Baader AstroSolar Telescope Filter (ASTF) OD 5.0 (80mm - 280mm)

Baader PlanetariumSKU: 2459318

OTA Outer Diameter and Inner Diameter Size - Please See Chart: ASTF 280 OD: 300mm-340mm ID: 330mm-370mm
Sale price$238 CAD
In stock: 3 unit(s) - Most orders placed by 2PM EST will be shipped out the same day (weekdays)

Customer Reviews

Based on 2 reviews
Tom Z
Good quality, works as expected.

No modifications needed (ASTF 200 fits very nicely on my 8" SCT newtonian -Meade LXD55), fits and performs as advertised. I like the adjustable screws to fit snugly against the frame of the scope. The metal frame is well made.

Jackie O.
Great Product!

Always a stellar experience with Telescopes Canada. Their impeccable service and top-notch products, like the Baader AFTS Solar filter, exceeded my expectations. The quality is unmatched, and their knowledgeable team ensured a smooth and enjoyable buying process. Five stars without a doubt!

Thanks Telescopes Canada!


Baader Solar Filter – The Standard

Mounted Filters with Baader AstroSolar Safety Film OD 5.0

Click here for the Baader Solar Filter Sizing Calculator

After 15 years of offering AstroSolar film sheets as DIY-product, this system of Baader Solar Filters™ is designed to retain the true optical quality of the diffraction limited AstroSolar Safety Film.

  • Safe for solar observation and photography with all high-end telescopes and extreme tele-lenses. Suitable for highest magnifications and detailed observation of individual sunspots
  • AstroSolar Safety Film OD 5.0 is mounted stress free in a temperature compensated cell
  • No astigmatism during winter observation or with temperature changes in summer
  • Supported Scopes: ASTF Filter will fit scopes with apertures from 80 to 180mm (200 – 280mm not yet available). The kit comes with two sets of centering bolts in 38mm length, 3 bolts with 10mm diameter and 3 bolts with 20mm diameter, adjustable to the tube diameter of your telescope or dew cap. In addition, three safety straps with glue-pads and three rubber plugs to cover the holes that are not used, and mounting instructions.

Baader Solar Filters provide a professional and secure solution to observe and image the Sun using AstroSolar® Safety Film OD 5.0. Many ready made filters do stretch the filter material like a drum-head 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 plane-optical 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 float glass.

ASTF - AstroSolar Telescope Filter


ASTF (AstroSolar Telescope Filter)– Baader Solar Filter for high-end Telescopes

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 Scope of supply
Included: ASTF Filter with apertures from 80 to 180mm (200 – 280mm not yet available) come with two sets of centering bolts in 38mm length. 3 bolts with 10mm diameter and 3 bolts with 20mm diameter, adjustable to the tube diameter of your telescope or dew cap. In addition three safety straps with glue-pads and three rubber plugs to cover the holes that are not used. 32-page instruction manual.

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 to come off very hard
  • 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/BDSF-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 (such as gusts of wind)

Please visit Baader Planetarium's website for many questions and answers on their solar products, such as AstroSolar Film, Solar Viewers and mounted Baader Solar Filters.




Filter size Example details for 80 mm
Manufacturer Baader Planetarium
SKU (#) 2459310
EAN Code 4047825032997
Usage Visual solar observation and imaging at high magnification
AstroSolar Film AstroSolar Safety Film
Optical Density 5.0
Inner Diameter / Clear Aperture (mm) 80
Outer Diameter 170
Filter mounted? Yes
Outer Clamping range (10mm bolts) 110 – 140
Inner Clamping range (10mm bolts) 130 – 160
Outer Clamping range (20mm bolts) 100 – 130
Inner Clamping range (20mm bolts) 140 – 170
Solar Wavelength White light (integral light)

Additional Resources

You may also like

Recently viewed