Astroblog: Stupid Mobile Phone Tricks

Sunday, July 22, 2007

Stupid Mobile Phone Tricks

In Animations of Venus I showed what could be done with an unguided 114 mm Newtonian and a cheap web cam. Inspired by DaveP, I tried out some mobile phone astrophotography. If you want a low cost digital camera, few come cheaper than the cameras in mobile phones these days. Some even come with 5 megapixel cameras (of course they are a bit more expensive).

EldestOne has some friends over in the evening, and wonder of wonders the sky wasn't cloudy, so I set up the 8" for them to look at the Moon. Afterwards, when we had watched Nerds FC and Dr. Who, I tried capturing the Moon on my mobile phone camera. The result can be seen above (click to the image to enlarge it). The image was taken by holding the phone up to my 12.5 mm eyepiece, and simply clicking. Not as good as this mobile phone image of the Moon, but not bad (it's not even in night mode). Compare it with DaveP's Moon shot. If I had done something clever like using rubber bands to attach the phone to the scope, or properly centred the image so there was no edge distortion, it might have been better.

This image was much harder. This is Jupiter. Jupiter is greatly overexposed, even with the standard mobile setting, but you can see 3 of Jupiter's Moons, two to the left and the horribly distorted blob to the right is Europa. Not as good as DaveP's image of Saturn, but not bad.

This was taken using my 6 mm eyepiece and was much harder. It took me ages to get Jupiter into the field of view of the camera. I had to ensure Jupiter was dead centre in the eyepiece, and even then it was hit or miss to come across it in the camera filed of view. I wasn't quite so careful in ensuring the camera was steady, as I was worried about losing the image (which had happened a few times already, with much frustrating hunting around). I actually took a darkframe, and subtracted it in the Gimp.

In both the Moon and Jupiter images, I had the focus set up so the image was focused for my eyes in the eyepiece, then just wacked the camera on and clicked the button (made rather easy by the camera/button layout on my mobile).

So there you have it, mobile phone astrophotography, see this site for some more images and hints. Get out there and get snapping (should work with binoculars too).

Labels: astrophotography, Jupiter, mobile Phone, Moon