Solfilterfolie AstroSolar® OD 5.0 A4 210x297mm

It's always very pleasant to observe the Sun, not only during solar eclipses. The number of sunspots changes permanently, as well as their shape and size. Depending on magnification, you may even be able to discern the core and boundary areas of a sunspot (umbra and penumbra). The one essential condition for any solar observation is to reduce the sunlight to under 1/100.000 of its normal brightness, which is a no risk amount for the eyes. The Astro-Solar sun filter foil meets that standard. Simply fitted to the front of the telescope tube, this foil doesn't fall short of pricey plane-parallel glass filters in any way. The coating is subjected to permanent quality control. The multiple metal coating of the foil produces a remarkably even filter effect.

Technical data:

• film size: 20 x 29 cm
• filter efficiency: 99.999 % (ND = 5.0)
• film thickness: 0.012 mm
• absolutely clear and bubble-free substrate (non-Mylar)
• instrument requirements: for telescopes, binoculars, spotting scopes and eyeepieces of up to 152mm aperture
• quality mark: CE
• Included in delivery: 1 A4 size sheet, incl. instructions, in PE sleeve