"Where is that"? As another class gasps at the inverted view of
the outside world. It takes getting a teacher to run around
outside, projected upside down on the screen in front of them to
convince them it is a live image. No web cam or projector, just a
2500-year-old optical projection.
What is it?
The camera obscura (Latin for 'darkened room') is the earliest
optical device and goes back over 2500 years. Originally images
were projected through a small hole but from around 1500AD onwards,
they began to use a lens.
Creating an obscura is cheap, easy and can be used at all levels
to introduce aspects of art, science, history and technology.
I have been teaching photography and pinhole photography for
over 20 years but over the past 5 or so years I have realised the
increasing lack of 'wonder' within modern technology. However
clever interactive smart boards and digital projectors are, I have
never seen their use result in a gasp of amazement from a class of
tech savvy primary children. Perhaps it is the lack of opportunity
for understanding in our ever-increasing 'auto' world, which
creates a barrier to comprehension.
Viewing a camera obscura projection does just this. Inspiring
wonder should be the bedrock of education.
Creating a camera obscura is cheap and simple. By simply
blacking out a room, positioning a lens and hanging up the
projection sheet you can create a giant 2m x 2m inverted colour
projection of the outside world 2500, years after Aristotle first
wrote "WWW, that's CWWL!"
It can help teach history; science; art and optics in a single
dynamic memorable fun filled lesson. The definitive contrast to
modern digital imaging and projection.
Obscuras work most effectively in a completely blacked out,
light tight room and work in both sunny and overcast conditions.
Blacking out a room can be done with pre cut cardboard, which can
be quickly placed into position with Velcro tape.
Creating a scenario.
Before you show a projection, cover the lens with some card and
light the room with a dim (red cycle) light to allow the students
eyes to get used to the dark. Whilst their eyes adjust you can tell
them all about how light works, how stone age men possibly first
noticed inverted images in their caves and how the gaps in a leaf
canopy have been projecting the image of the crescent moon onto the
forest floor for millions of years, then, whip the card cover off
the lens et voila! Instant wonder!
Initially you could get your students to attempt to draw the
inverted projection by using a card frame and tracing paper held in
a stand but there are many other experiments with light, which can
be performed in a light tight room involving prisms, lasers,
mirrors etc.
The instructions cover: Ancient Egypt and Ancient Greece, Isaac
Newton and the shadow of a hair, pinhole projections, slot imagery,
the use of concave mirrors, concave mirrors, prisms as well as
looking at digital versus optical projections.
The Glenfrome 'Dark den'.
I have always been a fan of removing the idea that 'complex'
subjects require older children to appreciate them, which is why I
leapt at the opportunity of adapting the reception years outdoor
den into an obscura. The process took about 20 minutes to
build and is used daily by the children in reception, especially by
my 4 year old daughter Rosa.
Although a white sheet is currently hung in the den it works
just as well with the children holding a sheet of white card to
find the focal point and the area that their friends are jumping
around outside, and more often than not trying to stand on their
heads! Holding a board with - THIS IS UPSIDE DOWN written back to
front also works well (although hopefully not too much of a
hindrance to jolly phonics!)
Instructions on how to make the obscura can be found on my
website or if you want to save yourself a trip to several shops, a
kit with instructions can also be purchased. 2500 years of wonder
for £1-00 a century!
Biography
Justin Quinnell is a freelance pinhole photographer and lecturer
from Bristol in the UK. His website www.pinholephotography.org has
information on creating camera obscuras and pinhole
photography.