Homemade solar eclipse viewer

Homemade solar eclipse viewer

Today,while watching the news I saw about solar eclipse that was going to occur on 21 June 2020.As we all know that solar eclipse should not be viewed with naked eye,so i decided to make a solar eclipse viewer at home :thinking:.

The things needed to make it are:

1.Cardboard box.
2.Aluminium foil.
3.Scissors or cutter.
5.White paper.
6.Safety pin or needle.

Here are the steps to make it.

1.Cut the piece of white paper same as the one side of box and paste it on that side.

2.Now make two holes on the opposite of side on which white paper is pasted.

3.On one of the two holes paste aluminium foil paper

4.Make a small hole in the aluminium foil paper with the help of safety pin or needle so as sunlight can pass through it.

5.Make sure that no other hole is remained open (except the two holes you have made) through which sun light can enter the box.
6.Watch the solar eclipse by adjusting the box.



Kindly share images of the eclipse.


Sorry,Sir but I was unable to capture the images of solar eclipse.Solar eclipse was visible through it but when I tried to take pictures the solar eclipse,it was not visible in the picture. :disappointed_relieved:


Hi Manpreeth,

No issues that you could not capture the images of solar eclipse. But the fact that you could see the eclipse through it is wonderful and proves that the viewer is working :smiley: :smiley:.

Moving ahead, can we try and understand how this might have worked, and what the underlying principles are?

Perhaps, we might be able to use this instrument somewhere else too? :thinking: :thinking:



Pinhole cameras rely on the fact that light travels in straight lines – a principle called the rectilinear theory of light. This makes the image appear upside down in the camera.

A common use of pinhole photography is to capture the movement of the sun over a long period of time. This type of photography is called solargraphy. Pinhole photography is used for artistic reasons, but also for educational purposes to let pupils learn about, and experiment with, the basics of photography.

@karnamdpdurga you can learn more about pinhole camera from here.



Thanks, @Manpreetheersskp for a detailed reply! I was not aware of solargraphy earlier :learning: (:frowning_face: there is no emoticon for learning, can someone make new emoticons). Solargraphy sounds like an exciting and doable project! Do you think we can extend your viewer into a solargraphy instrument? Would be a fun long run project, once designed!

Also, the inverted image of the pinhole cameras reminds me of our eye! Do you know even we have inverted images on our retinas! :grin:



@karnamdpdurga, I had researched on solargraphy instrument :man_scientist:. And the conclusion is that we can make one solargraph but the solar eclipse viewer that i had made it can not be converted in to solargraph.I will try to make one solargraph. :thinking:

Here is the video from where we can take help to make it. :point_up_2:


Oh, yeah! :+1::+1:

When I was thinking of extending your viewer to solargraphy instrument, I was wondering how we could capture the light and let it leave a trace on the paper. Was thinking of using ways like someone marking with a pencil at fixed time intervals.

The video shows using photographic paper to do it, and it pretty cleanly ensures a dark space using coke tin. :impressive:

If you have easy access to the above material, please go ahead and try setting it up! Apparently, we need to permanently set it aside in a well-lit place for about 6 months! Any reason, why not all the 12 months? :thinking:

Also, as you work on this implementation, let us also think about some other solutions too… Let’s put on our thinking hats to find other instruments of tracking the sun’s trajectories. Maybe in our school grounds or terrace of our houses or apartments! We can do this exercise across the country (from Kashmir to Kanyakumari, from Arunachal to Dwarka), and see how the patterns are same or different. Looks like we are up to a large-scale project! :star-struck::star_struck:

Why don’t we start another chat-thread for the same, linking this thread?



But, then, we don’t see images as inverted!!! How? @karnamdpdurga


@Arunan, that is the magic! When I first learnt that the image on the retina is inverted, I started questioning everything about our world. Perhaps, we are all hanging from the earth like bats! :upside_down_face: :upside_down_face: I don’t know if all the animals have the same inverted image on retina! :thinking: I guess, we can take this up as a separate thread, getting into the technicalities of the neural processes, what do you think @Manpreetheersskp?

btw, @Manpreetheersskp are you working on the solargraphy instrument all alone, or working any in and around your home?

@Ashish_Pardeshi, we could think of extending the weather station to also include this, what do you think?



@karnamdpdurga First of all we can start a seperate thread today on getting into the technicalities of the neural processes. But in the solargraphy instrument I was unable to find out photographic paper :disappointed_relieved: if you have any suggestions about it to were to find it you can reply to me.



It’s all done by the brain.

The eye is just a sensor. Making sense of what is sensed is the job of the processor - the brain. In addition to inverting the image on the retina, the brain is also able to combine the images from the two eyes to give us the perception of depth.

In fact, this processing is not passive. That is, the brain does not just take the image from the eye and invert it. If the input to the eye is altered over a sufficiently long period of time, the brain is able to compensate for it. This is known as perceptual adaptation

you can learn more about perceptual adaptation

from the link :point_up_2:


@Manpreetheersskp, Sorry for the delay. The existing designs as you appear to take inspiration from, need some resources which we do not have access to. I do not have ready alternatives either! But, I believe lack of resources have always triggered human creativity and have been moments of inventions in history. So, I am very glad that we are stuck now. :grinning: :grinning:

I think in the spirit of continued exploration, let’s start reflecting on: what does the photographic paper do in the design? And what do we need to capture if we need to capture the Sun’s trajectory?
Some alternate ways could emerge! There are always sophisticated ways using photosensors and other mechatronic possibilities… But, let’s put on our creative hats, and think, if there are simpler ways using daily available objects! :thinking:

In fact, after your initial eclipse viewer, I was thinking on the lines of some pencil markings on a paper capturing the sun’s movement! but that requires manually marking. Now as I think, there could be one way using magnifying lens that we play with. If you have access to some magnifying lens… perhaps, by focusing onto a thick chart paper, sun rays could leave a trace (by faint burning)! What do you think? There could be other ways of keeping track of sun rays… may be using shadows!!

Let’s keep thinking… Lagey raho @Manpreetheersskp



I have created a new thread about this topic, let’s continue there.



@Manpreetheersskp, can you join in one of our chatshaalas that happen, every weekday? These are 1-2 hour webinars where we discuss and troubleshoot each others projects and learn.

There is a wider group of participants, and perhaps, we can get some breakthrough and support in taking this ahead! What do you think?



Yes, @karnamdpdurga I can join but when?


@Manpreetheersskp, this is something that normally happens every day from 330 pm. You can join from today if possible, there will be a lot of discussions about other projects as well, which you can engage with.

The details are as follows:

Link: https://webinar.hbcse.tifr.res.in/b/rs7-7hj-une

Date: 9th July, 2020

Timings: 03:30 pm to 05:00 pm

Tagging to keep you in loop @Ashish_Pardeshi @ravi312 @jtd