Baader Planetarium AstroSolar® Safety Film ND5.0 has been in production for more than 25 years. In that time, not one single person has been injured or has suffered eye problems during – or long after – using AstroSolar® Film for observing the sun with the naked eye or through any kind of optics up to one metre in aperture.
Since a new ISO-norm (12312-2:2015 for eye safety came into being, we have no rights to declare the old DIN-norm EN 1836 safe for direct “eyes-only” solar viewing, e.g. with eclipse viewers. However – as long as that old norm was in place, we had collected 25 years of experience though. In all this time we did not receive information about any single case of eye irritation or eye damage while approx 20 Million people each used one Baader solar eclipse viewer equipped with a single layer of AstroSolar Silver film to directly observe the sun.
Baader do supply AstroSolar® to two sources in the U.S. and from there AstroSolar® is being offered at Amazon and multiple dealers. As long as you purchase the original size of Baader ECO-Film (EAN# 2459286) or Baader A4 Film (EAN#2459278 ) or Baader 100×50 cm film (EAN#2459282 ) you are sure to receive a genuine Baader product. And we wholeheartedly recommend all makes of ready-made solar filters in cell mounts for most telescope sizes – as long as they are being produced in Germany or inside the USA (such as Kendrick or our Baader cell mounted filters ASTF/ASSF/ASBF).
In 2015 the new ISO-norm 12312-2:2015 had been installed for eclipse viewers only, which requires a tiny fraction of higher optical density in the UV as added safety measure for meeting possible law problems in the U.S. For this reason AstroSolar® Film would still remain the only diffraction limited film for using in front of any optical device but must not be recommended anymore for producing eclipse viewers without adding reduction of UV-transmission.
Baader state that there IS NO STANDARD for for any type of solar filter except eclipse glasses and other solar viewers meant to be used for eyes-only direct observation of the Sun. That’s what the ISO 12312-2:2015 standard applies to — nothing else. How do Baader know that their solar filters are safe for use with telescopes, binoculars, and camera lenses as they come from reputable manufacturers whose products have been tested by people with access to the appropriate equipment — such as optometrist and eclipse chaser Ralph Chou of the University of Waterloo — and found to be safe, and because they have been used in the field by thousands of astronomers without any problems for years.
AstroSolar® is the single highest-quality material in the world for producing front objective filters for Telescopes, Spotting Scopes, Binoculars and Cameras – but the film alone must not be advertised anymore for production of eclipse viewers – unless you combine it with an added layer of dark film – or use it together with dark sunglasses which are blocking the UV anyhow. But even in this case you would not create a product that is ISO-compatible because this very product of yours might be perfectly safe – but it had not been officially certified to be so. Talking straight – your homemade eclipse viewers would not become ISO-compliant anyway, because it is not enough to just use ISO-certified film – the finished viewer would need to be ISO-certified as a whole, in order to be completely lawful and to not present any risk – to the seller. Any self-made DIY paper-film-holder that might be blown away or that might not cover the face well enough would become “risky business” – with hysteria about solar eclipse eye safety running to a peak within these very days. But if you are not selling your DIY-product but are proudly using it for yourself and with your family – were is the judge that will ask about the certification of your private DIY-activity?
For Baader’s new and ISO-compliant solar eclipse viewers they had combined AstroSolar® Silver film with a special made dark film that has the same properties as a very dark pair of sunglasses – completely blocking the part of the spectrum below 400 nm. This combination has been ISO-certified – which is very expensive and time consuming. The results of this certification process is registered at the AAS as stated above.
Baader do recommend AstroSolar® Safety Film as single sheet without any extra layers for making solar objective filters for astronomical/terrestrial optics with all care taken. This is lawful and does retain the value of the film. If used for eclipse viewers the true optical quality grade of AstroSolar® would be wasted somehow. AstroSolar® film has the same properties as a precision polished plane-parallel piece of optical glass and hence is good for 250x magnification and more, which is much better than any other solar film or “economy-priced” glass filter on the planet.
August 14th, 2017
Baader Planetarium GmbH