This should have been posted before the transit of Venus
but I have been having a hard time finding some time to work on an ible the past few months. Anyway, this ible will show you how to make your own disposable solar filter for your digital camera using materials accessible around your home.DISCLAIMER: There is no guarantee that this method is safe. However, you can ensure to protect your eyes by using the "digital camera LCD screen" for viewing. As for ensuring the safety of your gadget, all "digital camera sensors" have an IR cut-off filter, and a UV-absorbing thin-film coatings for protection.
Step 1: What You Need?
1) Compact Disc – Compact Discs are made of thick polycarbonate plastic and a thin layer of aluminum making it reflective which in return, reflect back excessive light. Moving on to cutting-off the CD, if you are going to cover large lenses, I suggest you use photographic film exposed directly to x-rays. However, there is no guarantee that the use of the following is safe. Since CDs and DVDs only have thin layer of aluminum, some invisible variables such as IR and UV light can still pass through this thin layer, same as with medical x-ray films, which may cause harm to the eye. Fortunately for digital cameras, you can use the LCD screen for viewing and avoid eye exposure. On the other hand, if you are using a telescope, try acquiring a product particular for solar observing.
2) Cardboard – I found used cardboard at home. A great way to recycle.
3) Glue, Electrical and Clear Tape
4) Cutters and Scissors
5) Plastic Ruler
Step 2: Measure the Diameter of the Lens You Need to Cover With Your Modified Solar Filter.
Fortunately, my camera’s lens is not that big so I could go on using a CD instead of an x-ray film. After measuring, if you have decided to use Compact Disc for this DIY solar filter, you need to carefully peel half of the polycarbonate plastic and retain the reflective side of the CD.
Step 3: Make an Eyepiece.
Draw a circle with the measured diameter of your camera lens and cut it out as shown in the figure below. Make an eye piece by cutting out the corners of the lens and pasting it to the eye piece.
Step 4: Cut the CD for Solar Filter.
Draw a circle with a marker and cut out the CD. After cutting out you may attached it to the eyepiece you made earlier. You may want to let leave and let it dry for a few minutes. Try putting on some heavy book, notebook to make sure that the CD solar filter would be properly glued to the eyepiece.
Step 5: Make a Cylinder to Mount the Eyepiece.
Make a cylinder to mount the eyepiece. Length of the cylinder varies on the length of your camera lens. After you're done with this, you may now glue your eyepiece to the cylinder just to make the sturdy and easy to attach to your camera.
Step 6: Cover the Solar Filter With Black Electrical Tape.
Cover the solar filter with black electrical tape just to make sure that no light will penetrate to the body of the cylinder and the eyepiece.
Step 7: Test Your DIY Solar Filter.
It is important that you test your solar filter first before using it under the sun. I've done the testing using light bulb at home and if you could see the contour of the bulb, then most likely you may now use it under the sun. Use the digital camera LCD screen for viewing. Do not directly look through the camera lens.
Step 8: Sample Output
This was taken during the transit of Venus last June 6, 2012. DIY solar filter color is of bluish hue, I edited and changed to yellow-orange appropriate to look like the sun. More from transit of Venus here