Optolong OIII 18nm Filter
| Article number: | OIII-18-1 |
| Availability: | In stock |
| Delivery time: | In Stock! |
OPTOLONG 1.25" 18nm O-III Filter for Telescope 1.25 inch or 2 Inch Eyepiece Cuts Light Pollution
Feature:
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
90% transmission at 495.9nm and 500.7nm
0.1% transmission Hg at 435nm and 578nm
0.1% transmission Na at 589nm
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