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Baader ASTROSolar Telescope Filter (ASTF)

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Email us a question about this ProductBaader Planetarium

Baader Solar Filters provide a professional and secure solution to observe and image the Sun using AstroSolar Safety Film. 

Many ready made filters do stretch thefilter material like a drumhead in order to make it look like a piece of glass – this absolutely does destroy the image quality, rendering the film useless for high magnification work. AstroSolar must be mounted entirely stress free in order to perform like a high precision planeoptical window. It sounds like a contradiction with traditional perception of quality, but AstroSolar must show slight ripples! Only when the film is being put under stress by an improper cell mount it performs just like any single side coated glass-filter made of untreated floatglass.

All Baader Solar Filters feature:

• original Baader AstroSolar® Safety Film (OD 5.0), cell mounted and quality inspected by skilled members of our staff
• clear white IR-rejecting front ring with reinforcing raised edges along the outer and inner circumference, designed to protect the solar filter material from contact with any sharp metal edge
• 3 injection molded centering-bolts with threaded brass inserts to center the filter-cell in front of the tube opening. These bolts come in three different diameters, depending on the filter category (ASTF/ASSF/ASBF). Each bolt features injection molded rubber grip-faces, shaped to easily slide onto any telescope tube – but are very hard to come off
• no tool mounting and adjustment of the centering bolts to fit a wide variety of mechanical tube diameters. Bolts made to contact the outside or optional (if appropriate) the inside of the optical instrument tube
• non-rotating sliding fasteners made from aluminum that hold the centering bolts. These metal sliders are equipped with a machined indicator to point towards the adjustment index
• additional Phillips screws are integrated into the sliding fasteners, so that the centering bolts can be firmly fastened with a screw driver if preferred by the user
• index scale provided beside each adjustment slot – adjacent to each sliding fastener, for fast and repeatable adjustment of the filter cell onto different telescope tubes
• black sliding washers supplied to securely cover the full length of the adjustment slots in the aluminum frame
• for blocking sunlight from passing trough the filter cell beside the filter area
• (only for ASTF-filters) rubber plugs supplied as cover for closing unused adjustment slots in the aluminum frame
• three security straps included, to secure the position of the filter cell with Velcro-adhesive pads. A safety feature to absolutely ensure a secure fit in front of the telescope under any circumstances (gust of wind asf)
• warning text printed onto the front side of each filter cell: Read the Instructions before use
• cardboard gift box fit for safely shipping the filter

ASTF – Baader Solar Filter for high-end telescopes:

2459310 BAADER AstroSolar Telescope Filter 80mm  
2459311 BAADER AstroSolar Telescope Filter 100mm  
2459312 BAADER AstroSolar Telescope Filter 120mm  
2459313 BAADER AstroSolar Telescope Filter 140mm  
2459314 BAADER AstroSolar Telescope Filter 160mm  
2459315 BAADER AstroSolar Telescope Filter 180mm  
2459316 BAADER AstroSolar Telescope Filter 200mm  
2459317 BAADER AstroSolar Telescope Filter 240mm  
2459318 BAADER AstroSolar Telescope Filter 280mm 

Baader Solar Filters are being offered in 21 filter variants and 3 categories. All Filters feature clear white aluminum front frames, powder coated w. IR (heat!)-rejecting paint

ASTF: (AstroSolar Telescope Filter) This family of solar filters is made in the most elaborate way. AstroSolar must not be put under stress, neither during mounting the film, nor during any temperature change. For this reason the ASTF-Filter features a temperature compensated cell. The film itself is repeatably cemented onto an injection molded ring, whereas the substrate of that ring has the same thermal expansion like the Astro Solar Filter material itself. This free floating film carrier ring is held onto the aluminum frame with the help of another holding ring made of fiber reinforced plastic - for a maximum of security against breaking of the cell. This temperature compensated cell enables the AstroSolar filter material to retain its excellent optical quality at any temperature - be it -30°C or +50°C.
ASTF 80 to 280 packages all come with two sets of centering bolts in 38 mm length ( 3 bolts w.10 mm diameter and 3 bolts w. 20mm diameter ) to cover a wide range of tube diameters.

ASSF: (AstroSolar Spotting Scope Filter) This family of filters offers a stable and rigid solution for all spotting scopes, tele-lenses and amateur telescopes, with magnifications up to 120x. The AstroSolar filter material is likewise mounted onto a plastic ring whereas the plastic ring itself works as stabilizing element for the filter cell. This still plastic ring is mounted onto the aluminum front frame. The thermal expansion coefficient of the plastic and the film are similar.
ASSF 50 to 100 packages come with three centering bolts of 13mm diameter and 24mm length. ASSF 115 and 130 packages come with three centering bolts of 10mm diameter and 38mm length.

ASBF: (Astro Solar Binocular Filter) This category is essentially similar to the ASSF in terms of mechanics. The only difference is that one side is cut off in order to make them usable on any binocular – even when the bridge is nearly closed. (depending on the binocular type).
ASBF 50 to 100 packages come with three centering bolts of 13mm diameter and 24 mm height.


Specifications: Baader ASTROSolar Telescope Filter (ASTF)

What's in the Box

What's in the Box: Baader ASTROSolar Telescope Filter (ASTF)

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