Children can investigate whether rotational symmetry is more likely to occur when using this toy. This is where photographing real features is different from looking at a toy kaleidoscope where there is a tube, a triangular prism of mirrors and coloured pieces of plastic at the end. Saying this, the reverse challenge is to create an image which has rotational symmetry. In the photo below, you can use a mirror to clarify that the symmetry is indeed reflective rather than rotational. Photographing my dog gave the best illustration of the difference. But unless you target your feature carefully, it is unlikely to have rotational symmetry, even if the original feature has – as indicated by this lifebuoy station which has a rotational symmetry of 2. There will always be 3 lines of reflective symmetry. Also, there are more challenging activities to undertake which are probably suited to children in older classes.įor example, does the kaleidoscope app create photos which have rotational or reflective symmetry? This will really test a child’s peers of observation and understanding of rotational symmetry. For young children, this is the level I would be working at.Īs well as learning about photography and seeing features in a different way, other useful discussions may arise. With classes, group of children can have fun creating “pairs” of objects for others to match up or to play “snap” with. As I was at the beach, I went around photographing different features in a normal frame and a kaleidoscope one.Įven the most mundane features take on a new form and life when photographed through the kaleidoscope feature. Photo (#6) is an example of construction paper I photographed using a kaleidoscope made with front surface mirrors, and you can see that all of the reflected facets are sharp.I decided to undertake a very simple “Guess the Feature” activity. You can find outlets for this specialized type of mirror online by searching for front surface mirror. You must handle this kind of mirror gingerly because once you get a fingerprint on it, it is very difficult to remove without smudging or scratching the mirror. In fact, it’s very difficult to distinguish which of the facets are reflections and which one is the view straight through the kaleidoscope. A front surface mirror doesn’t have the protective glass surface, and therefore the image is not degraded. The way around this, if you want to spend the money, is to use front surface mirrors instead of the glass covered mirrors. This glass is not of optical quality, and looking through it at severe angles distorts and degrades the image. This happens because the mirrored surface we use is covered by glass (just like the typical bathroom mirror) to protect the delicate reflective surface. The surrounding facets are less sharp, and near the edges of the frame the quality of the image is significantly degraded. If you look at the kaleidoscopic images #1 through #5, you will see that there is a center triangular facet that looks very sharp. If you have a wider angle lens, that’s great. I would recommend using at least a 24mm lens (on a full frame sensor camera), or an 18mm lens on a camera with a smaller sensor. The number of facets in the resulting photos increases as the width of your lens increases. To take a picture, I simply put the lens of the camera inside the triangle of mirrors, as you see in (figure A). I used duct tape to hold the unit together, and voila!, a kaleidoscope was born. To construct the kaleidoscope, I simply stood the mirrors on their ends and arranged them in a triangle such that the mirrored surface was inside. I had them smooth the edges of the glass so it wasn’t so sharp (this is important because cut glass is razor sharp), and now it was much safer to handle. I went to a glass shop and asked them to cut three pieces of mirror measuring 6x12”. To take pictures, it’s necessary to add a third mirror to form a triangle. The cost is around $5-$10, and it can be put together in just a few minutes.Ĭommercially manufactured kaleidoscopes have two mirrors inside of them set as a “V”. Several years ago I figured out how to construct a kaleidoscope that would permit photography, and I’ve always had a lot of fun with it. I have long been intrigued with kaleidoscopic images, but it’s virtually impossible to photograph into a traditional kaleidoscope because the hole through which you look to see the beautiful designs is too small.
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