Lunt Double Stack Filter For 80mm & 100mm Universal Telescopes
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Lunt Double Stack Filter For 80mm & 100mm Universal Telescopes - SFPT
The SFPT is the internal double-stack module for Lunt's 80mm and 100mm Universal Modular Telescopes. It adds a second precision etalon inside the telescope body, reducing combined system bandpass from 0.45Å single-stack to <0.28Å — without altering the telescope's external dimensions, balance, or night-sky capability.
The improvement in chromospheric contrast at <0.28Å is immediate and significant. Surface detail that single-stack views render as texture separates into discrete structure. Plage boundaries sharpen into defined cellular networks.
Filaments reveal dark cores and complex multi-strand architecture. Active regions display the full depth of their magnetic complexity. Prominences show internal threading and flow patterns that single-stack instruments at this aperture simply cannot resolve.
The SFPT 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. The module includes dual independent Doppler True tuning knobs — one for each etalon — allowing precise independent control of bandpass position for optimum contrast on any target.
Features:
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Internal Double-Stack Module: Designed for Lunt LS80MT and LS100MT Universal Telescopes, the SFPT adds a second precision etalon inside the telescope body.
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Ultra-Narrow <0.28Å Bandpass: Combines the SFPT's 0.4Å etalon with the telescope's 0.45Å internal etalon to achieve a combined system bandpass of <0.28Å.
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Enhanced Chromospheric Detail: Reveals finer solar surface structure, with improved definition in plage, filaments, active regions, and prominences.
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Dual Independent Doppler True Tuning: Features separate Barometric pressure tuning controls for each etalon, allowing precise independent adjustment for optimum contrast.
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Customer-Installed Design: The SFPT can be installed by the customer without requiring the telescope to be returned to the factory.
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Flexible Upgrade Option: Add the SFPT when purchasing a new telescope or upgrade an existing compatible LS80MT or LS100MT at any time.
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No Impact on Night-Sky Configuration: The internal double-stack module does not alter the telescope's external dimensions, balance, or night-sky capability.
What's Included:
✓ Lunt Double Stack Filter Unit
✓ Pressure Tuner
✓ Case
✓ Instructional Manual
Specifications:
|
Model |
SFPT — Internal Double Stack Module |
|
Compatible With |
LS80MT Universal Telescope | LS100MT Universal Telescope |
|
Single Stack Bandpass |
0.45Å (telescope internal etalon) |
|
Module Etalon Bandpass |
0.4Å — individually verified |
|
DS Combined Bandpass |
<0.28Å — SFPT (0.4Å) + MT internal PT (0.45Å) |
|
Tuning |
Dual 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 |