BDSF: OD 3.8 Baader Digital Solar Filter (80mm - 280mm)

More Views

Application Images

Images uploaded by Customers

Add Your Review with Images
BDSF: OD 3.8 Baader Digital Solar Filter (80mm - 280mm)

Please choose product variant below to see price and SKU number

€ 92.00 Price excl. German VAT tax (19%): € 77.31

Please choose product variant below to see stock status  

Baader Solar Filter Finder Tool
  • NOT suitable for visual solar observation. Only use for digital imaging with all high-end telescopes and extreme tele-lenses (lucky imaging technique). Suitable for highest magnifications and detailed imaging of individual sunspots
  • AstroSolar PHOTO Film OD 3.8, mounted stress free in temperature compensated cell
  • No astigmatism during winter observation or with temperature changes in summer
  • Scope of Supply: BDSF (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, mounting instructions.
Important note: Please use our Solar Filter Finder Tool to find the fitting filter for your instrument.

* Required Fields

€ 92.00 Price excl. German VAT tax (19%): € 77.31

Product Questions and Answers

Do you have a question about this product? Then we would like to ask you to first look through the existing questions and answers, most likely your question has already been answered and you will get the desired information much faster this way. Your question is not listed? Then please click on the button "Ask a question".

Sort by ASC
I have a Canon 600mm f/4 IS lens with a cap that has an outer diameter of 184mm/7.25 inches do you have a BDSF: OD 3.8 Baader Digital Solar Filter that will fit?
Question by: Jens Lambert on Jul 18, 2020 8:27:00 PM | 1 Answer(s)

Rating of Question

When will the OD 3.8 filters in diameter 240/280 be back in stock? I haven't seen them in stock for a long time. Thanks a lot!
Question by: Eduardo Schaberger on Jan 3, 2021 3:33:00 PM | 1 Answer(s)

Rating of Question

Hi, I have a Canon 400mm DO USM f4 lens with hood and would like to know which BDSF: OD 3.8 Baader Digital Solar Filter (80mm - 280mm) would fit my lens for the purpose of digitally photographing the Annular Eclipse this October and also the Total Solar Eclipse this coming April 2024. I appreciate your assistance.
Question by: Deb on Aug 23, 2023 9:11:00 PM | 1 Answer(s)

Rating of Question



Baader Solar Filter - Features

Baader Solar Filter – the Standard

ATTENTION: Baader Digital Solar Filter with AstroSolar® PHOTO Film OD 3.8

The Baader Digital Solar Filter with PHOTO-Film OD 3.8 is a development made possible after the product launch of our Baader Solar Filters OD 5.0 in spring 2015. The filter has the same cell and mechanical specifications as our ASTF-Filter with Safety Film OD 5.0, the only difference lies within the used AstroSolar Film – our AstroSolar PHOTO Film OD 3.8 which has proven itself over the years. This film allows shortest exposure times – mainly used for digital videography and the lucky imaging technique – and thus almost “freezes” turbulences in the earths atmosphere. AstroSolar PHOTO Film OD 3.8 is NOT intended to observe the sun, only for digital imaging!

Many ready made filters do stretch the filter 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.

BDSF - AstroSolar Digital Telescope Filter


Application examples

ASTF/BDSF (AstroSolar Telescope Filter)– Baader DIGITAL 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.


BDSF Scope of supply
Included: ASTF/BDSF 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:

  • Only for BDSF-Filter: original Baader AstroSolar® Photo Film (OD 3.8), 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 (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
Related Articles

Additional Information

Technical Data not yet specifiedPlease choose product variant from dropdown above to see technical data of your chosen product

You may also be interested in the following product(s)

Overall Average Rating:
2 reviews
5 star
4 star
3 star
2 star
1 star
  • Date - Newest First
  • Date - Newest First
  • Date - Latest First
  • Highest Rated
  • Lowest Rated
  • Most Helpful

2 Item(s)

Michael S. 249/09/2020 06/09/202006:46
  • Rating:
Baader Astrosolarfolie ND3.8 - erster Einsatz
Am Sonntag, dem 7. Juni 2020, erbarmte sich das Wetter endlich und ich konnte die BAADER ASTROSOLARFOLIE ND3.8 in Kombination mit dem Ca-Line Filter an der ZWO Asi monochromen Kamera ausprobieren. Das Seeing war durchschnittlich, die Transparenz am Vormittag noch recht gut.
Die Durchlässigkeit der Folie kombiniert mit dem recht stark abdunkelten Filter harmonierte ohne Verwendung einer Barlowlinse am 6 Zoll APO Refraktor mit 1050mm Brennweite sehr gut, also sehr kurze Belichtungszeiten für die Kamera möglich. "Montiert" wurde die Folie mit Hilfe des beiliegenden Zubehörs - Klettverschlüssen, an der verlängerten Taukappe, was einen sicheren Betrieb gewährleistet. Aktuell ist die "Action" auf der Sonnenoberfläche noch sehr gering, um hier ein spektakuläres Bild beizusteuern, aber zumindest eine erste Fleckengruppe vom Zyklus 25 war vorhanden.
  • Einfache Handhabung, sicherer Einsatz.
Show more comments (-5) Hide comments
Frist 64/03/2018 06/03/201808:41
  • Rating:
Neuer Filter für mehr Kontrast
Ich beobachte bereits seit mehreren Jahren mit einer solchen fotografischen Folie die Sonne. Die Halterung habe ich mir dazu aus Tonkarton einfach selbst gebaut.
Nun ist meine Folie allerdings etwas in die Jahre gekommen. Der Tonkarton ziemlich abgegriffen und eingerissen - die Folie bekam kleine Löcher und ergab ein immer schlechter werdendes Bild. Warum nicht gleich fertig mit der Halterung kaufen?
Der Zusammenbau der Halterung war völlig problemlos möglich. Man sollte vorher überlegen, welche Löcher genutzt werden müssen. Sonst muss man wie ich doch noch mal umbauen, wenn das Teleskop zu klein ist! Aber auch das kostet nur wenige Minuten.
Der erste Blick durch die Neuanschaffung hat mich dann sofort überzeugt. Endlich wieder ein kontrastreiches und klares Bild! Im direkten Vergleich zur alten Folie erscheint das Bild etwas rötlicher und dunkler, aber sehr viel kontrastreicher.
Einziges Manko ist die Verpackung. Wenn man die Halterung zusammen gebaut hat, passt sie von der Höhe her nicht mehr in den Karton. Den Folienfilter will ich aber geschützt aufbewahren. Also musste ich einen anderen beschaffen.
  • kontrastreiches Bild, erlaubt kurze Belichtungszeiten, einfache Handhabung, geringes Gewicht
  • Verpackung zu niedrig für dauerhafte Aufbewahrung
Show more comments (-5) Hide comments

2 Item(s)

What kind of abuse are you reporting?
    Please, wait...