Types and uses of Budd membrane

5.0 Bader film can effectively filter out the brightness of 40W incandescent bulbs. Through the film of 5.0, you can clearly see that the bright silk of this light bulb is like hair.

3.8 Budd film can not effectively filter out all the brightness of 40W incandescent bulbs. Through the film of 3.8, not only the filament of the bulb but also the outline of the bulb can be clearly seen.

The membrane transmittance of 3.8 is 5.0 16 times, when the sun is normal brightness. 3.8 visual glare, can't see the details of the sun. 3.8 is suitable for taking photos, and 5 is suitable for visual inspection. However, it is ok to take photos with 5, but the exposure time is slightly longer. In addition, when shooting the total solar eclipse, Budd's film should be taken down early, otherwise it will miss the wonderful moment, a very short moment.

The traditional method is to use neutral gray filter when observing solar activity, solar eclipse and taking photos of the sun. But now there is a new filtering method which is cheaper, more effective and has higher performance. This is an invention patent from Germany-Astro Solar TM, which has been registered in Europe/KOOC-0/9 countries with the registration number of 99/KOOC-0/0/KOOC-0/807.8.