ANTLIA H-BETA & OIII VISUAL FILTER 1.25"
Antlia
ANTLIA H-BETA & OIII VISUAL FILTER 1.25" is backordered and will ship as soon as it is back in stock.
The Antlia H-Beta and OIII filter is designed for visual observation of emission & planetary nebulae and supernova remnants under light polluted skies. It has >90% transmission at both OIII 500.7nm & 495.9nm and H-Beta at 486.1nm. The optical density of OD4 suppresses unwanted wavelengths from light pollution, moonlight and skyglow, resulting in excellent contrast. It can also be used for photography with colour cameras and cuts out both the UV and IR ends of the spectrum.
To even further enhance the contrast, and suppress the stray light and internal reflections, Antlia applies edge-blackening coating on each filter. Each filter is individually tested to ensure a high quality standard. The tight tolerance of the filters substrate assure a maximum deviance of ±0.05 from specifications making these filters parfocal.
DO NOT LOOK AT THE SUN WITH ANTLIA FILTERS. Serious eye damage will occur.
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Specifications
Passing band | H-b, OIII |
Glass thickness |
2.0 mm ±0.05 |
Optical flatness |
1/4 λ (wavefront) |
Bandpass transmission | >90% |
Off-band transmission | OD4 @ 300-1000 nm |
Coating | Double-sided multilayer nano-coating |
Surface quality | 60/40 (in accordance with US military watch MIL-O-13830) |
Parallelism | 30" |
SKU |
AN-HB-OIII1.25 |
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Bandpass (FWHM)20 nm
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Glass thickness2 mm
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Filter size1.25"