4"x4" Solar Filter Sheet for Telescopes, Binoculars and Cameras

Full disclosure: First solar eclipse photo op for me! I have multiple total, and partial, lunar eclipses in my experience base but no solar chops! Until now. The Thousand Oaks Optical brand solar filter is quite economical, if you're on a tight budget, or just frugal by nature. And there's also the argument against buying an optical glass, dedicated size, filter for one lens or telescope aperture! The T.O.O. filter is metallized Mylar film, not glass! You can buy the size for the largest lens or telescope you own and then adapt it to smaller lens sizes as needed, with a bit of additional fabrication. I adapted the 4" X 4" filter to fit the sunshade of a 70-300mm zoom lens, which I could fit on, or remove as needed. I fabricated a filter mount from white card stock and Scotch Magic Tape. As such, the fit was secure enough to not need any additional support. If it was really windy, a few pieces of Magic Tape would have secured it to the sunshade!I made some test exposures well before the event started and dialed in a starting exposure and captured the image in pic 1. Sunspots are visible in the center and left of center. Cloud cover interrupted the rest of the event, and pics 2 and 3 are marred by wispy clouds moving across the frame. As my location was several hundred miles east of totality, the eclipse was a partial for me. I was happy to have caught what I did and gained some experience from it too. The filter performed exactly as presented! Please note: The filter can be used, as delivered, by simply folding and taping the corners to whatever optical device you plan to use. However, there's a risk of leaving a gap through which sunlight can pass, causing damage to the eye or optical gear! There are a number of sites online dedicated to amateur telescope making that have information on fabricating and adapting all sorts of gadgets and accessories for astronomy Do it right, you only have one pair of eyes.Safe viewing and clear skies!! Hope this helps

It's a great cheap option for a scope if you can't afford a real filter. Works as it should.

Good quality and the size was good.

I used these to make filters for my binoculars for the April 8 2024 eclipse. Overall they worked OK (glad I had them), but not great. I knocked off one star because they were a little darker than I expected, and one star because they are so fragile. The fragility I could have prepared for, but the listing has so little info I was not aware until they were scratched enough to affect image quality. You might consider this user error, but considering that probably most people are like me using this for a specific event that you don't get a second chance at, I feel like this really should be stated clearly up front and I would have been OK with it.Regarding darkness, with my 10x42 binoculars, it looked good but noticeably (but not enough to matter much) darker than looking at the sun through solar glasses without magnification. With my 7x35's, it was quite a bit darker, making it not much easier to see more detail than through solar glasses without magnification. It may be that these are intended for higher quality devices but these are what I use for birding without issues.Regarding scratching, I cut out circles of this material and glued them into 4 frames I 3d printed to fit on 2 pairs of binoculars. Once they were complete, I put them in a small box to protect them, but in the box they could move around a tiny bit. Shortly before C1, I put them on my binoculars and left them on until totality. I was pretty careful with my binoculars like I usually am, but I would do things like put them in my lap or on a table on top of some clothes where the could run against clothes. Around the time totally ended, they were so scratched that the image quality was reduced to the point that I could no longer see any more details with binoculars than without. Over all, I got some good views of the eclipse before totality with them, and they weren't very useful after totality due to the scratches.

We bought these in preparation for the great solar eclipse. Granted, that's not something that happens every day, but we were very pleased that we could see sun spots with our telescope. When I told our homeschooling co-op about it, they thought it was cool and now we are planning on an activity where I bring it and all of the kids can see the sun in a telescope. It worked perfectly and was safe. It was a bit of a process to customize it for our telescope, but was definitely worth it. Plus we looked, and it was a lot cheaper to go this route than to buy a dedicated telescope for sun viewing. This was a great value!

I bought this to get ready for the 2 solar eclipses heading through Texas in the next year.I bought the 4". I had an extra UV filter, so I cut the solar filter to fit inside the UV filter. As you can see in the photos, I didn't cut a great circle, but no extra light got into the photo which was a pleasant surprise. It also allows me to tape the leftover plastic to sunglasses to view the eclipse. All for a very affordable price!I wasn't sure which way to install the film... metallic side towards the sun or the black plastic side, so I wrote the seller. A quick reply was that the metallic side faces the sun. Probably avoids the plastic overwhelming and warping.After playing with the settings a bit, I got the pic attached to this review at 200mm zoom with ISO of 500, and stopping down -1 2/3. At that level, I was able to get a sunspot, which can be seen in the lower right corner of the sun! This pic was taken handheld while sitting in a reclining chair. Not bad for an amateur first sun pix. Other pix show the sunspot in the same place, so it's not an imperfection in the filter or lens.For a fraction of the cost of a solar filter, you can get essentially the same thing. That makes it perfect if the solar eclipse happens when it's cloudy making the whole effort moot.