Tag Archives: Binocular

Raspberry Pi Goes Binocular

This project uses the popular single board computer, the Raspberry Pi (RBPi) and a spare pair of binoculars to view and take pictures. The LCD on the RBPi is touch enabled to make it easy to capture the images.

To start with, you will need the appropriate Operating System for the RBPi. Download the Wheezy Raspbian OS from the Adafruit site, which will make it easy to interface the 2.8” TFT LCD with a capacitive touchscreen from Adafruit. Once download is complete, unzip the image and install it on the SD card. For the RBPi, you will need the Pi camera with its cable.

Make a suitable arrangement to mount the RBPi and LCD securely on the binoculars and place the camera on one of the eyepieces. This will tell you if the default cable that came with the camera is enough for the purpose or you need to order a longer one. A Wi-Fi dongle (USB type) makes the entire arrangement suitable for transmitting images over the net. In the absence of a Wi-Fi dongle, connect the RBPi to your network using an Ethernet cable.

To configure the RBPi, initially you may have to start with the Raspberry Pi Software Configuration Tool, by logging in and running the command “sudo raspi-config.” This will allow you to set the language, time zone, and keyboard layout according to preference. Additionally, you will also be able to enable the camera, set up the IP address, and the Wi-Fi credentials, which the RBPi will use to communicate.

You can mount the RBPi over the camera in a number of ways, depending on the material available. It is possible to do this with stiff cardboard, thin plywood, and tape. Measure the binoculars and the RBPi to make a suitable cutout in the cardboard. This may require using jigsaw, drill, or laser cutters. If you have access to a 3-D printer, take more accurate measurements, make a suitable image using engineering software, and print a template. Whatever the method of mounting, make sure the RBPi is secure and does not fall over.

Power up the RBPi and the camera and you should be able to see the image on the LCD screen. Place the camera on one of the eyepieces so that light passes through the binoculars and falls on the camera lens. Adjust the position of the camera until you see a well-defined circle on the screen. Now secure the camera to the eyepiece with tape.

For transportability, use a rechargeable battery pack to power the RBPi. For instance, a 2300 mAh battery pack will allow around two hours of operation. To prevent corruption of the SD card, program the RBPi for safe shutdown well before the two hours is over. If the battery pack is also mounted on the binoculars, the total weight may increase, making it difficult to hold and adjust. It might help to have the battery pack on a long enough USB cable, to allow the pack to be kept in the pocket.

It is necessary to connect the RBPi to the Internet if you want the images properly time-stamped. As the RBPi does not have an internal clock, it has to synchronize the date and time with the Internet connection.