Double Stack Filter for Lunt 130mm Telescope

LFPT — Internal Double Stack Module For Lunt LS130MT & LS152 Telescopes. Now with new-generation etalons — every unit individually tested on Lunt's precision metrology equipment. Every specification is verified, not estimated. The LFPT is the internal double-stack module for Lunt's 130mm and 152mm telescopes — the DS upgrade for the largest instruments in the Lunt modular range. It adds a second precision etalon to the internal optical path, reducing combined system bandpass to <0.28Å and delivering the highest contrast H-alpha performance available in any Lunt modular telescope. At 130mm or 152mm aperture with <0.28Å combined bandpass, the level of chromospheric detail revealed is exceptional. Individual intergranular network elements become resolvable. Active region magnetic architecture shows complexity not visible in smaller or single-stack systems. Plage structure reveals fine internal organisation — bright knots and threads of concentrated magnetic field within the broader active region. Prominence dynamics can be studied in real time with genuine scientific detail. At this aperture and bandpass, the chromosphere becomes a research instrument as much as an observing experience. The LFPT is designed for customer installation — no factory return required. It can be purchased at the time of telescope acquisition or at any point thereafter, making the DS upgrade a genuine deferred investment rather than a permanent commitment at point of sale. Once installed, the module does not affect the telescope's night-sky configuration — remove the solar module and the instrument performs exactly as it did before. Specifications Model: LFPT — Internal Double Stack Module Compatible With: LS130MT Modular Telescope Single Stack Bandpass: 0.45Å (telescope internal etalon) Module Etalon Bandpass: 0.35Å — individually verified DS Combined Bandpass: <0.28Å — LFPT (0.35Å) + MT internal PT (0.45Å) Tuning: Independent Doppler True Barometric pressure tuning Installation: Customer-installed — no factory return required Night Sky Use: No impact — internal module does not affect night configuration