Experimenting with slow-motion video on my standard Pixel 6

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DeltaVee

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About a year ago or so, my ancient nexus 6 started to wonk out on me so I got a Pixel 6. I discovered that it had slow motion and time lapse video capabilities. At our last official CMASS launch last year in November it occurred to me to actually take a few slow motion videos!

A few interesting features of the video (when replaying on the phone) is that you can tell the video when to play at normal speed and when to play in slow motion... of course once exported to another device (such as your laptop etc.) it only plays in slow motion. There are two settings for slow motion video, 1/8 and 1/4 speed, so I of course did 1/8.... that'll take 30 seconds of shooting and turn it into a 4 minutes of playback, with a really looong lead time if you start recording at the start of a 5 second count! I have to say I thought the results, however, were quite remarkable!

Naturally, I tried windows native video editor and ended up with results where the sound was literally out of sync with the video... but then I found an alternative called "clipchamp"... an Australian company bought out recently (afaict) by Micro$oft, so I hope they don't ruin it. Editing is quite easy with it although the interface isn't always the most intuitive (at least to me). I have not done much of this sort of thing so the criticism should be taken with a grain of salt. Clipchamp is free but there are of course pay-for upgrades (such as cloud storage etc.).

I've attached the video results of two flights... one, my Estes Sahara on an E18, the other is my Ventris on an F39. I'd love to know if anyone out there has any similar items (which I admit have not searched for yet!) The Sahara lift-off is very interesting to me (keep an eye on the exhaust early on!)
 

Attachments

  • Estes Sahara AT E18 slow motion - Made with Clipchamp.mp4
    18.4 MB
  • Estes Ventris AT F39 - Made with Clipchamp.mp4
    14.3 MB
Nice shooting, John. But you miss out on the best part of the launch; the LCO's announcement and countdown. :(
Too true!! While the video plays you can't even make out the voice. If I worked hard enough I could presumably edit it so the countdown would be at normal speed... Just for laffs, I did try to do an edit of the video at 8x the speed (since I shot at 1/8th speed) and the sound wasn't particularly pleasant... but that could be due to a lack of skill and or experience!!
 
Same idea, in mass production - I surveyed the NXRS launch site and scattered ten foot calibration poles around, then set a fixed 480fps camera to view (and measure) the launches. With a screen ruler (from SourceForge) and a spreadsheet, speed off the rail (when it was visible) and speed at/acceleration to 10 feet (to allow comparison across rockets small and large) were simple to calculate.

Speed off the rail ranged from 17mph to 110mph (Madcow Lil Goblin on an F22, 1.9kg scratch 38mm on a J570), acceleration from 0-10 feet from 1.88g to 58g.

The camera needed a full minute between takes to save data, so if the LCO oopsed or was too fast, I only had conventional video. Of 180 videos, I got 10 foot data off about 140. About a third of the high frame rate videos were off low power rods that could not be identified, so rail speeds for about 90 flights.

Videos are on a YouTube playlist at:

youtube dot com/playlist?list=PLVctyEBgbzIuEK7-qZgS-wRQqQ4D6piaW

The speed and acceleration are noted in the description of each flight I got useable data from. I don't know about anyone else, but I found the results interesting.

PS - I really like playback at 16x slow motion, at this speed, even a little pfft-pop rocket looks and sounds awesome.
 
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Same idea, in mass production - I surveyed the NXRS launch site and scattered ten foot calibration poles around, then set a fixed 480fps camera to view (and measure) the launches. With a screen ruler (from SourceForge) and a spreadsheet, speed off the rail (when it was visible) and speed at/acceleration to 10 feet (to allow comparison across rockets small and large) were simple to calculate.

Speed off the rail ranged from 17mph to 110mph (Madcow Lil Goblin on an F22, 1.9kg scratch 38mm on a J570), acceleration from 0-10 feet from 1.88g to 58g.

The camera needed a full minute between takes to save data, so if the LCO oopsed or was too fast, I only had conventional video. Of 180 videos, I got 10 foot data off about 140. About a third of the high frame rate videos were off low power rods that could not be identified, so rail speeds for about 90 flights.

Videos are on a YouTube playlist at:

youtube dot com/playlist?list=PLVctyEBgbzIuEK7-qZgS-wRQqQ4D6piaW

The speed and acceleration are noted in the description of each flight I got useable data from. I don't know about anyone else, but I found the results interesting.

PS - I really like playback at 16x slow motion, at this speed, even a little pfft-pop rocket looks and sounds awesome.
Nice analysis and videos!

PS. Nice scenery at your launch site!
 
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