In the nebula filters category you will find both broadband and line filters. The latter only selectively allow the light of a certain spectral line through. OIII and H alpha filters are especially popular. Many deep sky objects will only reveal their full glory when observing using these filters!
As the name suggests, wideband and narrowband filters pass a wider range and narrower of the spectrum. They are used primarily to suppress light pollution.

Omegon
Filters Nebula/ city light filter 1.25 ''
( 3.5 / 5 )
$ 39.90
ready for shipping in 24
h

Omegon
Filters Pro 1.25'' UHC filter
$ 69.00
ready for shipping in 24
h

Optolong
Filters L-Quad Enhance 2"
RRP:
$ 279.00
Our price:
$ 267.00
ready for shipping in 24
h

Optolong
Filters L-eXtreme 2"
$ 384.00
ready for shipping in 24
h

Optolong
Filters L-Pro 2''
( 5 / 5 )
RRP:
$ 244.00
RRP:
$ 244.00
Our price:
$ 232.00
ready for shipping in 24
h

Omegon
Filters Pro 2'' UHC filter
$ 99.00
ready for shipping in 24
h

Omegon
Filters Light Pollution Filter, 2”
( 3.33 / 5 )
$ 59.00
ready for shipping in 24
h

Optolong
Filters L-eNhance 2"
( 5 / 5 )
$ 279.00
ready for shipping in 24
h

Optolong
Filters L-Ultimate 2"
$ 465.00
ready for shipping in 24
h

Omegon
Filters 1.25'' deep sky filter
$ 89.00
ready for shipping in 24
h

Optolong
Filters L-Pro 1.25''
RRP:
$ 186.00
Our price:
$ 174.00
ready for shipping in 24
h

Omegon
Filters OIII filter 1.25''
$ 89.00
ready for shipping in 24
h

Celestron
Filters CLS RASA Origin
$ 395.00
ready for shipping in 1-2
weeks

Omegon
Filters Pro Nebula CLS Deep Sky Filter 1,25''
$ 69.00
ready for shipping in 24
h

Optolong
Filters L-eNhance 1.25
RRP:
$ 221.00
Our price:
$ 209.00
ready for shipping in 24
h

Optolong
Filters L-eNhance APS-C EOS Clip
( 3.5 / 5 )
$ 314.00
ready for shipping in 24
h

Astronomik
Filters UHC 1.25"
$ 116.00
ready for shipping in 24
h

Omegon
Filters OIII Filter 2"
( 5 / 5 )
$ 119.00
ready for shipping in 6-10
weeks

Optolong
Filters L-Para 2"
$ 349.00
ready for shipping in 24
h

Omegon
Filters Pro UHC filter M56
( 1 / 5 )
$ 99.00
ready for shipping in 24
h

Optolong
Filters L-Pro Filter 77mm
RRP:
$ 419.00
Our price:
$ 335.00
ready for shipping in 24
h

Omegon
Filters Pro 2'' CLS filter
$ 99.00
ready for shipping in 24
h

Optolong
Filters L-Pro Canon EOS R Clip
RRP:
$ 349.00
Our price:
$ 279.00
ready for shipping in 24
h

Optolong
Filters L-Pro Clip Sony Full Frame V2
$ 279.00
ready for shipping in 24
h

Optolong
Filters L-eXtreme 1,25"
$ 291.00
ready for shipping in 24
h

Astronomik
Filters 1.25" OIII filter
$ 116.00
ready for shipping in 24
h

Omegon
Filters 1.25'' Clear Sky filter
$ 129.00
ready for shipping in 24
h

Optolong
Filters SII Filter 2"
RRP:
$ 279.00
Our price:
$ 267.00
ready for shipping in 24
h

Vaonis
Filters Dual Band VESPERA
$ 465.00
ready for shipping in 24
h

Vaonis
Filters CLS VESPERA
$ 267.00
ready for shipping in 24
h

ZWO
Filters 1.25" Duo band
RRP:
$ 151.00
Our price:
$ 134.00
ready for shipping in 24
h

Astronomik
Filters UHC 2"
$ 232.00
ready for shipping in 24
h

Optolong
Filters L-Ultimate 1,25"
$ 302.00
ready for shipping in 24
h

ZWO
Filters 1.25" filter set: H-alpha, SII, OIII
RRP:
$ 670.00
Our price:
$ 548.00
ready for shipping in 24
h

Astronomik
Filters H-alpha 12nm CCD Clip-Filter Sony alpha
$ 395.00
ready for shipping in 24
h

Baader
Filters H-alpha/OIII/SII CMOS Narrowband 2"
$ 770.00
ready for shipping in 1-2
weeks