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Alpine Astronomical 100mm ASTF Baader AstroSolar 5.0 White-Light Solar Filter for Telescopes

BH #ALASTF100 • MFR #ASTF-100
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Alpine Astronomical 100mm ASTF Baader AstroSolar 5.0 White-Light Solar Filter for Telescopes
Key Features
  • Safe Solar Viewing with Nighttime OTAs
  • For Detailed, High-Magnification Viewing
  • Broad-Band Neutral-White Color
  • Optical Density of 5.0
Unlike many white-light solar filters that produce views of the sun with a red-orange, bluish, or yellow tint, the Alpine Astronomical 100mm ASTF Baader AstroSolar 5.0 White-Light Solar Filter reveals the sun in its natural white color. With an optical density of 5.0 for safe solar viewing though an optic like a telescope or spotting scope, the filter shows more surface details with greater clarity versus other types of solar filters. The filter is mounted onto a clear-white IR-rejecting plastic ring, which acts as a stabilizing element for the filter cell, and the ring is in turn mounted onto the aluminum front frame. The thermal expansion coefficient of the plastic and the film are similar to minimize thermal stress on the film for increased resistance to developing pinholes or tears.
More Details
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Safe for Solar Observation
Warning: Viewing the Sun without proper protection can cause permanent eye damage, blindness, and equipment damage. As this product meets the standards of ISO 12312-2 specifications, though certification status is not available for such items (removable filters for optics and telescopes), it is safe for solar observation through its intended optics equipment. Always use approved ISO 12312-2 certified safety glasses when viewing the Sun directly. Never use photographic neutral density filters for direct solar viewing, viewing the sun through an optic, or when using cameras with an optical viewfinder.
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Alpine Astronomical ASTF-100 Overview

Unlike many white-light solar filters that produce views of the sun with a red-orange, bluish, or yellow tint, the Alpine Astronomical 100mm ASTF Baader AstroSolar 5.0 White-Light Solar Filter reveals the sun in its natural white color. With an optical density of 5.0 for safe solar viewing though an optic like a telescope or spotting scope, the filter shows more surface details with greater clarity versus other types of solar filters. The filter is mounted onto a clear-white IR-rejecting plastic ring, which acts as a stabilizing element for the filter cell, and the ring is in turn mounted onto the aluminum front frame. The thermal expansion coefficient of the plastic and the film are similar to minimize thermal stress on the film for increased resistance to developing pinholes or tears.

With the ability to be installed on the outside or inside of an optical tube assembly, dew shield, or corrector plate retaining ring, this filter provides a safe way to view the sun through conventional nighttime telescopes. Recommended for apertures from 90-110mm, the filter is engineered with three centering bolts that can fit OTAs, dew shields or corrector plates with an outside diameter of 120-160mm, or an inside diameter of 150-190mm. Due to the shallow depth of the corrector plate on most catadioptric OTAs, for secure and safe use, Alpine Astronomical only recommends outside mounting on Cassegrain-style telescopes.

Fit
  • For the correct fit, measure the outside or inside diameter of the dew shield/lens housing - including hardware like retaining rings and screw heads - and choose the size that matches the measurement with some extra room
  • When used on Schmidt-Cassegrain, Maksutov-Cassegrain, or other catadioptric OTAs, outside mounting is required as the limited depth of the front inside diameter prevents full and secure engagement of the centering bolts
  • Recommended for 90-110mm apertures
  • 150-190mm inside diameters
  • 120-160mm outside diameter

Alpine Astronomical ASTF-100 Specs

Bandpass
White-light, broadband
Clear Aperture
100mm
Diameter
190mm
Weight
5.3 oz / 150.0 g
Packaging Info
Package Weight
0.8 lb
Box Dimensions (LxWxH)
9.4 x 8.9 x 1.3"

Alpine Astronomical ASTF-100 Reviews

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Skywatcher Evoster 100 ED. Would this size fit my ...

Skywatcher Evoster 100 ED. Would this size fit my telescope?
Asked by: Richard
Yes this Filter will work with that Model.
Answered by: Alex S
Date published: 2021-08-26

It looks like the ASFT 100 and the ASSF 80 will ...

It looks like the ASFT 100 and the ASSF 80 will both fit my telescope. The Baader film is the same in both filters. What am I getting in the ASFT 100 that warrants spending the extra $10?
Asked by: Charlie
A larger metal ring. A larger film area.
Answered by: John
Date published: 2022-09-21
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