IDAS NB3 Dual Band Narrow Nebula Filter O-III, S-II - 2 inch mounted

IDAS NB filters from Hutech are specially designed for astrophotography

The NB3 filter is a dual line pass filter that can be used with one-shot color (OSC) cameras such as DSLRs, mirrorless system cameras or astronomical cameras.

The NB3 filter lets the red SII lines and the blue-green OIII lines through and increases contrast. It is an addition to the NB2 nebula filter and enables false-color images and narrow-band nebula images.

{{The main features of the IDAS NB3 nebula filter:}]

Allows for about 4x increase in exposure time

Lets O-III and S-II pass

Passbands slightly extended to longer wavelengths for still allowing the lines to pass in case of oblique incidence due to large angles, making the filter suitable for very fast optics

Suitability for narrow-band imaging of diffuse emission nebulae and planetary nebulae

High-quality anti-reflection coating

Especially scratch-resistant hard coating

Absorption of the urban scattered light (mercury, sodium vapor lamps, ...) and the nightglow

Exposure time extension - factor 4:

The IDAS NB3 allows an exposure time extension by a factor of 4, but the most important lines in the deep-sky range (S-II and O-III) are transmitted by 90%.

Put simply, you can expose about four times as long until the sky background passes through, but the object appears much stronger and more contrasty against the background than without a filter.

Difference NB1 - NB2 - NB3 Nebula Filters:

All three filters are suitable for color and monochrome cameras, DSLR and system cameras. A combination of these three filters allows extreme narrow-band images with mono and color cameras.

NB1: Triple filter with transmission at H-Beta, O-III and H-Alpha. Furthermore, the filter blocks Near IR light, no additional IR cut filter is needed. The NB1 is the most versatile filter. We also recommend the filter for astromodified DSLR and system cameras.

NB2: Dual band filter with transmission at O-III and H-alpha. The contrast effect is very strong. The filter is well suited for color astrocameras with built-in IR-cut filter and for photography with pure reflecting telescopes without corrector, such as RC telescopes.

NB3: Dual band filter with transmission at in O-III and S-II. The contrast effect is very strong. This filter is ideal for the photography of objects that radiate in the S-II range (sulfur). These nebulae often still have an O-III component.

NBZ: Dual band filter with very narrow passband of 5-6nm (ultra narrow band) in O-III and H-alpha for extreme contrast.

Astrophotographic results obtained with this filter on Astrobin

Here you can find some astrophotographs made with this filter type: Link to Astrobin

Astrophotographic results obtained with this filter on Astrobin

Here you can find some astrophotographs made with this filter type: Link to Astrobin