ASBF – Baader Solar Filters for Binoculars and Camera Lenses
Baader's ASBF line of solar filters permit safe visual observation with all types of binoculars or safe solar photography with all camera lenses. The ASBF filters are similar to the ASSF line of filters (for spotting scopes) except that the mounting cell is flat or cut on one side (see photos). This allows you to:
- Use two filters in close proximity to each other on the two objectives of binoculars even for small inter-pupillary (IPD) distances
- Rest a filter mounted on a camera lens on a flat surface without stressing the filter cell or the film, or
- Mount a filter onto a finder close to the main telescope tube.
ASBF-50 Solar Filter Specifications
- Item number: ASBF-50 or 2459325
- AstroSolar film aperture: 50mm (1.97")
- Outside diameter clamping range (with included 13mm bolts): 55 - 70mm (2.17 - 2.76")
- Inside diameter clamping range (with included 13mm bolts): 81 - 96mm (3.19 - 3.78"). See additional info below.
- Suited for aperture range: 40 - 60mm (1.57 - 2.36")
- Outside diameter of filter cell: 110mm (4.33")
- Weight: 2.4oz / 68g
Additional Filter Details and Features
- Made of original Baader AstroSolar Safety Visual Film (ND 5.0), cell mounted, and quality inspected by skilled members of Baader's staff.
- The AstroSolar filter material is mounted onto a plastic ring where 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.
- 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.
- Includes 3 injection molded centering-bolts with threaded brass inserts to center the filter-cell in front of the tube opening (13mm diameter; 24mm length). This fastening system keeps the filter snugly in place and centers the filter. Each bolt features injection molded rubber grip-faces, shaped to easily slide onto any telescope tube but hard to come off.
- No tool mounting and adjustment of the centering bolts to fit a wide variety of mechanical tube diameters. Bolts are made to contact the outside of the optical instrument tube for most applications.
- For some optical items (such as refractor and Newtonian reflector telescopes), you may be able to attach the bolts on the inside of the instrument tube. However, this requires a clear depth of about 20mm on the inside for adequate engagement of the centering bolts which many instruments (like binoculars, camera lenses, and SCT/Mak-Cass telescopes) do not have.
- Includes non-rotating sliding fasteners made from aluminum that hold the centering bolts.
- 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.
- 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 virtually all circumstances.
- Securely packed in a cardboard box with stiff cardboard inlay for safely shipping the filter; Instruction booklet included.
About Baader AstroSolar Film and Solar Filters
The world's finest objective solar filter material - Baader Planetarium's AstroSolar Safety Film - is now available in a complete range of high-quality mounted Baader Solar Filters. Their innovative design and construction enables each filter to fit a wide range of instruments - from high end telescopes, to spotting scopes, camera lenses, and even special versions to fit binoculars. Each filter is precisely mounted at Baader onto special cells, guaranteeing a stress-free mounting that preserves the full optical quality of the AstroSolar film.
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. However, this absolutely destroys the image quality, rendering the film useless for high magnification work. AstroSolar is mounted entirely stress free onto Baader's filters in order to perform like a high precision plane-optical window. Even though it may seem counterintuitive, Baader AstroSolar film must show slight ripples! When the film is put under stress by an improper cell mount, its optical quality is degraded and it performs just like a common coated glass-filter made of untreated float glass.
In its September 2000 issue, Sky & Telescope magazine proclaimed Baader Planetarium's AstroSolar Safety Film to be "the new standard in solar filters." AstroSolar Safety Film delivers white light views of the Sun that are unmatched by any other objective solar filter or material. The views through AstroSolar display fine solar details, including fine penumbral detail, solar granulation, and lighter colored faculae. The disk is set against a dark background, free of the haze and scatter that is common in typical 'mylar' films or inexpensive glass filters. The performance of Astro Solar Filter Film is even more remarkable when considering its very low cost.
What is even more important - with AstroSolar Film the Sun appears in its real color - neutral white (with only a slight bluish tinge). Other films and glass filters produce a blurry bluish or reddish/orange/yellow Solar image, thereby cutting part of the spectrum. Especially with an orange sun, it is very hard to see faculae regions which are visible predominantly in the blue portion of the spectrum.
Due to its neutral color balance, AstroSolar Film enables the use of various color (or interference) filters which allows the observer to concentrate on certain spectral passbands for investigations of different layers within the solar "atmosphere". It is also possible to further improve the stability and sharpness of the solar image through the use of the Baader Solar Continuum Filter (sold separately). Views of granulation and faculae are particularly enhanced through the use of this continuum filter, in combination with AstroSolar film.
Please note that you cannot see solar prominences with white light solar filters such as this - that requires the use of sophisticated and significantly more expensive narrowband solar filters or telescopes. Solar filters made with AstroSolar Film with a neutral density (ND) of 5.0 can be used for visual and photographic, imaging and video applications.
Oct 3, 2017
Very nice white light solar filter.Pros: Cons: Comments:
Very nice white light solar filter. I got it to use on a small telescope and on camera lenses. I really like the natural color of the image using this solar filter. The three adjustable "feet" are very stable, and the filter included velcro attaching straps if even more stability is desired - I personally don't find the straps necessary. The filter comes very well protected in a box, and I use the box for storage when not using the filter. Highly recommended.
This review was provided courtesy of AgenaAstro.comAug 31, 2017
Excellent timing!Pros: Cons: Comments:
I needed this for the recent solar eclipse that I used on my camera and was pleased with the easy setup and overall use of this product. And the company shipped it out and I received it within a week!
This review was provided courtesy of AgenaAstro.comAug 30, 2017
Agena rocks!Pros: Cons: Comments:
Don't know how they did it but they got the filter to me just days before the eclipse even though I ordered it at the last minute. The filter itself was excellent by the way.
This review was provided courtesy of AgenaAstro.comAug 27, 2017
Very nice solar filtersPros: Cons: Comments:
I bought a pair of these filters for my binoculars (Nikon Astroluxe 18x70) to watch the recent solar eclipse. The filter set as less expensive than glass filters I had also been looking at, and they worked as expected. The image was a bit on the bright side but I was able to resolve sun spots and other detail in white light. I'm not a huge fan of the design with the three legs, but between those and the safety straps and velcro, the filters were held securely on the binoculars. My only minor complaint is that the boxes the filters came in could be just a little bit deeper so they could be used to store the filters better once they've been assembled. Overall, I'm pleased with the purchase.
This review was provided courtesy of AgenaAstro.com
saint327 New Member
- Skill Level
- Time with Product
Jul 31, 2017
- User Notes:
- Review by Michael H.
Simple design with qualityPros: Cons: Comments:
Bought these for the upcoming eclipse and they are great. Easy to setup and fits my skymaster 15x70 really well. One thing I would say is the solar for is fragile and can be easily scratched. Not to the point of the coating getting removed but potential loss in visual quality. so be careful around that
This review was provided courtesy of AgenaAstro.comJul 13, 2017
Works great. Wish the boxPros: Cons: Comments:
Works great. Wish the box were about 1/4 inch deeper so that it could be used to conveniently store the assembled product. This is the second AstroSolar filter I have purchased. Both work well.
This review was provided courtesy of AgenaAstro.comJun 15, 2017
Baader AstroSolar Filter for Binoculars & Camera Lenses - 50mm FilPros: Cons: Comments:
Baader AstroSolar Filter for Binoculars & Camera Lenses - 50mm Filter Aperture # ASBF-50 from Agena AstroProducts works entirely as advertised. Filter "color" is great across the spectrum. Velcro straps are a great feature for temperamental lenses. The adjustable sizing can also be used to "regulate" the tightness of the grip on the lens.
This review was provided courtesy of AgenaAstro.comMay 12, 2017
Best clarity availablePros: Cons: Comments:
Basically zero sunspots since I received this, but fot the few that have appeared, I've had the best views ever. The only reason I didn't give five stars is, once assembled, it doesn't fit back in the box. Another quarter of an inch and the shipping box could have doubled as a storage box.
This review was provided courtesy of AgenaAstro.comMay 6, 2017
Excellent ServicePros: Cons: Comments:
Haven't used the filter yet, but Agena's website is easy to use and always has good product info. Never had any problems including returns. Always fast service across the board. They are one of my favorite astro stores. Highly recommend.
This review was provided courtesy of AgenaAstro.comApr 9, 2017
Great view of sunspot. IPros: Cons: Comments:
Great view of sunspot. I use this on my finder and a 200mm model on my C8. A Baader orange filter on the eyepiece provides a more intuitive color of the sun.
This review was provided courtesy of AgenaAstro.comMar 31, 2017
Great performance and engineering, good conveniencePros: Cons: Comments:
These are top quality filters that are thoughtfully designed. They come apart, so the film itself is replaceable. Mounting is secure but a little ungainly: the ability to accommodate multiple size objectives makes the mounting a bit fussy.
This review was provided courtesy of AgenaAstro.com
Dick Gentry New Member
- Skill Level
- Time with Product
May 13, 2016
- User Notes:
- Review by some call me bad things of Dallas, Texas.
Fine performance from Baader ASBFPros: Cons: Comments:
After reading the Baader solar film was very effective, I bought the ASBF model to fit my 10x50 binoculars. I hoped they would be adequate so that I could observe the Mercury transit. New to solar observing, I put them to use checking out sunspots. They worked well for that and I found my sightings verified by more sophisticated posted solar images. The day of the transit was very cloudy early but cleared enough I peeked through sucker holes and easily picked out the planet crossing the sun's face. After lunch it cleared enough I watched 3rd & 4th contact as the transit finished. I was very gratified.
But nothing's perfect. The adhesive on the tabs that are supposed to secure the velcro tabs for the safety straps to the binos failed miserably to stick to anything. So I substituted appropriate tabs with real adhesive and the safety straps are in place.
With that minor caveat, these filters are great performers and highly recommended.
This review was provided courtesy of AgenaAstro.comSort by
Manufacturer Baader Planetarium