NASA manual for photographing planets with your smartphone

Next week an expected astronomical event will occur: the alignment of six planets in the sky. New northern lights are also expected to occur in the coming weeks. Obviously, we all want to portray them in the best way possible, but It is not an easy task: light, distance and resolution (among other factors) work against us. How to photograph the sky with a smartphone then? Turning to experts like NASA.

The United States Space Agency has created an astrophotography guide… the “problem” is that it has 192 pages and we may not have enough time to read it. Astrophotography with smartphones is possible thanks to the great advancement of technology. They have different types of lenses, resolutions above 50 MP, programs to adapt exposure time, sensitivity (ISO) To which we could add online programs that allow us to easily edit the images.

NASA distinguishes three different photographic sections: photographing the stars, atmospheric events (such as the northern lights) and the planets. Let's go with the first of them. The Stars are one of the most complex targets to photograph with a cell phone due to the distance and poor light to record them. The first thing is to set the camera to infinity and program the highest sensitivity possible. Then you have to ensure that the camera is still, whether with a tripod or support. If we have a smart watch or other device that allows us to activate the camera, the better. That way we don't touch the camera when we have it in place.

“We must start with the bright and easily recognizable constellations – notes NASA -. Maybe the first images look very dark– Use a photo editor to change the Levels setting by moving the midpoint slider toward the white point.”

For their part, atmospheric phenomena, such as the northern lights, have their own tricks. Here the NASA recommends an exposure between one and 10 seconds and the ISO at 800. Again, the focus should be on infinity. We must also use a rigid structure and explore which option, in terms of time, gives us the best results.

As to the planets, the difficulties are other. At first glance they may appear bright and easy to photograph. A key is to use their brightness to our advantage and place them against a dark sky, to highlight them more. The problem is that the camera will see the planet as a bright spot and autofocus may not help much.

“One trick – notes the space agency manual – is to capture Venus (the brightest planet from Earth) on an illuminated horizon. As long as this horizon is far enough away, the phone's autofocus should lock on the horizonallowing you to take a photo of Venus in context.”

Alternatively, some phones offer a “focus lock” feature where you can point it at any distant horizon and lock focus on it. Mars and Jupiter may also become bright enough for many camera phones. The brightness of Mars is mostly mediocre, but at opposition it can increase considerably, even surpassing Jupiter to the position of the second brightest planet. Again, the recommendation is to place it over a dimly lit horizon.

The other option is to use a telescope and point the camera lens at the telescope's pre-focused eyepiece. This takes practice and a steady hand. It is a bit of “cheating” and not all of us have a telescope, but it is an option. Finally, NASA also recommends taking advantage of the fact that we are using a mobile phone to download applications specifically designed for this. These allow us not only to find the planets, they also provide us with the appropriate configurations. For iOS NightCam or 645 Pro, while for Android, Camera FV-5 and Open Camera.