"Jumping a Car" Effect

Hello Everyone,

I am working on a Hitfilm tutorial based on an old Film Riot tutorial on how to jump over a car. The original Film Riot tutorial is now seven years old (published on August 20, 2009) and was done in After Effects. I have created a seven second sample video, and I would like any and all feedback I can get on it before I make the tutorial. I appreciate everyone's opinions on the forums, and I have learned a lot from all of you! Thanks in advance for taking a few minutes of you time to check it out.

https://youtu.be/xkZatbbWgF8

Here is the SECOND VIDEO...

https://youtu.be/40BUn3ofd3o

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Comments

  • nice work. a little bit too low gravity for the jump... the jump and the landing is to linearly

  • It looks like you filmed the jump and car  with a  higher than normal shutter speed.  So, for me, it would benefit from some added motion blur. 

  • @chriguf That is what I thought too. I think I may have to change the speed of the jump to reflect a higher one than I actually did.

    @BobDiMarzio I actually filmed it with my cell phone. I will play around with motion blur to make it feel a bit more real.

    Thanks to both of you for the feedback!

    I look forward to more comments.

  • I like it, well done!

    I don't think you're going to be able to remove the shadows that popping in and out though. The cut in the beginning is noticeable, but not as noticeable as the shadows.

    Kevin

  • @CitrusNinjaKick I learned a lot from going through this exercise. One of the things I learned is that I need to more carefully pick the location to film.

    The original clip is over two minutes long because I first ran out into the street, did the jump, then I ran over to my car and drove it down the street, turned around and came back driving by the camera. Given that it was a particularly windy day, the clouds in the background moved considerably. Also, the lighting changed between my jump and my driving the car by, so that made the masking more obvious. I had to do a full sky replacement, and I did my best to color correct and adjust the brightness levels of the clips. This is obviously not something that I am very good at. If I were to do it again, I would pick better location where the sky isn't visible in the background, I would film at a time when I was sure the lighting would not change, and if possible, I would get someone to drive the car by as soon as I completed to jump, minimizing the lighting changes.

    Having said all that, I agree with you that the shadows popping in and out are not going to get any better in this video. Thanks for the feedback! :)

  • The lighting changes are very noticeable. Can you mask around the car as much as possible and blend with a large feather into some part of the background shot to even it out over the entire shot?

    Also, can you zoom in, even if it means making a 1080p project into a 720p one? You're so tiny in the shot it doesn't look dangerous at all.

    Watch this other tutorial by SurfacedStudio. How to Get Hit by a Car

  • @Palacono Thanks for the feedback!  I think I may start again and mask the car with it's shadow all by itself.  The video you linked me to is great! I will still have to mask myself, but I have already done that, so I should be able to use that work footage again.  I think that may be the answer to the shadows problem.  Thanks again... that is great advice!

  • @Senseihaynes

    Film it again except this time frame it closer as @palocono said and first film you driving the car. As soon as you clear the camera, jump out and perform your jump.  This could minimize lighting/shadow  changes since the car and jump sequences should only be seconds apart.

  • Stargazer54Stargazer54 Moderator
    edited September 2016

    @Senseihaynes All things considered, that is

    a great test shot!

  • @BobDiMarzio - Makes sense to me!

    @TriFlixFilms - Also good advice!

    @Stargazer54 - Thank you!

  • Okay everyone,

    I have spent a little time creating a SECOND VIDEO using some of the ideas offered up on this thread. Please watch it and provide me some more feedback. I believe I have fixed the shadows popping in and out.

    I appreciate everyone's comments. I have already learned a ton by going through his exercise and from your comments. Thanks everyone!

    https://youtu.be/40BUn3ofd3o

  • That looks nicer than your previous attempts!

    I'll concentrate on the speed of the jump because that's what struck me: your take-off feels unnatural, too sudden. And I discovered that your position is exactly the same on frame 4;20 and on the next one. You're frozen, and this creates a "stop and instantly accelerate" motion.

    The rest of the jump looks good enough to me. As a matter of fact, I measured the "altitude" of your center of gravity on my screen, frame by frame. You're supposed to accelerate while you push with your legs, and descelerate when your feet leave the ground and until you land. Yeah, I like pshysics (as long as they remain simple ;) ).

    So, to polish your jump, my advice would be:

    1/ move down just a bit (2 or 3 pixels) your jumping character on frame 4;20 and move it up by the same amount on frame 4;21. That's the most important fix.

    2/ Your altitude remains exactly the same on frames 4;28, 4;29 and 5;00. Well, you should be higher by 1 or 2 pixels on frame 4;29, but I'm being very precise here and it doesn't matter that much.

    The rest of the jump (I measured on 22 frames) is rather good and the curve I got with the figures I measured has that nice parabolic shape it should have. In other words: it looks realistic.

  • edited September 2016

    Looks much better on the lighting, no visible pops at all.

    What Cervier said about the jump, plus....zoom in.

    Even though it's only 720p, no one will notice if you're subtle and add some Unsharpen Mask Effect to it afterwards to bring back some of the lost sharpness/detail.

    Even better add some fake camera shake so it looks handheld and less like a tripod shot set up to do a VFX test.

    Kirstie showed you how to do that on the Hitfilm channel some months back.

  • It looks much better indeed. Except the above comment i think there is a small jerkiness right above in the sky of you after you jump. That is easy to fix i think and falls more in the nitpicking category :)

  • [EDIT] About what I wrote at "1/". It's by 5 pixels(*) you should move down (resp. move up) your character on frames 4;20 and , erratum, not 4;21 but 4;22. I read my notes too fast, sorry...

    (*) If your video is indeed in 720p

  • edited September 2016

    As I wrote above, what you did looks good enough for me. But I noticed your project was, in a way, a bit more difficult than what's in the tutorial from Film Riot: they didn't make is look as if Josh jumped higher, whereas you increased the height you really jumped to.

    It make me think about what it implies. The main thing is, if you throw in the air something that's not self-propelled (yourself when you jump for instance), the duration of its "flight" depends on how high it goes. The higher it goes, the longer the travel.

    And that explains why some jumps or throws can look jerky or articifial: if you extend the travel, but not the duration, it looks un-naturally fast.

    Simply put, if you throw something K-times higher, it will stay in the air square-root-of-K longer. Throw something twice as high, its travel will last 1.4 times as long.

    But I've learned over the year it's not because something look exactly like reality that it is believable. Hollywood has accustomed us to people being thrown back by a 10 gram bullet as if they had been hit by a 2,000 Kg car for example.

    So I did a quick and dirty (dirty masking...) test:

    ** Short video here **

    - First part: I throw an object up

    - Second part: I make it look as if it was going twice as high. Doesn't look real.

    - Third part: I cut just after the object left my hand and just before I caught it back, and expanded that part of the clip by 40% (in other words, I multiplied its length by 1.4) -- it feels nicer.

    Except, of course, that the job I did at masking is ugly and that the fact I didn't move my face to look at the "new" trajectory doesn't sell the effect. I know. This is just a quick test to go with this post (the video is not "public") but I think it does the job of getting my point accross. Hopefully ;-)

     

  •  @Cervier

    I had done a similar test in the past to simulate the trajectory of a 55gal drum being blown into the air.  I went outside and using a Gopro on a tripod set @ 120 fps, I videoed myself  throwing a soccer ball about 25-30 feet into the air.  I noticed that there are 4 stages.  (1) Acceleration (2) Deceleration to zero  (3) hang time  (not really stationary but the time it takes for the ball to stop it trajectory up , followed by reversing it's path down with an acceleration going down.    I brought the footage in to Hitfilm Following the balls path and speed and set a  key frames approximately every 10 frames to match the ball's path.., (I really do not remember that exact amount of frames between the key frames but 10 seems to stick in my mind)        I parented a 3D CGI  barrel to the points against a clean plate and the results looked convincing.     

  • edited September 2016

    Thanks to everyone for your feedback. After reading the comments and watching the video that @Cervier posted, I went back and  slowed the entire jump down using the Rate Stretch tool. Right away, I notice that while the timing seems more correct, the explosiveness of the jump is also slowed down, which contradicts the idea that I would go higher by jumping slower. I think perhaps ramping the speed of the jump at the beginning, then slowing down after may be the way to make it look more real. However, that sounds good in theory, but may actually be somewhat tricky in practice!

    I have not added any camera shake or other effects because I am mostly focused on the jumping at the moment. I do think that is a good idea, and I am grateful to @Palacino for suggesting it. I will add it later.

    Lastly, Cervier mentioned that there is a frame that is duplicated just before the jump. I went back and found it. For some reason the footage out of the cell phone made two frames identical, which I found very strange. The good news is... it wasn't my fault. :) It was a simple matter of removing the duplicate frame to fix it. Good eye catching that, Cervier!

    Here is Video Number 3 with the slowed down jump footage...

    https://youtu.be/yvqnJ06DTYA

  • @senseihaynes ; That's looking pretty good!

  • Looks a lot better, but the motion blur on yourself isn't matching the scene (not high enough). I think if your upped the blur a little more it would really sell the effect.

  • @senseihaynes Did you do anything to your cell phone footage before using it in HitFilm by any chance?

  • @Stargazer54 - Thanks! It has definitely improved due to the feedback from the group.

    @TriFlixFilms - I agree. I will play with the motion blur settings some more.

    @Aladdin4d - I ran it through Handbrake.  My phone is an LG G3, and it has been outstanding when it comes to filming stuff. It definitely records in a VFR, but Handbrake fixes it perfectly every time!

    @Kadri - I didn't notice the jerkiness above the jump point until you pointed it out. Also, it seems that there is a change of focus as well. I have no idea what is causing that. I may have to take another look at the original footage that makes that part of the scene. Thanks for the feedback!

  • @senseihaynes Handbrake is the culprit then. It usually does a very good job of converting VFR to CFR but it will occasionally duplicate frames to make up a difference. That's not unusual most tools that can do VFR to CFR conversions will do the same thing. The only way to fully avoid it with VFR footage is to use frame interpolation and that's a whole other ball game.

     

  • @Aladdin4d - That is very good to know. I will definitely pay closer attention to that in the future. Thanks!

    @Kadri - After looking carefully at the footage, the problem seems to be two fold. 1... The Youtube compression algorithm has created some artifacts that are not in Hitfilm's final file that I then uploaded. 2... When I did the Rate Stretch on the clip of the jump, the Mask that I had applied "smeared" (for lack of a better word) across more frames that were created by the stretch of duration. This (partly - along with youtube) caused the "jerkiness" above my head in the jump. The first one I can't do anything about, but the second one is an easy fix!

  • @senseihaynes ; Youtube problems do come quite along lately.

    I think there are kind of very small light flashes too above the part and around you. It is probably the same reason as you posted above?

  • Wow! That looked REAL! I did think slowing down the jump was the way to go, but I only that one short test. In your video, I felt the result was spectacular! I'm impressed at how well it worked, good job!

    Regarding the "explosiveness" of the jump, if I'm not mistaken, you slowed it down starting BEFORE you leave the ground. The steched out part begins when you throw your arms back to _prepare_ to jump. Well, you want to keep the speed of that pushing motion as it is.

    So, cut at the point your feet don't touch the ground anymore (cut between frame 4;22 and frame 4;23) and between the last frame when you're in the air and the frame you touch land.

    This will keep both your take-off and landing at the right speed. But if you want to speed up something, let that be the pushing motion, when your feet are on the ground. It does make sense you'd have to push harder (faster) to jump higher.

    One last comment, about other effects, taking a closer shot and so on. IMHO, those are artistic choices. If you intend to make a how-to tutorial, I agree with you that you should focus on the technical aspects and leave aside what depends on taste

  • Whoa @senseihaynes I'm super impressed. Going through this whole thread, from your very first car jump video to the latest one, I'm blown away by the difference and how much you've learned from just this one exercise!
    The latest one could absolutely be real - gravity, timing and shadow is spot on! Look forward to seeing what you can do with a new clip :D

  • Much, much better, but I see one micro section that I'm not entirely sure about, but my brain says "Eh?"

    I think it is just after you take off and somehow it looks like your body slows down while you pull your legs up. It was more noticeable the first time, then on every other time I watched it I got used to it and found it hard to spot, so I'm actually trying to remember where it was. 

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