How to create time lapse video using a webcam

Simple Time-Lapse

Time-lapse animations have always fascinated me. With a time-lapse you can make things visible to the human eye that are normally happening too slow. The movement of stars in the sky or the process of putting up a house are very interesting to look at when the clock has been accelerated.

Apart form creating time-lapse animations using my own pictures I also found it worthwhile to create them from web-cam images. A webcam near the place I live provides images of quite high resolution. With the little script below, I was able to create this video: Fog over Dornbirn

I found that for videos that include clouds it is ok to take a frame every 5 seconds or so. As I don’t have the time and patience to save the webcam images manually, I created this bash script which was improved by Jürgen Hofer subsequently:

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Monster Sunspot AR2192

Today I had the opportunity to see and photograph the giant sunspot Active Region 2192, it already has rotated a bit away from our direction, so the probability of a massive solar storm with possible damage to space and other infrastructure is reduced.

Full disc view of sunspot AR2192

Detail of the image above:

Closeup of Sunspot AR2192


The images were taken with a Nikon D7000 camera using a Astro-Professional ED80 f/7 doublet refractor. A Baader solar filter ND3.8 was used for filtering the sunlight.

Creating Double Page JPEG images from PDF

While in the process of making a photobook in Lightroom I wanted to review the book before actually ordering it. For this I wanted to have the pages in JPEG format instead of one big PDF.

It turns out that with ghostscript one can easily extract the images.

I am using cygwin on a Windows 7 64 Bit operating system to work with ImageMagick, Ghostview and the like.

But before I was able to use ghostscript I had to fix this error I was getting about the font Arial.ttf not being found, after some research I found that creating the missing directories and adding a link to the font in the Windows directory fixes that issue:

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Bright night, bright meteor

With the so-called super-moon shining brightly outside the chances of successful meteor observations are pretty low due to the light of the moon washing out the fainter stars and of course meteors too!

But as the weather prospect for the next few nights is pathetic I set up the camera and took 434 shots using my Nikon D7000 with the Samyang (Rokinon, Walimex) 14mm f/2.8 camera at f/2.8, 2,5s and ISO3200. One of the frames actually captured a quite bright meteor:


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Colorful Moondogs

When I went outside this evening to check if the sky is clear enough to do some meteor photography of the Perseid meteor shower I noticed that the moon was accompanied by two colorful moondogs (parhelia). Bits of the 22° Halo are also visible.