pre-meditive slow-motion

Post by **anitasanger** » Sat Nov 18, 2006 8:11 am

okay, i'm seeing a lot of slow-mo clips on here that are blowing me out of the water. namely this guys http://www.steve-hyde.com bird work. anyway, i'm trying to grasp the concept of this slow motion film stuff. i'm assuming that none of this is done in post production, right? how is this done? i thought that i read somewhere that if i shoot speeds on my beaulieu at lets say 70fps, it will play back in slow motion. if this right, how is it so? why would more frame's make things slow? the learning curve from video to film is one i wish i never would have to make. i wish i were born in the 50's.

thanks.

Post by **Patrick** » Sat Nov 18, 2006 9:11 am

Why does running the camera at a faster than normal speed create slow motion? The answer to this is very simple. As you know, the standard filming speed of super 8 can be 18 or 24fps (to simplify matters, let's just call it 24fps.) In that case, the standard speed of projection will also be 24fps. So if you film motion at 24fps and then later project this footage at the same speed (24fps) motion will appear normal.

However, let's try something a little unusual. Let's film motion at a faster speed - say at 32fps and then project this same footage at the standard speed of 24fps. The motion will appear slowed down because it is being projected at a slower speed. In this case, the projector speed is slower than the camera filming speed - so motion will look slower. The camera was transporting the film at 32 fps - but the projector was transporting this film at the slower speed of 24fps.

Now let's try something similar but a little different. Let's film motion at 54fps which is a considerably fast speed. Once this film is developed, we'll also project this latest footage at normal projection speed - 24fps. In the previous example, 32fps was only slightly faster than 24fps. In other words, 24fps was only slightly slower than 32fps - therefore motion was only slowed down very slightly on projection. However, 24fps is much slower than 54fps so motion will be slowed down considerably - you will get more exaggerated slow motion filming at 54fps. So basically, the faster you run film through the camera, the slower the motion will appear when that footage if projected. This is why slow motion filming is often called 'high speed cinematography.'

There are some high speed cameras available in 16mm and 35mm formats that can run at speeds over 100 fps such as 400fps. These would be ideal for filming hummingbirds in flight etc. There are even high speed cameras that can run over 1000fps for super slow motion.

The 70fps on your Beaulieu is quite impressive. Very few super 8 cameras run that fast. Though unfortunately, I have heard that due to the limitations imposed by the super 8 cartridge, such high speeds may not be all that steady. Someone once posted that with the special accessory pressure plate, he/she was able to get quite steady footage from his/her Beaulieu at high speeds. But do a test anyway to see how steady your footage is at 70fps before worrying about the need to purchase this expensive pressure plate or not. By the way, never run a movie camera at speeds higher than 24fps when there is no film inside...it is possible to damage the intermittent movement of the camera supposedly.

Oh and lastly, fast motion like time lapse is achieved in a similar way to slow motion filming. When film is run through the camera at a very slow speed, like 9fps or 1 frame every second, motion will appear faster upon projection because in this case, the projection speed (24fps) is faster than the filming speed.

Post by **anitasanger** » Sat Nov 18, 2006 9:19 am

wow, thank you for the informative explanation, i love those! i thoroughly understand now. thank you much! what is the best way to shoot time-lapse footage on a beaulieu zm4008? lets say ten minutes worth of clouds moving across the sky, set to move really fast and dramatic? filmed at 24fps and projecting at 24fps. and since your so informative, i'm going to ask you a few more questions.

1. what is the use for the frame counter on the beaulieu, the big round dial?

2. how does one accurately set their beaulieu to film at 24fps? mine just has numbers for 18 and 24 i think.

3. when the film is sent to a transfer house, how do they know what speed the film was shot at? do you have to tell them, or do they know somehow? so if i filmed it at 18fps and they transfered it at 24fps, wouldnt everything look too fast? and since the beaulieu doesnt have exact notches for certain fps settings, how can the transfer be set up to be exact?

thanks again.

Post by **Nigel** » Sat Nov 18, 2006 9:30 am

Wow...

I wanted to say something else but I would have just sounded like an Ass.

Good Luck

Post by **Patrick** » Sat Nov 18, 2006 9:59 am

Umm.....filming clouds at 24fps and projecting the footage at 24fps would make them look normal. But I guess that's not the effect you wanted! When Ive done time lapse of clouds, Ive found a wide variety of interval times to be suitable...it all depends on the speed of the clouds. For very slow moving clouds, 15 second intervals might to the trick. If the clouds are moving quite fast, 4 second intervals would be more suitable. Adjust interval times as needed for cloud movements inbetween 'fast' and 'slow'. Remember though that this is not an exact science. These intervals are just rough approximations that have worked for me. You'll need to experiment.

As for the other questions...

1. Ive never used a Beaulieu but i assume the frame counter simply counts individual frames that are exposed.

2. I would just line up the dial as close to the '24' marking as possible - ie right along side it.

3. I'll let the people experienced at telecine answer that one.

YouTube · Post by **Andreas Wideroe** » Sat Nov 18, 2006 1:46 pm

anitasanger wrote:3. when the film is sent to a transfer house, how do they know what speed the film was shot at? do you have to tell them, or do they know somehow? so if i filmed it at 18fps and they transfered it at 24fps, wouldnt everything look too fast? and since the beaulieu doesnt have exact notches for certain fps settings, how can the transfer be set up to be exact?

You need to tell the transfer house what framerate you've shot your footage at. Otherwise they'll try to determine speed, but that's difficult unless you see people in the image.

All professional transfer houses have orderforms where you need to enter details about your production.

Otherwise they'll probably just scan at 24fps or 25fps in Europe or 29.97fps for the US.

The Beaulieu has probably just as accurate fps as any other NON crystal sync camera.

Regards,
Andreas

Post by **Rollef** » Sun Nov 19, 2006 4:14 pm

anitasanger, do you have a projector? just film some and project it when you get it back. Try 9, 18, 24 and 54 fps of some thing moving and then project it all at 18 when you get it back.

Here is some history for you:

18 fps have "always" been standard for non sound super 8
24 fps for sound super 8.

Some cameras can film faster and slower, some can't.

Imagine you took one picture every day of someone building a house until the house was finished. That would be a really slow fps, and if you projected that at 18 fps or 24 fps (either way is fine in this case) you would se the house finish in front of you.

Set your 4008 to the slowest fps it's got and try to film some clouds. Use a tripod. In this way you'll get fast moving clouds when you project your film.

Post by **anitasanger** » Tue Nov 21, 2006 12:22 am

thank youv ery much guys. great help as always!

Post by **anitasanger** » Wed Nov 22, 2006 11:22 pm

rollef, yes that does seem like it would be the best way. slow filmed speed projected at a normal rate. i don't have a projector yet, but am looking. although, i do have an old one i inherited from my great grandpa, but i think he used it for regular 8, will this still work with my super8? just thinking about it, it seems like filming stuff to look in fast motion could get pricy huh? i mean 3.5 minutes worth of clouds moving filmed at 4fps projected at 18fps wouldn't look like much, would it?

Post by **audadvnc** » Wed Nov 22, 2006 11:30 pm

anitasanger wrote:i do have an old one i inherited from my great grandpa, but i think he used it for regular 8, will this still work with my super8?

Nope, it'll wreck your film on the first pass. Don't even try it.

Post by **bakanosaru** » Wed Nov 22, 2006 11:41 pm

just thinking about it, it seems like filming stuff to look in fast motion could get pricy huh? i mean 3.5 minutes worth of clouds moving filmed at 4fps projected at 18fps wouldn't look like much, would it?

It sounds like you've got it backwards. Filming fast or slow motion isn't going to cost you anything more or less. After processing you'll still have 3.5minutes at 18fps or 2.5 at 24fps.

Where things can get pricey is filming slow motion and not getting the shot first time. At 70fps for 10seconds of screen time (at 24fps) you'll only need about 4seconds of shooting so you need to pick that 4seconds carefully. On the other hand at 4fps 10seconds of screen time (at 24fps) will take 60seconds of shooting.

Personally I don't think 4fps is slow enough for anything but very fast moving clouds. For clouds I would go for 1 frame every 5 or 10 seconds which on the 4008 you'll have to do with a cable release.

Post by **anitasanger** » Wed Nov 22, 2006 11:47 pm

okay, i was thinking with digital video, i would just put it on the tripod and push record. then in the end, i would speed it up ridiculously fast in post for the fast foward effect.

Post by **johnnhud** » Thu Nov 23, 2006 3:28 am

You may find this to be interesting then. I did a time lapse on my digital camera just the other night. I shot the Dallas skyline as it faded from dusk to night. It was really pretty cool. Here are two clips.

The first is the whole shoot, sped up by 15000% with frame blending enabled.

http://web.mac.com/johnnhud/iWeb/Site/C ... 08BF0.html

The second is more stylized, I like it better. While it's not scientificly accurate, I think that viewers would expect to see it more than they would the other. Plus I just think it's cool!

http://web.mac.com/johnnhud/iWeb/Site/C ... 75068.html

Post by **anitasanger** » Thu Nov 23, 2006 4:05 am

neat man, i liked the second one best. how many rolls of film would it take to do a sequence like your video? dusk to night?

Post by **johnnhud** » Thu Nov 23, 2006 5:36 am

Well, you wouldn't want to shoot it on film like I did on DV. If you did, you would burn through something like 24 rolls of S8mm film. You could shoot the whole thing on 1 reel though. Just set the camera (assuming your camera has this capability) to take 1 picture every so many seconds, (1 pic a second compresses 24 seconds down into 1 second, when projected at 24fps, one pic every 2 seconds will compress 58 seconds into 1 second)

Let the camera click away for an hour or so then develope the film. Play it back at 24fps and Viola, the timelapse is complete. The only "bad" thing about this method is that you can't really slow down the timelapse if it's to fast. Also, you can't really adjust a lot on the finished product, so that simply means you will have to be more skilled to do it.

Try it with the DV cam first, you'll save some $$