BBC Sky at Night Magazine

Planetary cameras

Capture fine detail and beat atmospheri­c turbulence by shooting hundreds of frames

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If you wish to capture celestial bodies within our own Solar System, there are cameras dedicated to the task. Planetary cameras are video cameras configured to perform at high frame rates, often hundreds of frames per second. Planets are the astronomy targets most susceptibl­e to atmospheri­c ‘seeing’ – conditions caused by weather and pollution. Poor seeing conditions are obvious; when capturing video or looking through an eyepiece, the planet will wobble and dance around the field of view. On nights of good seeing, the object is more stable and detailed.

A standard camera’s frame capture will be sluggish for these fast-moving distortion­s in the atmosphere, and images will be soft or blurry. High-frame-rate captures, however, cut through the atmospheri­c disturbanc­e and sharpen planetary images. For the same reason, they’re great for capturing the Moon.

Planetary cameras can’t be used on their own and must be controlled via software on a computer. They often come with manufactur­er-specific software, but other free examples include SharpCap and FireCaptur­e, which have additional features such as selecting a ‘region of interest’, which allows for quicker capture speeds.

Rather than the hours of long exposures required for deep-sky images, it takes minutes to capture planetary videos, thanks to the high frame rates. Ten minutes of shooting will provide many thousands of frames, of which some will (hopefully) have cut through seeing at the right time. AutoStakke­rt! and RegiStax can stack and process the video into a single image.

Because planets are small, they appear tiny in our field of view, even with long-focal-length telescopes, meaning that a 1.5x or 2x Barlow lens is often required to magnify the planet and provide the best views. ▶

 ?? ?? ▲ A dedicated planetary camera shoots lots of short-exposure frames quickly
▶ Because it’s speedy, you can snatch frames of the planets when there’s a break in the clouds
Once stacked, images show very low noise and plenty of pin-sharp details
▲ A dedicated planetary camera shoots lots of short-exposure frames quickly ▶ Because it’s speedy, you can snatch frames of the planets when there’s a break in the clouds Once stacked, images show very low noise and plenty of pin-sharp details
 ?? ??  Software like SharpCap, shown here in Live View, will align and stack your video frames
 Software like SharpCap, shown here in Live View, will align and stack your video frames

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