocking filter, additionally available blocking filter absolutely necessary!Focuser: R&P with 10:1 reductionTwo tube-ring with handleSol-Searcher installed inside handleDovetail bar at GP-level for astronomical mountsWeight: 4.95kgLength with blocking filter and dew-shield: 62cmLength without blocking filter and removed dew-shield: 50cmSCOPE OF DELIVERYLS80MT Multipurpose TelescopePressure-Tuner2 inch R&P focuser with 10:1 reductionTube rings with dovetail bar and sol-searcherTransport case (78x33x23cm)Instruction manualConversion kit for observation of the starry night sky (0551330) not included!