Time lapse - But with trailing stars

[tsk1979]

I am using avisynth imagesource for my time lapses.
However I want to achieve the trailing stars effect
Similar to what you see after 22s in this video
Please help?
How to overlay last "x" frames on the current frame. So video frame rate and duration is same, but you get trailing

[poisondeathray]

I don't see the video link

[tsk1979]

As I am a newbie I think it got removed
Try this one

I used Temporalsoften but it does not work the way I had hoped it would!

http://www.youtube.com/watch?v=oLd1gpVa5TY

[racer-x]

Looks like they were shot using "bulb exposure" very long shutter speeds. I'm not sure you can create the effect as well in post using short shutter speeds............

[tsk1979]

Looks like they were shot using "bulb exposure" very long shutter speeds. I'm not sure you can create the effect as well in post using short shutter speeds............

You can see many videos on youtube where shutter speeds used are less than 30 seconds. Video continues normally and then starts trailing,
Here is an adobe after effects tutorial
http://www.youtube.com/watch?v=L9lbs6Pxy0o

[jagabo]

Merge(SelectEven(),SelectOdd()) several times in a row. If the stars move more than a pixel between frames you'll get a trail of dots, not a continuous trail. And you'll probably find the stars dim too much. The latter is easily fixed by adjusting the contrast after each Merge().

Another possibility is Overlay(SelectEven(),SelectOdd(), mode="add") several times in a row.

Maybe you should provide a hundred or so sample images.

[racer-x]

I suppose you could overlay say 5 ~ 10 frames in photoshop or Paint.NET (free) and reduce the opacity of the upper layers to expose the stars, then flatten and export as a single frame. You can then duplicate as needed to keep up with the video.

Just an idea, as I have never done that before.........

[poisondeathray]

There is a function called clipblend() by StainlessS that will do something similar to the post plugins in after effects. You an specify the # previous frames to blend
http://forum.doom9.org/showthread.php?t=168048

Depending on your shot composition you might have to mask out the foreground (in your example, the foreground wasn't blended in the same manner as the starrs) . You can do that with a static mask done in a photo editor (e.g. gimp, photoshop) and overlay() in avisynth . Obviously if your shot was only of the sky, then it wouldn't matter

eg.
Overlay(base, filtered_overlay, mask)

You might have to adjust the clip depending on the timing of your exposures (eg. if they are too close together, you won't get the intended effect), e.g you might have to use something like SelectEvery with some interval to pick every "nth" frame

If you post an unfiltered example , someone might give you some more concrete suggestions

[Noahtuck]

If you read his description it say's,

Check out my site and instructions on how to make your own star trails photos: www.liquidinplastic.com (click how to for the guide)

http://www.liquidinplastic.com/2008/06/startrails/

[tsk1979]

If you read his description it say's,

Check out my site and instructions on how to make your own star trails photos: www.liquidinplastic.com (click how to for the guide)

http://www.liquidinplastic.com/2008/06/startrails/

Nope, I do not want to shoot star trails. I shot <30s exposures to get stars moving. Now I want to use an effect similar to cc time blend plugin in after effects

[tsk1979]

I used the plugin ClipBlend
It gives a similar effect, but creates a "Blur".
I am looking to replicate CC Time blend in avisynth
http://www.youtube.com/watch?v=3efz1cZT4zI

[racer-x]

Nope, I do not want to shoot star trails. I shot <30s exposures to get stars moving. Now I want to use an effect similar to cc time blend plugin in after effects

Then you do need to look at that guide because it is exactly what you are trying to do...................

http://www.liquidinplastic.com/2008/06/startrails/


Very similar to what I suggested but a lot more automated. I downloaded the program, maybe I'll try it out when I have some time to shoot stars.

[mike20021969]

I want to achieve the trailing stars effect

This might help: http://www.diyphotography.net/your-complete-guide-for-photographing-star-trails

[tsk1979]

I want to achieve the trailing stars effect

This might help: http://www.diyphotography.net/your-complete-guide-for-photographing-star-trails

Please read my post. I do not want to shoot star trails. I want to shoot normal <30s shots, and then start trailing in video. I see many videos where every frame "adds" to the previous. So it keeps filling up If you see these videos I have posted you will see even airplane trails are set.
This effect is CC time blend in adobe photo shop. I need CC time blend equivalent for avisynth

[smrpix]

I want to shoot normal <30s shots

What kind of camera and shutter speeds are you using to make that work?

Also, CC time blend exists for After Effects, it may be worth downloading the free trial if this is a one-off.

[poisondeathray]

One almost functional equivalent in avisynth to CC Time Blend FX in AE would be to use script clip from gavino

Since you didn't provide a sample, I chose a random video source example (I choose between ~ 00:50:00 - 00:60:00) . You might have to adjust the parameters slightly for your video
http://www.youtube.com/watch?v=opydr6RwaY4

FFVideoSource("Timelapse movie The Alps -- part II (night) (HD).mp4")
Trim(1280,1480) 
main=last

b=blankclip(main)
ScriptClip("""
  b = b.Loop(2,0,0).Overlay(last, mode="lighten")
  return b
""")

[tsk1979]

I want to shoot normal <30s shots

What kind of camera and shutter speeds are you using to make that work?

Also, CC time blend exists for After Effects, it may be worth downloading the free trial if this is a one-off.

i am using high ISO (3200) at F2.8 11mm with a D7000
Have done a few time lapses. I saw some videos where the trail effect was done using CC Time blend. So I am really curious if some similar effect exists in avisynth. From what I could gather, with the use of plugins and scripts you can match everything the sony vegas or Adobe after effects can do

[tsk1979]

One almost functional equivalent in avisynth to CC Time Blend FX in AE would be to use script clip from gavino

Since you didn't provide a sample, I chose a random video source example (I choose between ~ 00:50:00 - 00:60:00) . You might have to adjust the parameters slightly for your video
http://www.youtube.com/watch?v=opydr6RwaY4

FFVideoSource("Timelapse movie The Alps -- part II (night) (HD).mp4")
Trim(1280,1480) 
main=last

b=blankclip(main)
ScriptClip("""
  b = b.Loop(2,0,0).Overlay(last, mode="lighten")
  return b
""")

Perrrrrrrrrrrrrrfect!
Thanks!!!
Can you please explain what does blankclip do with (main) as argument?

Here is my script line to load all my images (1-129)
At 10fps its a 12.9 seconds long clip


S1=ImageSource("Filename-%d.jpg", 1, 129, 10).Lanczos4Resize(1920,1080)

[poisondeathray]

Can you please explain what does blankclip do with (main) as argument?

Here is my script line to load all my images (1-129)
At 10fps its a 12.9 seconds long clip


S1=ImageSource("Filename-%d.jpg", 1, 129, 10).Lanczos4Resize(1920,1080)

blankclip(main) produces a blank video the same characteristics as "main" (same fps, dimensions, duration etc....)

You would use blankclip(S1)

[tsk1979]

Should it be this?
Gives me syntax error

S1=ImageSource("...converted\A-%d.jpg", 1, 129, 10).Lanczos4Resize(1920,1080).ConvertToRGB

b=blankclip(S1)

ScriptClip("""
  b = b.Loop(2,0,0).Overlay(S1, mode="lighten")
  return b
""")

[poisondeathray]

Format it the same way as above

ImageSource("...converted\A-%d.jpg", 1, 129, 10)
Lanczos4Resize(1920,1080)
#ConvertToRGB
S1=last

b=blankclip(s1)
ScriptClip("""
  b = b.Loop(2,0,0).Overlay(last, mode="lighten")
  return b
""")

You probably don't need ConvertToRGB, becuase ImageSource() will return RGB from a jpeg sequence

[racer-x]

Way to go Poisondeathray.............!

My test example produced interesting results, even the clouds have trails.

[El Heggunte]

Way to go Poisondeathray.............!

My test example produced interesting results, even the clouds have trails.

lol Lol LOL

And speaking of trails, ...

[poisondeathray]

lol lol lol :d

and speaking of trails, ...

epic johnny cage shadow kick!!!!!

[tsk1979]

@poisondeathray! Thanks a lot for this!
I went through the documentation of ScriptClip but could not figure out how the script works.
Can you explain how it works, and how to use it in different scenarios
For example my video script has
S1 = ....
S2 = ....
S3 =...

And so on
Then I create
Dissolve(S1,S2...) etc.,
What if I want to create a S1_trail copy in my mega script?

When I saw S1=avisource(...) what does "last" variable contain?

[jagabo]

For example my video script has
S1 = ....
S2 = ....
S3 =...

And so on
Then I create
Dissolve(S1,S2...) etc.,
What if I want to create a S1_trail copy in my mega script?

Run the trail code on just s1, then Dissolve() or add (+) with the other clips.

s1 = ...
s2 = ...
s3 = ...

last=s1
b=blankclip(last)
s1trails=ScriptClip("""
  b = b.Loop(2,0,0).Overlay(last, mode="lighten")
  return b
""")

Dissolve(s1trails, s2, 15)
return(last+s3)

When I saw S1=avisource(...) what does "last" variable contain?

Any time you don't explicitely name a clip the name "last" is implied. So a sequence like:

AviSource("filename.avi")
Reverse()

is the equivalent of

last = AviSource("filename.avi")
last = Reverse(last)

[jagabo]

Here's a variation on the trails method.

function StarTrails(clip vid, int depth)
{
  vid = Overlay(vid.SelectEven(), vid.SelectOdd(), mode="lighten")
  depth = depth - 1
  depth > 0 ? StarTrails(vid, depth) : vid
}

ffVideoSource("Timelapse movie_ The Alps -- part II (night).mp4").Trim(620,1920)

v1=last
v2=Trim(last,6,0)
v3=Trim(last,13,0)
v4=Trim(last,19,0)
v5=Trim(last,26,0)

Interleave(StarTrails(v1,5),StarTrails(v2,5),StarTrails(v3,5),StarTrails(v4,5),StarTrails(v5,5))
AssumeFPS(25)

[tsk1979]

Here's a variation on the trails method.

function StarTrails(clip vid, int depth)
{
  vid = Overlay(vid.SelectEven(), vid.SelectOdd(), mode="lighten")
  depth = depth - 1
  depth > 0 ? StarTrails(vid, depth) : vid
}

ffVideoSource("Timelapse movie_ The Alps -- part II (night).mp4").Trim(620,1920)

v1=last
v2=Trim(last,6,0)
v3=Trim(last,13,0)
v4=Trim(last,19,0)
v5=Trim(last,26,0)

Interleave(StarTrails(v1,5),StarTrails(v2,5),StarTrails(v3,5),StarTrails(v4,5),StarTrails(v5,5))
AssumeFPS(25)

I think I will try out your method in my script as ScripClip is causing crash (access error) for me.