You can make your own inexpensive high density filter to photograph the eclipse. But there is a catch. It is not safe to use to look at the sun, and you should not look through the viewfinder of the camera because you could go blind or suffer serious, permanent eye damage.
Originally posted August 6, 2017. Revised and expanded August 14, 2017.
High density filters (and some other kinds of filters) are photographically safe but not visually safe. They are called “high density” because they dramatically reduce the amount of visible light. They are safe to use on your camera but they are not safe to look through because they do not eliminate UV and IR light. When you use high density solar filters that are not visually safe you must use your camera in Live View mode. You must not look through the viewfinder of the camera. This article and this article explain why in greater detail.
Making Your Own Solar Filter
To make you own filter you will need some solar filter material. Order “Baader AstroSolar Visual Solar Filter Film”. You can order it here from Amazon. If you have been reading the other eclipse articles I have written you are aware that I am telling everyone it is not safe to order eclipse glasses from Amazon. This is an exception because you will be using this make-it-yourself solar filter photographically, not to look at the sun.
There is one big problem with this plan. The Baader solar filter material will not be in stock until August 13. Then it will need to be shipped to you. The eclipse is August 21. If you are afraid that is cutting it too close and you want to order a commercial high density filter, read this article.
Despite what it says on the Amazon web site, this Baader solar filter material is NOT safe to look through at the sun. More about this later.
Once you have the solar filter material from Baader (it measure 5.5 x 6.1 inches) you will need to make a cardboard housing to hold it on the front of your lens. You will need to cut a circle out of the Baader filter material that is bigger than the front of your lens. Then mount the Baader filter material in a piece of thin cardboard that you can fold up into a filter housing that will slide over the outside of your lens. You can use the shape (above) of this commercial unfolded cardboard mounted solar filter to give you an idea how to construct your own cardboard filter housing. Make sure there are no gaps between the edges of the Baader filter material where it meets the cardboard filter housing.
When you are done folding it up and taping it together, it should look something like this commercial solar filter. Slide it over your lens to use it and tape it to your lens so it doesn’t fall or blow off your lens.
Just remember that despite what it says on the Amazon web site, this solar filter material is NOT safe for viewing the sun. This is why. This a Baader’s “AstroSolar Safety Film”. In this article by the American Astronomical Society (AAS), they have this note:
“Note: Baader Planetarium’s AstroSolar Safety Film and AstroSolar Photo Film, sold in the U.S. by Alpine Astronomical and Astro-Physics, are not certified to meet the ISO 12312-2 international safety standard and are not designed to work as eclipse shades or handheld solar filters.”
Baader does make “AstroSolar Silver/Gold Film”, but that is not what is being sold at Amazon. AstroSolar Silver/Gold Film is for “eyes-only direct viewing of the Sun”, i.e., for making your own eclipse glasses, but not for use on camera lenses, binoculars, or telescopes. So even if you could find the AstroSolar Silver/Gold Film you can’t use it for photography.
Based on the recommendation of the AAS, you should not use your Baader solar filter visually. It is not safe to look through the Baader filter at the sun, and, as I said before, you must not look through the viewfinder of the camera when the lens (with the filter on it) is pointed at the sun. More about safety in this article: Do NOT Look at the Eclipse Through a High Density Solar Eclipse Filter! You Could Go Blind!
To learn how to photograph the eclipse using your homemade Baader high density solar filter, read How To Photograph the Sun (and an Eclipse) with Lee and Other High Density Solar Filters.
Safe Eclipse Glasses
The Great American Eclipse Series
High Density Solar Eclipse Filters from Adorama – Go to this article if you decide you don’t want to make your own filter.
You Can Still Buy Safe Solar Eclipse Glasses if You Act Now! Written August 5, 2017.
How to Tell If Your Eclipse Glasses or Handheld Solar Viewers Are Safe – the American Astronomical Society
Reputable Vendors of Solar Filters – the American Astronomical Society