Movies

With one exception (the movie of the total solar eclipse in 2006) the moving images on other pages of the gallery are actually animations i.e. they are constructed manually from individual images taken at different times. This is because the file size of genuine movies (like those one would take with a camcorder) are very large and thus the medium is somewhat impractical. Furthermore, while animations will automatically display within the text of web pages, movies have to use an external player like Windows Media Player or Real Player and so must be clicked on to be seen.

The file size objection was dramatically overturned when I found out about the RAD Video Tools application that I used to vastly reduce the size of the total eclipse movie. Applying the same technique to planetary movies worked the same magic (at least to those having lots of black "sky", anyway) so they are now of a much more reasonable size! The image quality isn't quite as good as the originals but I think it's a trade-off worth making so the movies can be seen. They must still use an external player, but as most PC's will have one of these this didn't seem a reason not to have them on the website.

The first one is of the close conjunction between Mercury and Venus on 27th July 2005. The size of the planetary images is "as taken" and gives an excellent impression of how I actually saw them on the computer screen. The speed of movement is also "true", but slightly jerky as I have reduced the frame rate to further decrease the file size. What is also very apparent is the fact that the images change quite a lot between frames - this is not my fault this time but rather an effect of the Earth's atmosphere which randomly distorts the images. This makes taking still images something of a lottery, hence my use of the technique of stacking up images to improve the final result. Even on this movie though, it is obvious that Venus is not fully illuminated.

Conjunction of Mercury and Venus

The second one is of Mars on 31st August 2003, near the time of its closest approach to Earth for a very long time. The size of the planetary image is a factor of four larger than Mercury & Venus in order to show the surface detail better: the movie was taken at twice the resolution originally and then further expanded during the conversion process. The movement is much more jerky than for the conjunction as taking at twice the resolution has the unfortunate side-effect of dropping frames (I must get a faster laptop!). The image distortion is also more obvious than for Mercury/Venus as there are more features to concentrate on. This makes my comment that the best still shot I obtained was "one in a thousand" much more believable! The polar cap and Syrtis Major are easily visible even on these images though.

Mars at near approach

Finally, a version of the movie of the 2006 total solar eclipse taken with the digital camera. The one I converted for more general use (accessible from the eclipse pages) had to set the balance between size and quality rather towards size so I thought it would be good to make another version with improved quality. The file size of this one is over 30Mbytes, so even on broadband the download will be a bit of a wait, but I think the extra quality will make it worthwhile - see what you think!

Total Solar Eclipse