A few people have shown interest in a discussion about ways to create slow motion. I will start this thread by explaining how I personally shoot slow motion with my XL2, then answering any questions people want to ask. Even if you have asked the question in another thread please ask it again here so we can start discussing it in one place. Thanx hope you guys enjoy.

Film in 60i. Pull that over to the computer as normal but be sure to use the scene detection option so that the clip is only 60i (kinda a duh but some people don’t know). Open After Effects and create a composition 2.5 times longer then the source file if u want ur final frame rate to be 23.976. If you want it to be 29.97 then set it 2 times longer. Then also set ur frame rate for the composition to whatever you want ur final frame rate to be (again kinda duh but I’m just going step by step).

http://i32.photobucket.com/albums/d18/thenextspielberg/Slow%20mo/1.jpg

Okay so now import your 60i footage. Right click on the footage in the project window and click on interpret footage. In the new window that has popped up under fields and pull down there is a place that says separate fields. If you are using HDV 60i then make sure it says upper field first. If you are using DV 60i make sure it says lower field first. Be sure to click “Preserve Edges”.

http://i32.photobucket.com/albums/d18/thenextspielberg/Slow%20mo/2.jpg

http://i32.photobucket.com/albums/d18/thenextspielberg/Slow%20mo/3.jpg

Basically what this has done for those of you that don’t know (there are some) is it has separated the fields and is treating the even fields as one frame and the odd fields as another frame. Preserve Edges tells it to interpolate the fields it isn’t using. But the clip is still to short so it isn’t showing all the frames it should.

Go up top to layer. Then click on time. Under time change the speed to 250% for 24p and 200% for 30p. If u have done everything correct you should be able to preview this and it will look like real slow motion. Export it and you are done.

http://i32.photobucket.com/albums/d18/thenextspielberg/Slow%20mo/5.jpg

http://i32.photobucket.com/albums/d18/thenextspielberg/Slow%20mo/4.jpg

This is how my man Robert Rodriguez did slow motion for Once Upon a Time in Mexico. The F950 were able to output 60p rather then 60i that the F900 did (if my memory serves me correct). Anyways hope this helps. Have fun.

(ADVANCE USER TIPS)
If u use HDV u can actually put that into a DV composition and not have to interpolate the lines u don’t have because each frame is 540 lines in a 480 line composition. But the color and gamma curve wont match the XL2 if that is what u are using to shoot ur progressive footage. I think also if u put a vertical directional bur of either 1 or 2 pixels it will smooth out the flicker.

Great info,
although I'm a PAL guy and have tried the 50i/seperate fields process but never got it to work...
you have any neat description on how to do the same with 50i`?
regards

I have never used PAL footage but theoretically the process should be exactly the same. Just change the numbers a bit. Make your comp 2 times longer, separate the fields the same way, time stretch, and export. If you can’t get it to work then put some 50i footage online so I can download it and play around with it. Make sure its not to long because I will need raw footage to make it work best.

Allan, thank you for the great info and starting the thread. Any thoughts on mixing 24pn footage with 60I (for the slow motion) and filters to perhaps match up the 60i footage to look close enough to the 24pn footage? I'm trying to avoid that total video look on my next project. It will be done for a Music video that will incorporate some slow motion shots.

Joe

I’m sorry but I don’t totally understand the question. If you film with a 1/120 shutter speed it will match up with 24p using a 1/48 shutter speed. The rule when shooting digital is use 2 times the shutter speed of the frame rate you are shooting at. If you shoot at 24 use a 1/48, if you shoot at 30 use a 1/60 and if you shoot at 60 use a 1/120. If every thing is the same with the camera (lens, gain, gamma curves, ext.) then it should all look the same. Can you be a little bit more specific about the “total video look” you are running into?

P.S. My name has only 1 L in it. (Alan)

I’m sorry but I don’t totally understand the question. If you film with a 1/120 shutter speed it will match up with 24p using a 1/48 shutter speed. The rule when shooting digital is use 2 times the shutter speed of the frame rate you are shooting at. If you shoot at 24 use a 1/48, if you shoot at 30 use a 1/60 and if you shoot at 60 use a 1/120. If every thing is the same with the camera (lens, gain, gamma curves, ext.) then it should all look the same. Can you be a little bit more specific about the “total video look” you are running into?

P.S. My name has only 1 L in it. (Alan)

I do humbly appologize for my mispelling your name.

What I was inferring to is, at least to my eye, when I record in 24p, it seems to just give the image a film like quality. I've had footage shot in 24p have some people question if I actually shot with film. To me, 60I just looks videoish. Great looking quality to say the least with the XL2. I still love how everything looks, no matter what frame rate I shoot with. Although I've only used 60I with the XL2 once since I've owned the camera. But I'll have to experiement with 60I. It could be I didn't have the shutter speed set correctly to 1/120.

No you are correct. 60i will always look like video. Not film. But 60p in a 24p sequence will look film like and be in slow motion. What I described above is how to get 60p out of 60i footage.

When talking about the “Film Look” some things you need to really discuss are shutter speed compared to the frame rate (which is 2 times more), Gamma curve (use the Cine curve), Depth of field (you cant really do much unless you get a mini 35 by P+S Technik), and dynamic range (this is how the camera reads light, this cant be changed without major modifications to the camera itself). 60i turned into 60p and rendered out at 24fps will look like slow motion film.

Do some quick tests of you doing fun slow motion stuff. The test I did was I jumped in the air and turned it into slow motion and it looked perfect. Aside from a few technical things that I couldn’t change (DOF, Dynamic Range) it looked just like slow motion film.

Hope this helps.

thanks alan, I'll try your recipe as soon as I get time to play with AE.

regards

No you are correct. 60i will always look like video. Not film. But 60p in a 24p sequence will look film like and be in slow motion. What I described above is how to get 60p out of 60i footage.

When talking about the “Film Look” some things you need to really discuss are shutter speed compared to the frame rate (which is 2 times more), Gamma curve (use the Cine curve), Depth of field (you cant really do much unless you get a mini 35 by P+S Technik), and dynamic range (this is how the camera reads light, this cant be changed without major modifications to the camera itself). 60i turned into 60p and rendered out at 24fps will look like slow motion film.

Do some quick tests of you doing fun slow motion stuff. The test I did was I jumped in the air and turned it into slow motion and it looked perfect. Aside from a few technical things that I couldn’t change (DOF, Dynamic Range) it looked just like slow motion film.

Hope this helps.

Yes, indeed thank you:) Can't wait to experiment as well.

I'm glad this thread was started. In a few weeks I will be shooting a motorcycle race and I intend to shoot part of it in slow motion. This scene will be a small part for my documentary. I'm shooting the film in 24p and was never too sure what was the best way to shoot good slow motion footage.

As an experiment while still in 24p I brought the shutter speed up to 180 and 210. Was this a good idea? I was wondering what this would do?

If shooting in 50i, why not just pull out the timeline in Premiere Pro to fit the time required for the slow-motion? Any comments? Why is it necessary to use After Effects?

Scott that was a good idea but its still harder to turn 24 full frames into slow motion then turning 60 half frames into 60 full frames.

Steve Premiere uses frame blending to create slow motion effects. It will just blend the interlacing and it will look HORRIBLE, at least compared to the method stated above. Try it out both ways and compare them at 100% magnification and you will see what I mean.

Thanks, Alan, I'll try it both ways..... Steve

If shooting in 50i, why not just pull out the timeline in Premiere Pro to fit the time required for the slow-motion? Any comments? Why is it necessary to use After Effects?

Haven't tried it in Premiere Pro, but Vegas handles slo-mo really well and gives great results very quickly.

Richard

Yeah Vegas is pretty good. It uses frame interpolation. Basically it will take two frames and figure out what comes in between them mathematically based off of how the pixels change. This is a very good way to make slow motion but its better to film in real slow motion then if you want it even slower slow it down with interpolation. The changes that happen between two frames of 24p footage is more then changes between two frames of 60p footage so the interpolation software will have an easier time accurately creating new frames for 60p then it will for 24p. Usually my rule is that I don’t making anything more then 2 times slower with interpolation. That is usually the point when quality drops because it has to create more then one new frame. So at 24p you only get 48 but at 60p you get 120 frames, way way more frames for not much more work.

Wondering if anyone can help with this....
1) Always used PPro slow motion without any problems.
2) Tried the AE approach, as detailed above....
Findings are as follows:
a) The overall frame brightness and contrast has changed from the original ( noticably slightly darker ) - hence when I import the clip back into PPro, it doesnt 'match' the surrounding clips - same background ( Church wedding )... more worrying is....
b) What I notice is a jitter on the Brides dress detail. I have monitored this in the source monitor and notice that adjacent frames are 'focussed' and 'blurred', hence creating the jitter at slo-mo speed playback.
c) Looking at the clips in the source monitor at 800% mag, I notice the same 'blockiness', hence I dont see how there can be an improvement in the slow motion effect???

I understand PPro uses blending, and AE uses some mathematical algorithm to interpolate the frames..... Just that I have the above probs and was wondering what I was doing wrong / failing to understand...... All comments welcome. Thanks.

Just checking the manual for PPRO.....

To blend frames for smooth motion
Motion in a clip may appear jerky when you change the speed of a clip, or output to a different frame rate. Make sure that frame blending is on to create new interpolated frames that smooth the motion.
Choose Clip > Video Options > Frame Blend.

Does this mean that PPro has interpolation, as the manual suggests it 'creates new interpolated frames' ?????

Your comments are appreciated.

Thanks

What Premiere calls “interpolation” is really frame blending, I have no idea why Adobe decided to call frame blending “interpolation” because clearly it isn’t. The jitter you are talking about it because of the line interpolation in After Effects. Make sure that you click the check box for “Preserve Edges” in the “interpret footage” menu. This should smooth out most of your problem, but if you are still having some apply a 1 of 2 pixel vertical directional blur. You will loose a slight bit of detail but it will look loads better.

I was just watching the “Children of Men” HD trailer and I noticed that at 1:39 mins into the trailer they used an interpolation software of some kind to create a slow motion effect. Check it out and be sure to look at their feet, and remember this is a professional trailer that probably cost thousands of dollars to make, and they were as limited as us when it came to creating slow motion. So the trade offs are having a “jelly” effect (seems to describe it well) caused by frame interpolation or lose a little bit of detail by interpolating scan lines.

[QUOTE=Alan James]Scott that was a good idea but its still harder to turn 24 full frames into slow motion then turning 60 half frames into 60 full frames.

Alan, I will definitely try it the way you have explained but I have a few more questions. First, I think my lack of editing and importing video plays a role in how fast I will understand all this. My editing software is FCP Pro HD. Before I ran into this thread, and this may sound a bit redundant, to make scenes in slow motion I would do the following: Shoot in 24p with the shutter boosted up a bit, import it into FCP and just slow the scene down 20-50%. My question is what are the pros and cons to this method and also do things change a bit because I am using FCP?

FCP uses frame interpolation just like Ppro. When comparing these two methods the only pros I can come up with is that there is no lose in detail in the frames that were actually recorded. The cons outweigh the cons of line interpolation however. Slowing down a clip 50% means two frames have to be blended in order to create a new frame. I have attached an example of an exploding brick wall I made then slowed down with frame blending. Frame 1 is a real frame. Frame 2 is made by blending frame 1 and 3 together, you will notice that there are 2 times as many bricks in it then the others and they are opaque. And Frame 3 is a real frame. Basically Frame 1 and 3 exist in frame 2 but are at 50% opacity.This is the drawback for using frame blending. If I were to have done this the 60i to 60p to 24p way it would have only slightly lost vertical detail, and with the XL2 when you shoot progressively its recommended you turn vertical detail to low anyways, so it would match up great.

One other thing. This works best in After Effects 7 becuase the line interpolation software is better. If you are using an older version on After Effects it wont work as well. One way to improve footage is to just put a larger vertical directional blur on it. This will reduce the flicker effect.

Does anyone have any video samples of the slow motion method Alan has described. I'm curious how it would look compared to some 16mm footage shot at 64 fps.

Well I can tell you with one hundred percent certainty that if the 16mm is exposed and developed correctly will look better. No doubt about it. I can’t comment on HOW much better it will look being that I don’t know if you are scanning it digitally then outputting from a digital source or making an optical print but it will be a noticeable difference. It will look better mostly because 16mm has higher “resolution” higher latitude and every frame originated from a progressive source. Again it depends on how the 16mm was shot, best shot 16mm at 64fps will look better then the XL2 shooting at 60i converted to 60p.

The celluloid vs. digital discussion is probably best left for another thread, but if anyone wants to further discuss how it pertains to slow motion I would request that we refer to 16mm and 35mm as “celluloid” not “film”. This is a point I have been trying to press amongst my friends and a habit I am trying to get into. A film is the final product not the material. Celluloid and digital (hard drive or tape) are both materials we used to make film. Thanx.

This might be a stupid question, but I don't have Adobe After Effects on my iMac, but I do have Motion 2. I can achieve a good smooth slow mo effect with Motion 2 like you guys are talking about with AE?

Thanks.

Does anyone have any video samples of the slow motion method Alan has described. I'm curious how it would look compared to some 16mm footage shot at 64 fps.

http://www.dvinfo.net/conf/showpost.php?p=607262&postcount=4

I've read somewhere that this technique (60i -> 24p) can be done solely with Final Cut Studio tools (specifically using Cinema Tools to conform 60i to 24p). Does anybody have any thoughts. I'd love to add that kind of thing to my arsenal. I love smooth slo-mo, and it's so bloody hard to do in the digital world.

I've read somewhere that this technique (60i -> 24p) can be done solely with Final Cut Studio tools (specifically using Cinema Tools to conform 60i to 24p). Does anybody have any thoughts. I'd love to add that kind of thing to my arsenal. I love smooth slo-mo, and it's so bloody hard to do in the digital world.


Yes, I am also curious about Steve's question.

Alan - maybe I need to start a new thread for this... but it relates here....

I film billfish, sailfish and marlin... what you're saying is if I'm shooting in 30p.. and I want a good slo mo shot... shoot 60i at 1/60? or 1/(the percentage slower)? Is that right? Also... using PPRO... is it bad to have a 24p project with a few 30p shots rendered into them? I guess... will it all look the same given that I follow the processes correctly, AND maintain quality?

pretty convoluted... sorry. LOL

oh... the other point... my older footage is in 30p, so I've been shooting in 30p with my XL2... if I use a shutter speed of 1/300 for billfish jumps, will that have the same effect as shooting in 60i? meaning capture more of the subject? or what benefit does shooting at a really high shutter speed have... it seems to make bites, and things that happen fast a bit clearer... is this correct?

Hey Alan,

I´m about to go out and test your 60i to 24p trick with my XL2. I´d like to add my "voice" to the growing crowd of people.

Thanks very much for the comprehensive tutorial... and I salute your stance on filmmaking.. ie:

"A film is the final product not the material. Celluloid and digital (hard drive or tape) are both materials we used to make film."

Bravo, sir!

"A film is the final product not the material. Celluloid and digital (hard drive or tape) are both materials we used to make film."
!

I thought that film was made from celluloid, comes in reels, and is the traditional medium used for making motion pictures or movies. But maybe I'm just being pedantic too? :)

Mr. Hunter? You´re a Major Player on DVinfo.net, DIGITAL VIDEO, and you´re gonna poo-poo the acceptance of digital video as a viable filmmaking medium?

Pedantic? Slightly.

Nothing is as peevish and pedantic as men's judgments of one another. — Desiderius Erasmus (1469-1536)

Hi Donovan. Sorry, you misunderstand my point. Film is used to make movies, so is video. To say that the end result *must* be called a film, to the point where people start *correcting* others' terminology, is what I disagree with. But I agree it's pedantic. :)

Richard

oh... the other point... my older footage is in 30p, so I've been shooting in 30p with my XL2... if I use a shutter speed of 1/300 for billfish jumps, will that have the same effect as shooting in 60i? meaning capture more of the subject? or what benefit does shooting at a really high shutter speed have... it seems to make bites, and things that happen fast a bit clearer... is this correct?
Higher shutter speeds reduce motion blur in the individual frame...so when you slow it down, you have a clearer image. No, 30p will not yield the same result as 60i, you need 60i so you can deinterlace each field set and give 60p which you can slow down to 30p and get a 50% slowdown...if you are delivering in 24p you can slow down another 10%. 30p doesn't help you at all.

Hey All. I've been away on a LONG spring break for a while. Nice to see that people are still chatting in this thread. I have a question about my own technique regarding color timing. If this technique is used what is the color timing of the final 60p sequence? I’d imagine that 2 frame back to back would each store half of the color information then 6 frames wouldn’t have any color information. My reason for asking is that I am going to be filming/recording/taping (whatever you wanna call it) a movie this summer all on green screen. Now I know DV isn’t the best for green screen but I imagine this process would make it worse. Can anyone help me out and suggest a method to make it better.

Also, there was a tutorial I once saw about creating an automated mask that follows a keyed area, so you only have to essentially deal with the spill and a little bit of green around the subject. Does anyone know what tutorial I’m talking about.

I’m sure this question is in the wrong place but… lol its three seemingly unrelated question that do actually relate, so idk where to ask.