Construction of Solar Filters using the Baader Astro Film from AstroPhysics

You must exercise extreme caution when using this film to make filters!!  Any holes or tears can be dangerous, causing blindness!!

I can not assume any liability for your implementation of my filters that are described here.  Please go to the AstroPhysics site and get the complete instructions they have for filter material application and usage.  They have a good amount of information on building filter cells.

Click here to go to the ETX Solar Filter page

Here is a shot of my completed 9X50 finder filter.  It was constructed from 3/16 Plexiglas sheet and ABS plumbing fittings.  It uses the Density 5 Baader film

The plumbing parts consist of a 2" ABS union and a 1/4" thick slice of ABS pipe.  You may need to sand the inside of the union to get a good fit on the scope.

The following seven photos demonstrate the assembly of the filter using household aluminum foil instead of the Baader material.  It turns out the foil was harder to get smooth than the Baader film!

Basically you cut a square of the film and lay it on top of the pipe union with the ring on top.

Press the ring slowly and evenly down into the pipe union until it is seated fully.

Any small wrinkles in the film will not hurt, you must be extremely careful to not tear or pinhole the filter material.

Trim the exposed excess filter material from the pipe fitting cell.

I drilled a couple of small holes through the side of the ABS fitting on the  scope side of the film to vent the pressure created when removing and installing the filter on the scope.

Finished cell installed, outer shield has not been installed.  Do not use the filter in this manner, an exterior shield needs to be added!! The image to the left shows the spotter with shielded filter installed on the telescope.  The filter cell was glued into a hole cut in the shield.  (see pictures at the top of the page)



Copyright 1997-2010 by Bill VanOrden