Introduction: DIY Solar Filter for Camera
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
6) Marker
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.
13 Comments
Question 1 year ago on Step 4
Do we need the polycarbonate disk or reflective disk?
5 years ago
I usually watch through two compact disks. It blocks the light even further.
Reply 1 year ago
Thanks, it will not hurt my Mobile camera😊
2 years ago
hey.. great instructable.... i want to use this on my 60mm telescope and take pictures of it on my phone camera. will it burn my phone camera?
7 years ago
How you split the CD? please tell me???
7 years ago
Is this work for SLR camera?
9 years ago on Introduction
Mylar balloons also work well. Just do not pull the mylar tight; the stretching can cause distortion. I'ld also echo that this is not something I would trust my eyes with but looking at a screen on the camera, totally safe.
10 years ago on Introduction
Ok Captain Safety hat on for a second...
I initially started this as a "waaah! dont do that!" post but I've done some digging and thought you might be interested.
According to NASA
"More recently, solar observers have used floppy disks and compact disks (both CDs and CD-ROMs) as protective filters by covering the central openings and looking through the disk media. However, the optical quality of the solar image formed by a floppy disk or CD is relatively poor compared to mylar or welder's glass. Some CDs are made with very thin aluminum coatings which are not safe - if you can see through the CD in normal room lighting, don't use it!!"
It goes on to say you should never use a filter like this in conjunction with an optical device ie a camera. I'd say I wouldnt use it with a camera where you actually look through the lens ie a digital SLR - but with a cheap digital camera all you're risking is the camera itself.
Actually you could use almost the same design and replace the cd's with a sheet of "baader solar film" it will work even better. The film comes in A4 sheets and costs £20 (sorry not sure about US costs). Or buy a pair of eclipse specs and carefully cut the film out. Less frugal but a single A4 sheet would make half a dozen filters.
Sorry - hat removed !!
T
:D
Reply 10 years ago on Introduction
Thank you for your comment!
I'm initially aware of the Baader solar film and have used it in the past. However, I mentioned in my ible that my goal is to create a solar filter from parts you can easily acquire at home, I think I just forgot to mention the use of digital camera LCD screen for viewing and have added it on my disclaimer, thanks for reminding me! :)
As for risking the camera, I think it's also safe because all digital camera sensors have an IR cut-off filter, and a UV-absorbing thin-film coatings for protection.
10 years ago on Introduction
Epic... coolness
Reply 10 years ago on Introduction
Epic frugalness. XD
10 years ago on Introduction
cool! I had no idea cd could be used this way! is it hard to peel off the plastic from the cd without breaking it?
Reply 10 years ago on Introduction
Hard at first, but when you get to the point when you have separated the polycarbonate plastic, you just need to slowly peel it off and everything should be easy by then. :)