IDAS 2" NBZ-II 10nm Ha & 8nm OIII Dual Band Filter

IDAS 2" NBZ-II 10nm Ha & 8nm OIII Dual Band Filter

The IDAS NBZ-II is a new dual band nebula booster filter - the successor to the NBZ (NBZex) filter. The FWHM of the NBZ-II is 8nm (+/=0.4nm) at OIII, and 10nm (+/-0.4nm) at H-alpha respectively. This has the same anti-Haloing characteristics as the NBZ did. A test report of the actually measured optical properties is provided with each individual NBZ-II filter piece shipped.

The transmittance curve of interference filters will naturally shift towards the shorter wave length side against oblique light incidence, and this tendency will be more noticeable as the inncidence angle becomes higher as shown in the 3rd photo above.

Some of the competitive 7nm or narrower filters will decrease in transmittance by 50% or more when used in a fast optical system (around F2), while the NBZ=II retains 80% or more of the transmittance under the same conditions.

The shift tendency will be stronger in optical systems that have a central obstruction. Taking this into consideration, we have designed the NBZ-II as you can see from the simulation in the 4th photo above.

Technical Specifications

• 2" mounted; M48mm x 0.75mm
• Glass thickness: 2.0mm

In the Box

• NBZ II Filter
• Individual spectrographic test report

Manual & Warranty

IDAS 3-Year Warranty