Hey guys, I have a question about how to make slow motion look "smooth". I was working with some clips I shot the other day and when I slowed it down the footage seems to shutter. I am using a Canon XL-2. I was shooting at 60i and my shutter speed was set to 120. I am editing in FCE. I reduced the speed of the clips by 50%. The footage looks good but it seems to flicker or shutter. Is there a way to make slow motion smoother and more fluid? Thanks for any input or advice.
cinematography Slow Motion Question
- Thread starter Jones23
- Start date
Yes, when you slow it down you need something to interpolate the frames. I personally use AfterEffects.
Here's an old article talking about slow motion, 60i and even references your XL2 (at 1/120 shutter):
http://rarevision.com/v1/articles/slow_motion.php
Here's an old article talking about slow motion, 60i and even references your XL2 (at 1/120 shutter):
http://rarevision.com/v1/articles/slow_motion.php
Last edited:
I have just the thing for you. There is a simple trick in FCP to use each field as an individual frame and get great 50% slow mo from interlaced footage.
Essentially, you layer the clip over itself, setting each copy to 50%. Then apply a "blink" filter to the top layer (from the "video" filters on the effects menu). You'll want to blink 1 on and 1 off, so you get every other frame from the top layer of video. Now deinterlace the top layer and select either top or bottom and deinterlace the bottom layer and select the opposite. Now, if you selected the correct field order, you should have perfect slow-mo. If you picked the wrong (top/bottom) field, you'll need to invert your selections on both layers.
Essentially, you layer the clip over itself, setting each copy to 50%. Then apply a "blink" filter to the top layer (from the "video" filters on the effects menu). You'll want to blink 1 on and 1 off, so you get every other frame from the top layer of video. Now deinterlace the top layer and select either top or bottom and deinterlace the bottom layer and select the opposite. Now, if you selected the correct field order, you should have perfect slow-mo. If you picked the wrong (top/bottom) field, you'll need to invert your selections on both layers.
I have an apple script floating around here somewhere that will take exported image sequences and turn them into slowmo. Here's what I've written in the past:
me said:In Final Cut (only thing I've tested with):
1. Place your clip on a timeline (I like to make a new sequence to work with clips).
2. Double click the clip to bring it up in the viewer window
3. Apply the deinterlace filter (I think it's in the Video filter/Video subfolders)
4. Click the filters tab in the viewer window
5. Pull the Field pull-down Menu to Upper(Odd)
6. Render the clip (select and hit apple(command)-R)
7. Pull down the File > Export > Using Quicktime Conversion...
8. Pull down the Format pull-down menu to Image Sequence
9. Under options... right next to it, select an image format (prefereably something that doesn't compress in a lossy manner - TIFF is a good choice)
10. Under the Options in there, Best depth and none for compression.
11. Fit the naming to the convention called for in the script (when you start up the script, it'll show you the naming convention)
12. save the sequence to a new folder on the desktop
13. repeat steps 5-11 with Lower(Even) fields selected saving to the same folder as before
14. Hide Final Cut (under the final cut menu)
15. find the folder you've created on the desktop and duplicate it (cmd-d - always work on a backup)
16. run the script and select the backup folder you've just created (for real fun, keep the folder window open while you run it)
17. when the script stops, go back into final cut
18. Under Final Cut > User Preferences > Editing > Still/Freeze Duration = 00:00:00:01
19. Create a new sequence (or just delete the clip from the timeline and use the one you were using before)
20. In the project window, ctrl-click (right-click) and import > folders
21. Select the duplicate folder and let FC do its thing.
22. open the new bin (folder) that is created and select all (cmd-a)
23. drag the series of pix to the timeline...they should propogate in order
24. Export again as Quicktime so you can have a clip that doesn't have to re-render 1000 images with every change
25. Import the resulting QT file and use as you would any other movie clip.
I tried making a plug in that would do this automagically, but it needed to be a double pass operation, and I couldn't figure that part out...so this clunky process is what I have to offer.
Results:
http://www.yafiunderground.com/Video/shutter_test.mov
Here is the script:
http/www.yafiunderground.com/Files/Deinterlace_slowmo.app.zip
But Knightly, you can do exactly the same thing without exporting and get exactly the same result.
OK, you want it in cookbook style, here goes ...
1) drag your interlaced clip into the timeline and set it's speed to 50%
2) add a deinterlace filter to the clip
3) option drag the clip to the layer immediately above it (don't time-shift it and release the mouse before releasing the option key to avoid shifting the other layers)
4) add a blink filter to the top layer and set the blink to 1 on, 1 off
5) set the top layer's deinterlace filter to lower field
6) set bottom layer's deinterlace filter to upper field
Render and play. If the motion goes forward and backward, repeat steps 5 and 6, but reverse the field selections so the top clip uses the upper field and the bottom clip uses the lower field.
It always takes me longer to verify the field order than it does to actually set this up. I can perform these 6 steps in about 11.7 seconds (not including render time).
1) drag your interlaced clip into the timeline and set it's speed to 50%
2) add a deinterlace filter to the clip
3) option drag the clip to the layer immediately above it (don't time-shift it and release the mouse before releasing the option key to avoid shifting the other layers)
4) add a blink filter to the top layer and set the blink to 1 on, 1 off
5) set the top layer's deinterlace filter to lower field
6) set bottom layer's deinterlace filter to upper field
Render and play. If the motion goes forward and backward, repeat steps 5 and 6, but reverse the field selections so the top clip uses the upper field and the bottom clip uses the lower field.
It always takes me longer to verify the field order than it does to actually set this up. I can perform these 6 steps in about 11.7 seconds (not including render time).
I should add, that you probably don't need or want frame blending if you are using discrete fields for slow motion (50% speed) as described above. Frame blending will probably mess up the perfect slow motion created when 60 fields are spread out to 60 full frames.
Here's another sample video. The balloons make us look goofy (I'm in the gray sweatshirt), but keep in mind these are competition sabres and the game has been modified to a head-only target area. We play hard with one another 
[QT]http://yafiunderground.com/Video/slomo.mov[/QT]
[QT]http://yafiunderground.com/Video/slomo.mov[/QT]