Slow motion (120fps) using KU990 mobile phone?

Folks,

I wondered how to film a modelgun action to show more details than usual. Resolution is one thing, but being able to do slow-motion would be cool. Unfortunately such cameras cost an arm and a leg. The cheapest (at over 1000GBP) is probably Sony SR12, it can record about 3 seconds at 240fps, played at normal speed this gives 12s clips.

Surprisingly there is a mobile phone (LG KU990i) that can record at 120fps of unlimited length! It is replayed at 15fps, giving 8x slowdown. Downside is resolution: only 320x240, like a webcam, or many Youtube videos. Phone is much, much cheaper, about 150GBP. Many sample movies are on Youtube, just search for "ku990 120fps".
Compilation of a few clips (why people like to film a lighter or a match so much?):
https://www.youtube.com/watch?v=buePr5S7b_4
A lightning:
https://www.youtube.com/watch?v=fed9x_n8B70

If you have or can get access to such phone, please try recording a firing modelgun so we can see if it is any useful :-)

Hint: when filming slowmotion, use PLENTY of light on modelgun. Due to speedup camera needs much more light to be able to get a decent quality. "Image is too dark" is usual complaint for quality from people unaware that so much light is needed.

But the background has to be black in order to show the weaker muzzle flash more...maybe because the 0.01g of gunpowder burnt a lot quicker than live/blank ammo...

Slow motion filming can be a really good way of seeing why feed or jamming problems happen. Forum member Fledermaus posted a selection some time ago:-

https://mp40modelguns.forumotion.net/modelgun-videos-f2/marushin-mp40-video-slo-mo-and-tutorial-t1377.htm

Some time ago my son paid me a visit and filmed my MGC MP40 firing with a mobile phone he reckoned was at 12fps. Unfortunately he forgot all about sending me a copy after he returned home. The footage was slow enough to see every stage of Automatic firing slowly enough to follow easily. Shell ejection was very impressive.
The only problem was lack of light, even though the room was well lit, additional lights would definately be needed to give really good images.

Youtube has several examples of Airsoft GBB guns and some PFC models filmed in slow motion. The best ones are usually filmed with the Sony camera

Thanks for the link Cerwyn - description for YT video says it was done with Casio EX-F1 camera (still/video). From description it can do 1200fps! 40x slowdown! It seems impressive.

Muzzle flash taken with video camera at 25fps (normal speed) seems to be seen only on one-two frames, but blowback and cartridge eject take a bit longer. This is promising - action should be slow enough to get at least a few (8-10) frames with slow-motion, giving 0.5 to 1s playback, enough to see what is happening.

Agree with jim, background should be selected carefully, experimenting to see what works best.
For still shots there should not be much contrast between object and background, otherwise you can't see details of a (usually black) modelgun. Black background means unfortunately that camera tries to have a longer time to compensate for low light -> scene needs even more light. That's few factors to take care of, but a bit of practice should clarify that :-)

I thought that was very impressive my mobile video footage looks like it's been shot on very poor CCTV from 5 miles away in the dark

I have just purchased an old KU990 and will post a few vids when i get it

That's a spirit! :-D

I think I'll get one too, prices on second-hand ones are not that bad.

It arrived today it cost £35 from ebay so not to bad

Here are my first vids of a problematic Wa Shan SIG 220



Click here to View https://s74.photobucket.com/albums/i273/88ace/MG/?action=view&current=sm1.mp4



Click here to View https://s74.photobucket.com/albums/i273/88ace/MG/?action=view&current=sm2.mp4

That slow mo really helps!
Was there a mag fitted in the second vid? as it looks as though the cart clips the top of the mag/next cart on the way back??? causing premature release from extractor before hitting ejector??
Does it eject ok with one round chambered and no mag fitted??
Got to get me a KU990!!

I was quite pleased it's not fantastic quality, it struggles with close up video and needs a lot of light (second clip) but with a tripod it should show some detail.

The mag was in both times (just one round) so I’ll have to look to see if the slide is coming back far enough or the extractor is letting go to early (which it looks like doing)

8ace

Good price!

Quality is definitely not the same slow-motion we see on science or nature shows, but there seems to be enough information for troubleshooting. To be honest modelgun action is faster than I expected, but your P220 videos show cartridge behaviour pretty well.

Your comment about light is very valid - when filming 4x faster, camera needs 4x more light to get the same level of exposure. This is often overlooked and results in low quality.

not done with a moby but in the slow mo topic. ( mods split topic if you wish )

shot at 300fps



Also shot at 300FPS
the third round here flicks upwards and gets wedged between the bolt head and charging handle ..this is due to wear on the ejector plate on the ABS MGC model ( a bit of weld filled flat will sort this )
what is interesting here is the amount of shock movement in the barrel area …this area is solid with no wobble and I am quite surprised to see the violent movement upon firing



As Ace says sufficient light is a major problem and I`ll have to build a light rig or buy some photographic umbrellas

DOC

That's quite a wobble!

Thanks for posting these, I think the videos are useful in this thread.
300fps would be a Sony SR, Sanyo Xacti or Samsung SC-HMX video camera, right?

Casio EX-F1 and it will do 1200FPS but I really dont have enough light yet to do that speed justice and firing any sort of gun outdoors these days isnt a great idea

DOC

there`s 600FPS ..the action happens at .22




Nakata MP40 at 300FPS



its hard working firing one of these one handed at reaching to press the shutter

this was a bit close ( although I have a lens shield fitted )



next spare weekend job is build a lighting rig !

DOC

Edit : the quality of these is being reduced/compressed by photobucket by the way

These look brilliant! The sparks in the first video are fantastic :-D

At such slow speed all details can be seen clearly. I hope you succeed with lighting the scene to get even faster :-)

Got a few more as i got a cheap 500w light to help out

Here's a few shots of modelgun and airsoft slow-motion (300/600/1200 frames per second = 1/10, 1/20 and 1/40 real speed):
https://www.youtube.com/watch?v=1wwQLEfapCQ

I could watch those slow mo films all day