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Here Comes the SunPart 1: Layer offset in After Effects
Recently Ive begun a project that will require an image of a sun to appear above a persons head. The sun will need to rotate, slowly at first, then progressively get faster and faster until it becomes a blur of light. To enhance the illusion that it is a ?realistic sun, light rays will be added. To complicate things the sun will have to grow in size over time, so the light rays will have to compensate.
My first thought was to begin with the actual Sun. Short of going out and burning my retinas (not to mention the CCD and internal workings of my PD-150), I decided to seek my sun images from a more practical source. A great resource for a lot of information about the Sun, as well as a great image library, is SOHO (http://sohowww.nascom.nasa.gov/) the project dedicated to exploring the Sun. A little exploration of the site will reveal that the people behind the project take daily images of the sun in a variety of spectral ranges.
While the EIT 195 (green) sun images are taken multiple times throughout the day (and thus would result in smoother motion), the EIT 304 (red) images, which work better for this project, are usually taken on a daily basis (more on that later). These images are archived on the site and even include high resolution (1024 x 1024) GIF files that you can freely download. A twenty minute or so download spree yielded me roughly 75 images (just a little over two seconds of video).
To save time during the massive download, I also didnt renumber the images, because they include the date information in the file, which is good enough for what I am goofing around with. There were a couple of problems with this approach. First, the files are Indexed GIF files meaning they are not RGB. Second, because of the number scheme used by SOHO, if you try to import the files as a regular image sequence in After Effects, After Effects will think a large number of files are missing (the dates 013103 and 020103 cause After Effects to think that there are 7000 images missing, which it will then fill with stand in color bars).
The first problem is easily remedied by creating a quick Convert to RGB action in Adobe Photoshop and applying the action to all of the images in my SOHO folder (visit the Adobe Photoshop forum on the WWUG, David Nagel will surely explain how to create an action that will work on a folder of files). The second problem is a little more complicated, because it would require having to renumber all of the images by hand. Ten images wouldnt be that big of a deal, 75 becomes a chore, but if you took the time to download 365 days worth of Sun images, renumbering would become a nightmare.
Related Keywords:SOHO, sun, sequence layers, offset layers, after effects, schleicher, tutorial
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