Baader AstroSolar Telescope Filter 240mm
Product Code: 1594696

Baader AstroSolar Telescope Filter 240mm

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Baader Solar Filters provide a professional and secure solution to observe and image the Sun using AstroSolar Safety Film. Many ready-made filters stretch the filter material like a drumhead in order to make it look like a piece of glass – this absolutely destroys the image quality, rendering the film useless for high magnification work. AstroSolar film must be mounted entirely un-stressed 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!

Baader AstroSolar Filters:

Baader Solar Filters are available in 21 filter variants and 3 categories. All Filters feature clear white aluminium front frames, powder coated with IR (heat) - rejecting paint.

AstroSolar Telescope Filter (ASTF):

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 features a temperature compensated cell. The film itself is repeatedly cemented onto an injection moulded 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 aluminium frame with the help of another holding ring made of fibre reinforced plastic - for a maximum of security against the cell breaking. 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 80mm to 280mm packages all come with two sets of centring 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.

AstroSolar Spotting Scope Filter (ASSF):

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 stabilising element for the filter cell. This still plastic ring is mounted onto the aluminium front frame. The thermal expansion coefficient of the plastic and the film are similar. ASSF 50mm to 100mm packages come with three centring bolts of 13mm diameter and 24mm length. ASSF 115 and 130 packages come with three centring bolts of 10mm diameter and 38mm length.

Astro Solar Binocular Filter (ASBF):

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 50mm to 100mm packages come with three centring bolts of 13mm diameter and 24 mm height.

Baader Solar Filter Specifications:

  • Original Baader AstroSolar® Safety Film (OD 5.0), cell mounted and quality inspected by skilled technicians
  • 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 moulded centring-bolts with threaded brass inserts to centre 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 moulded 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 centring 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 aluminium that hold the centring 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 centring 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 aluminium frame for blocking sunlight from passing through the filter cell beside the filter area; for ASTF-filters only, rubber plugs supplied as cover for closing unused adjustment slots in the aluminium 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
  • Warning text printed onto the front side of each filter cell: Read the Instructions before use
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Product Code: 1594696-wex Manufacturers Part Number: 2459317