Optolong SHO Filter Set 3nm 2" (H-alpha/O-III/S-II)
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Vai al moduloThe Optolong SHO Filter Set 3nm 2" (H-alpha / O-III / S-II) is the even narrower-band version of the Optolong SHO range, designed for the maximum possible contrast with cooled monochrome CCD cameras and modified DSLRs.
Three filters, extra-narrow bandwidth
The set includes an H-alpha filter (656nm, 3nm bandwidth), an O-III filter (500nm, 3nm bandwidth) and an S-II filter (672nm, 3nm bandwidth). Corresponding to the R-G-B channels (H-alpha, O-III, S-II), they allow processing of images in "Hubble" style with astronomical post-processing software. Compared to the 6.5/7nm version, the narrower bandwidth provides greater contrast, reduces background noise, and increases the visibility of faint nebula signals.
Construction and coatings
The filters are made with high-quality optical substrate and multi-layer coating using ion-assisted deposition (IAD) technology, which ensures scratch resistance and central wavelength stability even with temperature changes. The frame is aluminum.
Technical specifications
| Parameter | Value |
|---|---|
| Filters included | H-alpha, O-III, S-II |
| Bandwidth | 3 nm |
| Format | 2" (50.8mm) |
| Frame | Aluminum |
| Brand | Optolong |
Who it's for
Ideal for astrophotographers using cooled monochrome CCD cameras or modified DSLRs who want the maximum contrast available for false-color images in the "Hubble Palette" style of emission nebulae, planetary nebulae, and supernova remnants, with reduced background noise and increased signal from faint nebulae.