Optolong Night Sky 1.25" Mounted H-Alpha Filter (IR Pass 630nm)
| Article number: | 12801 |
| Availability: | More on the Way to us |
| Delivery time: | More on the Way to Us |
The Optolong Night Sky H-Alpha filter, or IR-Pass 650nm filter, can be used for imaging of the Moon and planets as well as deep-sky h-alpha regions. This IR-Pass H-Alpha filter enhances contrast and surface detail and helps reduce the effects of seeing when used in conjunction with RGB filters for planetary imaging. It also makes a great introductory H-alpha filter.
The Night Sky H-Alpha Filter has a 50% transition from blocking to passing at about 640nm, and 95% transmission from 650nm to 1100nm.
The Optolong 1.25” Night Sky H-Alpha Filter is made with Schott glass that has been multi-coated with an ion-assisted deposition technology to ensure scratch resistance and stability on the central wavelength, or CWL. The filter cell is made of lightweight, strong metal and is CNC machined, sand-blasted, black anodized, and then laser engraved. The result is a super thin filter cell that will produce a clear aperture of 26mm.
Quality Filter Materials:
- Schott B260 substrate material from Germany, 2.0mm thick
- CNC machined and black anodized aero-metal filter cell that is ultra-thin to provide largest clear aperture; Laser-engraved to prevent fading
- Multiple layers of anti-reflection non-cementing coatings applied via electron-beam gun evaporation with Ion-assisted deposition
Optolong Filter Manufacturing Processes and Parameters
- Filter substrate is fine-optically polished to 1/4 wave and <30 parallelism over both surfaces
- Surface quality, according to MIL-O-13830, is 60/40
- 95% transmission at passband
- High value transmission of pass-band and optical density of off-band is assured through Optolong’s planetary rotation system, a homogenous and precise coating procedure
- Thin metal cells have a clear aperture of 26mm for 1.25” filters
- Each filter comes with a plastic case with high pressure EVA case lining