I edit a lot of film using slow-motion.
When I slow it right down to say 30% however the
movement is not quite so fluid however, and can actually
be a bit juddery looking at times. I can appreciate that it might
be because of the frame rate (24fps) and the fact that
it is being reduced when being played back, but how then
is it that I've seen a lot of adverts and even on films whereby
the movement is seriously slow, yet there is no judder in the
movement? Is it because they're using better cameras?
I use a Canon XM2 and edit with a dv500dvd card and premiere
6.5. I also commit to DVD with Adobe encore.
I also use xm2 - page 75 of manual shows shutter speeds that are available, but this will no doubt still be recorded to tape as 25fps (PAL).
This will ensure sharp pictures, but won't stop judder.
To clean up 'phone footage' at 18 fps I have tried, stacking the same track '2 up' with one tack say 1 frame ahead (depending on % slowed) and top track 50 percent opacity.
In my case it meant a less sharp image, but less juddery.
AFIK Film cameras(as distinct from video) (and scientific equipmnet) can film things at say 100 fps, so when slowed to 25%, a frame rate of 25fps is maintained - which is the threshold of the human eye, below which, flicker is seen.
Dave.
"To clean up 'phone footage' at 18 fps I have tried, stacking the same track '2 up' with one tack say 1 frame ahead (depending on % slowed) and top track 50 percent opacity."
Dave, not sure if I understand you properly.
Do you mean simply duplicating the track
puting it into another track, moving it one frame up,
and then reducing the opacity of the first clip to 50%?
Yes -exactly.
Depending how much you slow, the intention is to keep a 'layer below' to try and make the frame advance less obvious.
If there isn't an easy way to resolve your question, we may need some lateral thinking.
Is subject matter something like, sport, hummingbird etc.?
Dave.
P.S. Is this for the intro of a remake of a film named after you?
Thanks Dave I'll give it a try.
Regarding the name. Sorry can't divulge that information,
I'm working undercover. Would have to shoot you 'fraid !!
Aha - so it's 'bullet-time'.
This is the name used in the making of The Matrix for their exxxxxxxxtttttrrrreeeemmmeeee slow motion.
Dave.
how then
is it that I've seen a lot of adverts and even on films whereby
the movement is seriously slow, yet there is no judder in the
movement? Is it because they're using better cameras?
In brief... yes. :)
Specialist film cameras can shoot at many times 25fps, so when shown at 25fps super slow motion effects are achieved, that's how you see the car crash test analysis, for example. There are some video cameras which can record at higher than standard frame rates, but it's more difficult.
Have you seen the effect where the camera appears to track around an object frozen in mid air, or in slow motion? For that an array of still cameras are employed, their shutter timings all remotely and accurately controlled. Set off a circular array of camera shutters all at exactly the same time, play the frames as a video sequence, and bingo, a track around a frozen object!
But it's more expensive than an XM2. :)
Wonder if they use 25 cameras for that effect?
Pretty sure it's a lot more - obviously depends on how long the screened shot is to be, and you need 25 cameras per screen second. It's a while since I read about it, and I haven't got the link, but I seem to recall it was more like 100. As I say, a lot more expensive than an XM2!
There are obviously variants that can be achieved - stagger the shutters by 1/25 second for the first 25 cameras, then progressively shorten the delay, then fire the last 25 cameras all together for example. So a constant speed track round the subject, which gradually slows down, and freezes for the last second whilst the track continues. But it don't come cheap! :)
Goldeneye, you say you edit a lot of film using slow-motion. You mean film? Celuloid type film? Or do you mean you're trying to slow down conventional video footage on the PC?
Dave's technique works well, stacking one-frame-displaced tracks hides some of the judder. But if you're replaying DV tape, you may find the camera itself has a very smooth 1/3rd replay speed, and you can feed this into your computer and I bet you find it a lot smoother than Premiere's slo-mo for instance.
I use the Canopus Speed Control facility and this gives the smoothest slo-mo I've seen. At very slow frame rates you can actually see it doing a dissolve between individual fields in an effort to give you smooth footage from so few (50 per second) original fields.
tom.
Why not do it in post? Dynapel's excellent 'slowmotion' is incredibly cheap!
Its just DVfilm shot in the XM2 and imported into premiere 6.5 that
I'm using Tom. I didn't appreciate that there were different bits of software
that brought better results in this area, but maybe a combination of
Daves technique plus using either Canopus or Dynapel would work a treat.
I wasn't familiar either Tom with the replay speed being able to be
reduced on the XM2. Once again I have plenty of ideas to try out.
Thanks guys.
Arthur,
Looked at Dynapels slowmotion software and looks very interesting.
I'm going to download the demo to try out. How would I be able to use
this in conjuction with Prem 6.5? Would I have to export the clips I want
to slow down from 6.5 into Dynapel, and then re-import them into 6.5 again
once treated?
Also, did you buy your software from their american website (its about $17)
I've only recently 'found' the slomo prog, when looking for steadyhand.
Try here:
https://www.softwarehouse.de/cgi-bin/product/P12182
I don't use Prem (MSP 7) No plugin as far as I know, so not as convenient, :( but definitely superior slomo :)