You can use your telescope to take stunning pictures of the moon, the planets and the stars. While many amateur astronomers believe astrophotography necessarily involves purchasing expensive cameras and tracking mounts, you do not have to spend a lot of money to begin photographing the night sky. You only need a webcam, a computer and your telescope to photograph bright objects such as the moon and planets. Attaching a webcam to your telescope allows you to document your astronomical observations and share them with friends and family.
Remove the lens from the webcam. Most webcams employ a threaded lens, so you should be able to remove the lens simply by unscrewing it. Disassemble the webcam by removing the casing if it does not use a threaded lens. Then remove the lens and reassemble it.
Cut the closed end off a plastic 35mm film canister to convert it into a telescope adaptor for your webcam. Most modern telescopes use eyepieces that are 1.25 inches in diameter. The diameter of the film canister happens to measure 1.25 inches as well, so it will fit perfectly into the telescope's focuser. Glue the modified film canister to your webcam where you removed the lens.
Plug the webcam's USB cable into an available port on your computer. Turn on the computer and launch the webcam's video capture software. Configure the software for astrophotography by setting the webcam to capture 20 frames per second and adjusting the gain settings to 75 per cent. Begin recording before inserting the webcam into the telescope's focuser.
Locate a bright object with the telescope, such as the moon or a planet. Center the object in the eyepiece's field of view and then remove the eyepiece from the focuser. Insert the modified webcam into the focuser. Tighten the lock on the side of the focuser to ensure that the webcam stays in place.
Look at the image being recorded by your webcam's video capture software to verify that the object is centred in the webcam's field of view. Adjust the telescope if necessary to re-centre the object. Focus the image with the telescope's focuser. Continue recording until you are satisfied that you have captured the object with your webcam.
Examine the recording frame by frame to select the clearest and brightest images. Export the still images with the webcam's video capture software by saving them as JPEG or BMP image files.
Use a webcam equipped with a CCD chip. CMOS-based webcams do not offer the brightness or resolution necessary for astrophotography. Inserting a Barlow lens between the telescope and the webcam will increase the magnification, and thus the size of the object being photographed.
Tips and warnings
- Use a webcam equipped with a CCD chip. CMOS-based webcams do not offer the brightness or resolution necessary for astrophotography.
- Inserting a Barlow lens between the telescope and the webcam will increase the magnification, and thus the size of the object being photographed.