Astrophotography is a difficult skill to learn and astronomers wanting to get perfect pictures of the night sky can experience some basic problems.
• The digital camera picking up interference from light sources other than starlight
• Stars emitting dim lights. This often makes it impossible for the astro-photographers to capture bright and high-quality images.
• The stars move across the sky with the rotation of the earth.
• Most digital cameras have a limited exposure time of up to 15 to 30 seconds
By adding in a microcontroller, such as Arduino, to control the functions and motion of the camera, many of these problems can be eliminated.
1. Photo-stacking technique
Photo-stacking technique produces detailed pictures of star fields and related phenomena like galaxies. You don’t need to use a telescope with the stacking method. Stacking images increases the amount of detail captured and the camera and the tracking motors are controlled remotely by an Arduino board.
|Image is licensed under CC Attribution|
With this method, you need to take many images of the sky and use a computer program to deal with the removal of noise. The photos are downloaded onto the computer and any unwanted or unnecessary image artifacts are removed, such as airplanes or clouds using Rot and Stack or Deep Sky Stacker software which will align all photos taken to ensure that the stars are at the same place before doing dark field subtractions and saving of the aligned copies so you can open them in layers.
Stacking all the pictures essentially means that by taking the mean values of each pixel, the resulting photo has all the details without any of the visual noise.
2. Building an Equatorial mount for long exposure photos
Using a tripod to get long photographic exposures of the stars is not very effective as any significant exposure length leads to star trails, smearing the light from the stars in an elegant (but unwanted) curve on the photo. To avoid this, you need to use a special type of mount that can spin with the earth, keeping the stars still and in sharp focus. An equatorial mount can be mounted on a tripod and with the careful programming of the controller for the motors, will allow your camera to track across the sky and get the details that are often more difficult to capture, like the Milky Way.
As the mount needs to have power throughout the entire exposure, I’ve set mine up with an uninterruptible power supply so I don’t have to babysit the camera all night and don’t have to worry about any potential power failures. As you can only get one photo per night with this technique, each exposure counts. With that in mind also check the weather forecast for the entire night and only set up the rig when there are clear skies all night. Not only will you keep any rain off your equipment, but you won’t get a photo ruined by a blurry smudge of the cloud.
3. The Auroral indicator
The Auroral indicator gives a visual warning of when the Northern Lights are likely to be visible.
The kit for the prediction indicator has the following three main components:
• PHP web scraping script
• Processing script
• Arduino script
It has an LED display that shows the current level of Auroral activity, a PHP Web scraping script gathers the information from the Costello geomagnetic activity index and the processing script allows the Arduino to use a system of different colored lights to simply display the information: red for high activity, green for low activity, white for prior warning, and blue for moderate. The simplicity of Arduino comes into its own on builds like this, bringing the project within the reach of an enthusiastic amateur.
The endless uses for a small, power control unit has given people a reason to learn the Arduino software, as well as electronics, which enable them to build and control almost anything that they can think of.
Watch the video below to know more:
Christopher Parkinson’s interest in electronics stems from an early age, I remember watching my father using a multimeter to test my Scaletrix which had stopped working. At that time this was the most fantastic thing I had ever seen a bear in mind I was 6 and so very easily impressed. I went on to study microprocessor design theory before working for a company repairing mobile phones.
This article is contributed by Christopher and posted by Rizwan Ahmad Author and founder of cyberockk.com, He is a tech blogger from India and he loves to share his thoughts by writing articles on this site to the different topics related to technology world,