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Antlia 3nm Narrowband OIII Pro Filter

by Antlia
Original price $344.00 - Original price $661.00
Original price
$344.00 - $661.00
Current price $344.00
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Antlia OIII Pro narrowband filter optimizes the FWHM (full width half maximum) to 3nmbandpass. As the bandwidth becomes narrower, the 3nm Pro narrowband filters enhance contrast of emission targets by lowering the unwanted background signal. Antlia OIII 3nm Pro filtersare designed to deliver 85% transmission at the 500.7nm line which provides you with the maximum signal and well defined nebulae structures.

Conventional broader narrowband filters cause a heavy loss in transmission due to the strong Center Wavelength (CWL)shift. We guarantee T>85% within 1nm range of the center bandwidth, which means that the 3nm Pro narrowband filter can guarantee high transmittance for working with both long focal ratios and fast optical systems. Blueshift data shows that Antlia 3nm Pro filters can be used with nearly all systems as fast as f/3 with minimalloss in emission signal and meets the requirements of fast optics like Hyperstar and RASA.

The out of band blocking specification is rated OD5 (0.001%) which delivers an excellent SNR(signal to noise ratio) and effective cutoff rate to minimize interference from other wavelengths.Improved sharp cutoff astrophotography 3nm Pro filters are designed to minimize halos around bright stars.

Application and Performance:

High transmittance and smallest bandwidth to maximize contrast

Steep spectral profile minimizes halos around bright stars

A single substrate to eliminate internal reflections

Narrowband Objects: OIII Emission Nebulae, Planetary, Wolf Rayet Nebulae and Supernova Remnants

Use in light polluted areas and dark sites

Extendsimaging time when the moon is up

Antlia narrowband Pro filters can be used down to F/3 systems with slight loss of signal

All Antlia Narrowband filters are edge blackened to eliminate internal reflections from stray light

Superior optical reliability reduces post image processing

This filter is not suited to deep sky objects that do not contain OIII emissions.

Technical Specifications:

Basic Substrate: optical substrate

Filter Thickness: 2mm+/-0.05mm for 2'' mounted

FWHM (Full width at half maximum): 3nm

CWL (Central Wavelength): 500.7nm

Peak Transmission: >85%

Blocking: > 5 OD(0.001% out of band blocking) @ 300-1000nm

Surface Quality: S/D (scratch/dig)= 60/40 (Refer to MIL-O-13830)

Transmitted Wavefront: Lambda/4 or better.

Parallelism: less than 30 arcsec

Single / Non-glued substrate

Warranty: 3-years against delamination