OK. First question as a new user. I've been looking through the paperwork on my new 100HD and noticed that it will shoot in HDV 720 30fps Progressive which is great. It gives me a good look in playback but I need to do slow motion with my original footage. I need some of the footage I shot like 50% slower. In SD 60 its pretty simple, just cut the time in my NLE but it seems to me that slowing things down in the NLE and keeping it above 24 fps should work fine. But if I only have 30 fps to start with, slowing by 50% will result in messed up playback. So I guess my question is how do any of you who shoot 30p effect slow motion?
Slow Motion
- Thread starter filmgirl
- Start date
Not sure what you mean by 'messed up' but most NLEs will accomplish it one way or another--either by frame doubling or by frame blending to smooth it out. In the case of SD60 in Final Cut, some open the footage in Cinema Tools and conform to 30 fps or 24 fps before importing into Final Cut. Some take 30fps into a program like Shake which does an amazing job of interpolating pixels between frames. Not sure if that tells you anything you don't already know but those are some of the options.
jlames
Well-known member
I'm going to take our cameras out (and the day off) tomorrow and test various configurations. I just thought someone might have shot 30p @ 720 and then slo moed it in the NLE and could help. Anyone have experience in tis area? Sorry, hit the wrong button. Anyway, I'll let you know FG what our results are. We are going component out which means we get 720 @ 60p and slow motion in the NLE is easy but I've never tried the 30p. As I said, I'll try it tomorrow and let you know but there's alot of experience here in this area. Can anyone help?
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Elton
Veteran
30p conformed to 24p in, say, Cinema Tools will give you a 20% slow mo which is very slight. You will need to frame blend (smooth but gets fuzzy) in order to get a good 50% speed reduction.
If you have any way at all to record the analog 60p output of the camera head, you will get very nice results. With the XL-H1 I converted 1080 60i to 720 60p with Compressor, and then conformed to 720 24p with amazing results. It took a lot of rendering, but it was certainly worth it.
One thing I also recommend is shooting 60p with a faster shutter...say 1/100 to 1/250. I like the slightly steppy filmic slow mo this produces. At 1/60 shutter the slow motion can still look rather videoish, in my experience.
If you have any way at all to record the analog 60p output of the camera head, you will get very nice results. With the XL-H1 I converted 1080 60i to 720 60p with Compressor, and then conformed to 720 24p with amazing results. It took a lot of rendering, but it was certainly worth it.
One thing I also recommend is shooting 60p with a faster shutter...say 1/100 to 1/250. I like the slightly steppy filmic slow mo this produces. At 1/60 shutter the slow motion can still look rather videoish, in my experience.
Thanks jl and I guess it's Kool Aid Guy. I still need some help with this slow motion thing so any other recommendations are great. Hey jl, we were in Scottsdale yesterday (yes I finally got off the lot) and I ran into a guy who knows your guy, Mike Pellagatti. He say's he The Man when it comes to Discovery Channel and sports and nature lensing and coming from a DP on our show, that's a pretty good compliment. You DO have some good people working for you! And thanks brianluce. You'd be surprised at how many "chicks" are hanging out here without being seen. This is really a great area because you're a family here who sometimes argues but it stays at home. You all just help each other and that's why I'm here. So much good stuff to learn and maybe contribute. And a couple more chicks will be coming online in the near future when we make the big move to private production. We're banding together after almost 15 years in this business on the lot. Anyway, thanks. We like to think we add some class to the board! NO kidding, you guys are fun.
Gotta run but Please Help Me!!! on the slow motion.
Gotta run but Please Help Me!!! on the slow motion.
egproductions
Veteran
Correct me if anything i am about to say is inaccurate. All 720 resolutions are progressive so there is no way to get 60i unless you shoot in 1080i (does the hd100 do this?) If so maybe you should shoot the footage you need in slow motion at 1080i, apply the slow motion, downrez it and convert it to a 30p by a number of methods. If this is not an option i would think you should lower your shutter speed to 1/30 as opossed to 1/60 if you plan on slowing it down exactly 50% this should give you a smoother playback. When you take footage that was shot at 30P and slow it down 50% , as mentioned before, you arent playing it at 15 frames per second rather there are frames inbetween that are interpolated. at teh same token when you record at 60i and slow it down 50% its not the same as 30fps its more similar to 30i. Good luck.
There are many programs available which will use motion vectors to generate very accurate in-between frames. I've used Twixtor 4.5 to slow some 30P DVX footage I shot to 60P and the results were amazing. After Effects 7 Pro also has this "timewarp" functionality built-in. There's also Slowmotion and Motionperfect by Dynapel which can do a good job.
Elton
Veteran
The HD100 only shoots 720p at either 24 or 30fps to tape. It can play 1080i (cross-converted) out from the camera or the JVC deck. It also converts to 1080i in software like Compressor quite well. It's not quite like 1080i native (especially temporally) but can work.
If you want a good "overcrank" slow mo look, you need a full 60p recording to work with. And I don't recommend slow shutters for this effect. It will have too much motion blur between frames, and that's one of the tell-tale looks of "shot on video".
If you want a good "overcrank" slow mo look, you need a full 60p recording to work with. And I don't recommend slow shutters for this effect. It will have too much motion blur between frames, and that's one of the tell-tale looks of "shot on video".
jlames
Well-known member
FG- I told you, instead of starting your own house, just come over and play with us!!! OK just kidding. On of the things I love about you guys is that you're really committed to bringing a "new" production house into play and with your connections and talent, there's little chance that you won't succeed.
Anyway, thanks for th comment on Mike but he doesn't work for me but rather with me as he's a full partner in the company. His own Wildvisions in Phoenix is still going full throttle as well but he's a talented guy, no doubt; the calming effect to my driven nature.
As to your dilemma, the solutions mentioned above will get you by and are an excellent example of the depth of technical knowledge of the people here and how far you can go electronically to effect effects. But if you're doing what we talked about, there's simply no option for 720@60p out the camera's component connections.
The human visual system perceives motion through "persistence of vision" where the perceptual processes of the brain through the retina in the eye retains an image for a brief moment of time. But the eye is not a video camera so there isn't any "frame rate" or "scan rate" in the eye. Rather the eye / brain system has a combination of motion, detail and pattern detectors, the outputs of which are combined to create the visual experience.
The brain will perceive each of the "shots" in sequence and "expect" the next logical one in order. The rate at which this expectation exists is about 24 instances per second and the brain "fills in" the blank area in between. Slower than 24 fps and the brain says, "Hey, what happened to the next image?" and it stutters in expectation which we perceive not as you would expect, flicker but as confusion. The brain knows something is wrong but doesn't quite know what so it's not perceived so much as palpable flicker but an image distortion which is called visual acuity confusion. So the brain actually will put it all together down to about 16 fps but not well and at that point, confusion becomes actual flicker.
That's the Cliff Notes version but should be sufficient while I'm noshing lunch to see why there's simply no replacing native 60 fps footage for actual slow motion. A 50% reduction of 60 fps through the NLE causes the viewer, through persistence of vision, to perceive slowed motion at 30 fps; above the 24 threshold. But a 50% reduction in 30 fps causes the brain to perceive 15 fps, well past confusion and into the flicker range.
Anyway, thanks for th comment on Mike but he doesn't work for me but rather with me as he's a full partner in the company. His own Wildvisions in Phoenix is still going full throttle as well but he's a talented guy, no doubt; the calming effect to my driven nature.
As to your dilemma, the solutions mentioned above will get you by and are an excellent example of the depth of technical knowledge of the people here and how far you can go electronically to effect effects. But if you're doing what we talked about, there's simply no option for 720@60p out the camera's component connections.
The human visual system perceives motion through "persistence of vision" where the perceptual processes of the brain through the retina in the eye retains an image for a brief moment of time. But the eye is not a video camera so there isn't any "frame rate" or "scan rate" in the eye. Rather the eye / brain system has a combination of motion, detail and pattern detectors, the outputs of which are combined to create the visual experience.
The brain will perceive each of the "shots" in sequence and "expect" the next logical one in order. The rate at which this expectation exists is about 24 instances per second and the brain "fills in" the blank area in between. Slower than 24 fps and the brain says, "Hey, what happened to the next image?" and it stutters in expectation which we perceive not as you would expect, flicker but as confusion. The brain knows something is wrong but doesn't quite know what so it's not perceived so much as palpable flicker but an image distortion which is called visual acuity confusion. So the brain actually will put it all together down to about 16 fps but not well and at that point, confusion becomes actual flicker.
That's the Cliff Notes version but should be sufficient while I'm noshing lunch to see why there's simply no replacing native 60 fps footage for actual slow motion. A 50% reduction of 60 fps through the NLE causes the viewer, through persistence of vision, to perceive slowed motion at 30 fps; above the 24 threshold. But a 50% reduction in 30 fps causes the brain to perceive 15 fps, well past confusion and into the flicker range.
Elton
Veteran
Filmgirl,
Here's an example of H1 1080i converted to 720 60p in post, then conformed to 720 24p for the slow motion look. It's some basketball footage from Laguna Beach.It was shot with a 1/250 shutter to enhance the clarity of the slow motion.
www.homepage.mac.com/mrbarlowelton
it's a 720p HD quicktime file. You'll need the QT7 on Mac or PC to view it.
This is why I say you should try to get the 60p if you want the best effect.
Here's an example of H1 1080i converted to 720 60p in post, then conformed to 720 24p for the slow motion look. It's some basketball footage from Laguna Beach.It was shot with a 1/250 shutter to enhance the clarity of the slow motion.
www.homepage.mac.com/mrbarlowelton
it's a 720p HD quicktime file. You'll need the QT7 on Mac or PC to view it.
This is why I say you should try to get the 60p if you want the best effect.
jlames
Well-known member
I've just seen some Twixtor results run through After Effects and I have to tell you, I'm not a cinema guy and this is definitely not a cinema shop, we do television, but the results are absolutely incredible. JVC 100HD set to 720 / 30p on a vehicle travelling approximately 35 mph slowed 50% and played back on a JVC HD 42" plasma, not LCD, monitor and it really looked great. We'll still be going 60p but IMHO, if you're restricted to the camera's 30p in HD and need slow motion, this product is really functional.
http://www.revisionfx.com/rstwixtor.htm
Neophase is exactly right on his After Effects 7.0's inherent capabilities but the guys here are familiar with Twixtor and really recommend it. Not too bad of a learning curve, plug-in direct to AE and seamless integration from what I hear. From what I see, again, great results.
http://www.revisionfx.com/rstwixtor.htm
Neophase is exactly right on his After Effects 7.0's inherent capabilities but the guys here are familiar with Twixtor and really recommend it. Not too bad of a learning curve, plug-in direct to AE and seamless integration from what I hear. From what I see, again, great results.
hatsoff2halford
Well-known member
If you are using the BR-HD50 deck can't you record 720p60?
-Logan
-Logan