Olivia, Jack and Papa Build a Camera Obscura Out of a Bedroom!

Last week, our granddaughter Harper stayed with us (see previous post). This week, it is her brother Jack and cousin Olivia. They are also attending Dallas Parks & Recreation Outdoor Adventure Camp during the day and in the evening we're having other adventures with them. While Harper's camp was focused on photography, this week the focus at camp is on archery. Linda and I don't have a lot of archery experience so our evening adventures are things that are more in our wheelhouse. One of those is photography. :-)

Optics: the principle of the camera obscura.
Engraving, 1752. Wellcome Collection

Tuesday evening, the project was to build a camera obscura. If you aren't familiar with the term, it's an ancient discovery that by having a darkened room with a small hole in a wall or window, a view of the outside scene is projected onto the opposite wall. The image is inverted (sky below, ground above) and in practice is pretty dim. In this digital age, as an alternative to sitting for a long period for your eyes to become dark-adapted enough to see the image, you can capture it with a camera capable of taking long-exposure photographs. 

 There are various tutorials available online on how to create a camera obscura out of a room in your house and capture the image on a camera. We used this one from the George Eastman Museum. It's very clear and easy to follow.  

Outside view of Camera Obscura

In choosing a room to use, we went with the master bedroom. Not only does it have a window with a reasonably interesting view (our backyard) but there is just that one window and although the room has glass doors facing our patio, there is a storm shutter that (mostly) blocks all the light from it.

While the kids were at camp, I masked off the outside of the window which was simpler than trying to tape plastic over the inside. Using cardboard, a black tarp, some plastic bags and gaffer's tape it was pretty quick and easy to block out all light from the window. It ain't pretty, but it's functional. 

The next step was to make lens boards with pinhole lenses. After the kids got home, we sat down to fashion them from cardboard, washers and gaffer's tape. Olivia's has a smaller hole (aperture) which would potentially give a sharper image but requiring much longer exposures; the aperture on Jack's was a bit bigger. 

Next, we finished prepping the bedroom. Initially, we just used towels on the floor to block light coming in through doors and a towel hung over the bathroom door since it had a bigger gap, let more light through. Later, we tried painter's tape. 

As I mentioned, the image in even a darkened room is a bit dim. Given that it takes about a half-hour for our eyes to become dark-adapted after being in a brightly lit room, it wasn't really practical to stay locked up in the bedroom for that long given the kids still needed to get showers after a hot day at camp and we hadn't yet had dinner. Not to mention the impatience of a 12 year-old and a 10 year-old. :-D

Instead, I pulled out my Nikon D750 with a wide angle lens and we captured the view with exposures ranging from 30 to 55 seconds. Of the images below, the first was taken before dinner while it was still pretty bright outdoors; you can see there is still direct sunlight on the fence. It was also taken with Jack's pinhole lens with it's slightly larger aperture so the image is nice and bright. The other two were taken after dinner so it was getting a bit darker outside; there is only a sliver of direct sunlight on the fence. The first one is with Olivia's pinhole lens, the second with Jack's. 

These images have been inverted vertically to emphasize the "normal" view of the backyard but that means everything in the room is upside down with the bed on top (lit blue by the sky) and the ceiling fan down "in the grass". Also, notice that the entire inside of the room is the "camera". Pretty cool!

Shot early evening with larger aperture

Shot later in evening with smaller aperture

Shot later in evening with larger aperture

We have a few other ideas for the camera obscura, interesting alternatives to explore, so stay tuned... we might have more to share soon!

As always, click on an image to see it large.