Composite Time Lapse star trails

[mymoon]

Hi I am now quite proficient in taking star trails and taking time lapse of stars.

I came across this video which puzzles me in its execution; a combi of star trails and time lapse.

http://www.youtube.com/watch?v=eRJysFYWQqo&NR=1

from t=0.00 to 0.04 sec it is strictly time lapse but from t=0.04 sec onwards shows the rotation of the earth.

Care to share how it is done.

another example is http://www.youtube.com/watch?v=ANAmiuAkyGQ&feature=fvsr

aziz

[iceman]

Hi Aziz

I did the first video you linked above.

I'll tell you how I did it, though there's probably other ways to do it too.

I use startrails (http://www.startrails.de) software to create my startrail images and also used it to create the timelapse, using the 'video' button.

So the sequence started as a timelapse video, then had the star trail composite. You'll notice when you use 'startrails' to create a startrail image, it adds each image to the final as it goes.
I simply 'recorded the portion of the screen' as startrails was creating the final image. I can't remember the software I used, but it was freeware and was one of the types of software that you'd use for training videos etc, where you can record a portion of the screen.

So I had the timelapse video, then a video of startrails building up the star trails image, and the final star trails image. I simply combined all of them using Windows Movie Maker.

I'm sure you could use other programs to achieve the same effect - one example would be using photoshop actions to reveal each layer of an image one at a time to create the star trails image, and then again using screen-recording software to create a video as it does it.

I'd be interested to hear of any other software that could do it.

I hope I've explained it well enough. Let me know if you have any questions.

[Rayleigh]

Just had a quick look at your photo gallery Mike - they are all beautiful - sandscapes and all.

[iceman]

Thanks Rayleigh!