Astrozap Baader Solar Filter

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  • Regular price $69.00


The sun is a fascinating, dynamic object. Its surface is surprisingly detailed and changes frequently. The observing hours are more convenient. However, there are a few rules to follow before using your telescope on the sun. The first rule of solar observing is never point your telescope at the sun without a proper filter. The second rule of solar observing is always inspect the filter before placing it on your telescope prior to observing to ensure that there are no defects (scratches or pinholes) that could damage your eyes or equipment. If you discover any defects, DO NOT USE THE FILTER—IRREVOCABLE EYE DAMAGE COULD RESULT FROM THE USE OF A DAMAGED SOLAR FILTER. 

Each Astrozap Solar Filter is equipped with one or more plastic retaining screws, depending on the filter's size, that do not mar or scratch the telescope's finish. Astrozap Solar Filters are available in several configurations including full aperture, off-axis and matched pairs for binoculars. Astrozap Solar Filters are proudly made in the USA. When available, Astrozap carries precut sizes of Baader film for the do-it-yourselfer who wants to build a custom sized filter.

Baader film produces a bluish-white image while glass produces an orangey image. Some solar observers believe Baader film provides better contrast. Others prefer the warmer color produced by a glass filter. Buy an Astrozap solar filter and turn your present telescope into a solar observatory. Which filter to choose depends upon personal preference. If you can't decide, buy one of each and compare and contrast the images each filter produces. We'd like to know!

Each Astrozap solar filter size listing represents the outside diameter of the telescope's OTA or dew shield that the filter is designed to cover. We suggest that you measure the diameter of the objective end or dew shield of your OTA in millimeters and select a filter in a size large enough to cover the objective completely. For binoculars, measure the outside of both objective lenses Do not wait until the week of the event to confirm that your solar filter fits your telescope or binoculars, and can be secured in its place in front of your telescope's objective or binocular lenses. Once you receive your order, immediately check and verify that the filter is undamaged, that it fits over the objective(s) completely, and that the adjustment screws tighten enough to hold the filter in place. You must confirm this before attempting to point your telescope or binoculars at the sun in order to ensure that the filter protects your eyes and your equipment. If the filter does not completely cover the objective(s), or is loose and does not stay firmly in place, or if it shows signs of damage, do not use the filter or point your optical equipment at the sun. Ever. Notify Astrozap to obtain a replacement (but if you wait too long, Astrozap cannot guarantee that you will receive a replacement before the event). Failure to verify the integrity, full coverage and secure fastening of your filter before each use will result in damaged optics and permanent injury to your eyes.

With AstroSolar™ the Sun appears in neutral white. Other films and some glass filters produce a blurrybluish or reddish 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 wing of the spectrum.

Due to it's neutral color balance, AstroSolar 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".

AstroSolar™ is essentially free from pinholes, since - other than with even the most expensive glass filters - it is coated on both sides, so that the chance of two pinholes overlapping each other is extremely faint. Pinholes do appear, but to 1 out of 10000 only in optical density 2.5! Baader AstroSolar™ safety film has been approved for eye safety by the National Bureau of Standards in Germany, the PTB. Unlike any other Solar Filter on the market, AstroSolar™ is CE-tested according to EG-Norm 89/686 and EN 169/92 ( notified body 0196). All processes connected to this product have been thoroughly tested. Coatings are inspected constantly for consistency to ensure your eye safety!

Baader AstroSolar™ film Filter cell constructed from lightweight 18Ga. aluminum and powder coated white. Heavy duty threaded inserts and nylon thumbscrews insure a secure fit.

Neither Astrozap nor Mile High Astronomy are liable for damages to persons or property resulting from the user's failure to exercise ordinary care in the ordering, installation, and use of a solar filter.

Telescope Model Outside Diameter
Celestron C5 SCT (5SE, etc) 152mm
Celestron 925 SCT (CPC, Evolution, etc) 273mm
Meade 6000 80mm APO 100mm
Meade 6000 115mm APO 140mm
SKU: AZ-1002