frame rates

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iCEbLuEORbitZ
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frame rates

Post by iCEbLuEORbitZ »

ok, i want a new camera, although it probably wont happen, but just incase, i dont understand something. i know that a lot of cameras have frame rates of 60i (i kno that records 2 sets of 30, each record either upper or lower feild) then there is 30p and 24p. i know what all that is. now, there are shutter sppeds of 1/60-1/15000. i dont understand how that works if it only records 60 frames per second. is that how fast each frame is taken? but i have heard that some cameras have different shutterspeeds so u can do super slomo and stuff. please explain thanks!
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RE: frame rates

Post by reflexive_cinematics »

Right. Most cameras are set at between 60 and 100. I set my shutter to 30 and that gives a little bit of motion blur and it's very subtle. Anytyhing less than that and you will get jerky. For shots i know i will make slowmo later, I will set my shutter as high as 1000. ( i've actually shot somethings as high as 4000 -5000 though hehhe. that was a lighted water fountain so that's how I got away with that )
The higher shutter speed will get rid of the motion blur, which will allow you to, in post of course , seperate the interlaced fields of each frame and make a whole one out of the half. so you end up with 60p basically. 60 frames per second looks a hell of a lot better in slow motion and will allow you to go even slower with out being jerky
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iCEbLuEORbitZ
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RE: frame rates

Post by iCEbLuEORbitZ »

i dont understand. basically the faster the shutter speed the less motion blur, i get that since i'm big into photography. but i dont understand how you could separate the feilds to get a full frame from just half of the picture, or 1 feild?
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BrownCowStudios
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Re: RE: frame rates

Post by BrownCowStudios »

iCEbLuEORbitZ wrote:i dont understand how you could separate the feilds to get a full frame from just half of the picture, or 1 feild?
Effectively, you're just separating the fields, and doubling each set of fields to create two whole frames from one interlaced frame. It's a loss in resolution, but you will undoubtedly achieve smoother slow motion.
Erm... yeah...
iCEbLuEORbitZ
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RE: Re: RE: frame rates

Post by iCEbLuEORbitZ »

ok i understand that now. but the other day i was messing around w/ my friends new xl-2 and i was changing the shutter speeds, and the higher i went the darker it got, which makes sense, but when you set it to say 1/1500, on 24p mode, does that mean that its recording 1500 frames on the tape in one second, or just 24 frames at 1/1500 per second. the only thing is that if you did do a shutterspeed that high and it still only records 24 frames taken at 1/1500 each second, then wouldnt it have a weird strobing effect since each picture would be on there for sucha short time, then there would be blackness inbetween each frame? or if it took the picture that fast, then did like a framehold until it takes the next, but i still dont see how that would help slomo since your still only taking 24 frames each second, it wouldnt allow you to make it slower w/o being choppy, it would only make each frame be less blurry. i'm soo lost i just dont understand whats going on here. please help me!?
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bretoncrackers
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RE: Re: RE: frame rates

Post by bretoncrackers »

your friend's xl-2 would still be recording at 24 fps, and the 1/1500 per second is the rate at which the frame refreshes. in short, if you have a really slow shutter speed, like, 1/4 of a second, then shutter stays open for 1/4 of a second, meaning that one frame will contain the information of 1/4 of a second of motion and action (it will be really blurry) and 6 of the frames will be the same (1/4 of 24). Once your shutter speed is higher than the frame rate, (anything over 1/30 of a second, or in your case 1/24 of a second) it only serves to make the image crisper. For slow motion shots, id suggest newhere from 1/150 of a second to 1/500 of a second shutter speed.
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RE: Re: RE: frame rates

Post by iCEbLuEORbitZ »

oh ok thanks. so thats why in the matrix and stuff they have to use cameras, because to get that slow, it would be choppy if you slowed down video footage that far. but i did once see a skate video where he did a kick flip in super slomo, like it lasted 6 or 7 seconds. and it wasnt choppy.. any ideas on how they did that?
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RE: Re: RE: frame rates

Post by bretoncrackers »

they used software to create frames in between to fill the gap OR they used a higher frame rate (film cameras can shoot at just about any frame rate, but it's expensive to shoot at high frame rates, but looks nice) I saw a clip of a guy shooting a bullet into a pane of glass where a mile of film was fed through a camera in 3 quarters of a second and then slowed down. It looked incredible. For your kick flip, they might have done it at 50 to 100 fps.
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RE: Re: RE: frame rates

Post by iCEbLuEORbitZ »

whahah wow. thats awesome. too bad i dont have 50 thousand dollars to spend on film, and the proper tools. haha. yea i know for the matrix they decided to do cameras set up around the actors and they just took pictures milleseconds after the previous, and then filled in th gaps w/ software.
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