Optolong CF (Clear Focusing) Broadband Filter 1.25"/2" Mounted (OPT-CF-125/OPT-CF-2)
Optolong CF (Clear Focusing) Broadband Filter 1.25"/2" Mounted (OPT-CF-125/OPT-CF-2)
Filter Size
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Product Description
Optolong Clear focusing filter is designed to highly pass the visible spectral region 420-680nm at 98.5% transmission.
Main Use
- Use of astrophotography filters, especially narrowband filters, often results in dim images which can be difficult to focus. Clear focusing filter can be used first to clearly focus the image.
- Use with modified DSLRs for higher efficiency and sensitivity by passing visible range with 98.5% transmission.
- Act as an outstanding dust shield, which prevents the possibility of dust settling on the lens during long time exposure.
WARNING: The filters of Optolong are not designed for sun observation. DO NOT LOOK AT THE SUN WITH OPTOLONG FILTER. You would be BLIND if you fail to observe the warning.
What's in the Box
Specifications
Clear Focusing Filter Spectrum and Characteristic
- Substrate: B270
- Thickness: 1.85mm
- Tave: T>98.5%
- Surface quality: 60/40
- Transmitted Wavefront RMS: λ/4
- Parallelism: 30s
Coating Technology
- Multi-layers anti-reflection coating
- Non-cementing optical substrate coating
- Optolong L-Pro filter adopts precision coating based on Ion-assisted deposition coating technology for durability and resistance to scratching, as well as stability on CWL(central wavelength) no deviation affected by temperature change.
- Planetary rotation system offers precision and homogeneity of coatings ensuring high value on transmission of pass-band and Optical density of off-band.
Additional Articles, Videos, and Links
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Astrophotography for Beginners Step 2: How to Shoot the Moon
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