How to make a simple White Light Filter

A quick guide on how to make a White Light Solar Filter for a scope with a removable centre cap.

For Visual you only need a small (1-2 inch ) hole, as the Sun is very bright, any larger you may find it to bright and need to add extra filters to dim it down a bit.
All you need is a piece of Baader visual film (they make 2 types, visual which is ND5 which is for visual use, and a Photo film which is ND3.8 and MUST be ONLY used for imaging not visual, not even by looking through the viewfinder of a DSLR camera)
Also need a bit of cardboard, any old box will do.

Remove the center cap of the lens dust cap, note I have put red tape round the end of the telescope tube, this makes the dust cap a very tight fit (don't want it falling or blowing off when looking at the Sun), and also a visual guide to show the cap is not on.
Next draw round the cap to make a ring.

Cut out the shape to make a ring that fits inside the front cap.

Then do a test fit to make sure the center hole is in the right place.

Glue sometimes melts when out in the Sun for a while, so it is advised to use good double sided tape, carpet tape is ideal for this.
Put strips onto the card to stick the baader film to.

The best and easiest way to stick the film on is to lay the film on a flat surface (remember it has a protective clear film on one side and sometimes a tissue paper on the other), when the film is flat, slowly lower the card ring on top.  It does not really matter if it is not absolutely smooth, as even a few wrinkles wont make a difference to the view.

Trim the corners off the film so it is level with the card, then with the double sided tape, put a few more on the edge of the card/film, making sure not to cover the centre (or you won't be seeing a lot).

Then simply place the filter into the inside of the dust cap and press firmly in place.

And there you have a white light scope for viewing the Sun.
Before each viewing you MUST check the filter for pin holes, the best and safest way is to let the Sun reflect through the filter onto the floor or a bit of paper, and if there are any holes in it, there will be bright spots as the filter is letting through pure sun light, if it produces a dark shadow with no bright spots then it is working fine and can be put onto the scope and safely used.

Use the centre cover to protect the filter when not in use.

Remember to remove the finder from the scope when viewing the SUN....
See my other guide on how to make a quick and easy SAFE Solar Finder.

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