Dec 23, 2012, 12:58 PM
Registered User
United States, CA, Ventura
Joined Aug 2007
757 Posts
Basically you get more motion blur with lower frame rates, giving the shots a more "realistic" look. The lower the frame rate, the slower your camera needs to move. A fast pan at 24p will make people sick, whereas the same pan at 60p will make people less sick. Your shutter speed should also be at double your frame rate to match the motion blur. 24p at a 200th of a second looks like saving private ryan movie.
I've found that shooting in 60p helps a lot with vibration and the innate movement of our camera platforms. If your shooting from a tripod, that is a different story all together

Quote:
 Originally Posted by SeismicCWave >>Use Frame Blending: on (Since I shot in 60p and output in 24p)<< I know this is getting pretty far off topic but I do have a question about frame rate for digital video. I kinda get an idea about recording frame rate and I am starting to understand the bitrate idea. I know they are not the same thing. So for some of the "better" video recording devices such as camcorder, Sony NEX series cameras, GoPro Heros etc. etc. They all claim a certain recording frame rate such as 60i, 60p, 30p, 24p etc. Let's assume I understand the 1080 meaning 1080 pixels across the image on the wide side. Let's also assume "i" means interlace and "p" means progressive and that is another topic. Then those numbers such as 60, 30 and 24 simply means the number of frames per second, correct? So for a "motion" to appear you need to "show" or "flicker" at least 16 images per second before the human eye can perceive seeing motion. It is because our human eyes can retain a latent image for 1/16th of a second. The cinema projector play a movie at 24 frames per second. That's why they call 24 frames per second the "cinema" rate. The higher end camera claims to record up to 60 frames per second which is great. Now when I do, iMovie cannot interpret my AVHCD when I record at 60p. So I use something called Clip Wrap to convert it to 30 frames per second. My question with this long description is that what is the difference in playback between 30 frames per second and 24 frames per second. It seems like such a small difference. So why not just play back at 30 frames per second instead of using 24 fps? Is there an advantage to using 24fps? It was so much simpler back in the film days.
Dec 23, 2012, 12:59 PM
Registered User
United States, CA, San Diego
Joined Apr 2012
752 Posts
Quote:
 Originally Posted by SeismicCWave >>Use Frame Blending: on (Since I shot in 60p and output in 24p)<< I know this is getting pretty far off topic but I do have a question about frame rate for digital video. I kinda get an idea about recording frame rate and I am starting to understand the bitrate idea. I know they are not the same thing. So for some of the "better" video recording devices such as camcorder, Sony NEX series cameras, GoPro Heros etc. etc. They all claim a certain recording frame rate such as 60i, 60p, 30p, 24p etc. Let's assume I understand the 1080 meaning 1080 pixels across the image on the wide side. Let's also assume "i" means interlace and "p" means progressive and that is another topic. Then those numbers such as 60, 30 and 24 simply means the number of frames per second, correct? So for a "motion" to appear you need to "show" or "flicker" at least 16 images per second before the human eye can perceive seeing motion. It is because our human eyes can retain a latent image for 1/16th of a second. The cinema projector play a movie at 24 frames per second. That's why they call 24 frames per second the "cinema" rate. The higher end camera claims to record up to 60 frames per second which is great. Now when I do, iMovie cannot interpret my AVHCD when I record at 60p. So I use something called Clip Wrap to convert it to 30 frames per second. My question with this long description is that what is the difference in playback between 30 frames per second and 24 frames per second. It seems like such a small difference. So why not just play back at 30 frames per second instead of using 24 fps? Is there an advantage to using 24fps? It was so much simpler back in the film days.
I really think it's just for that "cinema" feel. I also think that since your bitrate will be the same, there may be a bit more detail at 24p vs. 30p, but I am not sure on that.

That being said, the Hobbit was played at 48fps, so maybe this lower frame rate thing is going away.
Dec 23, 2012, 01:49 PM
AMA 46133
Hawaii
Joined Feb 2003
6,579 Posts
Quote:
 Originally Posted by MauiNate Basically you get more motion blur with lower frame rates, giving the shots a more "realistic" look. The lower the frame rate, the slower your camera needs to move. A fast pan at 24p will make people sick, whereas the same pan at 60p will make people less sick. Your shutter speed should also be at double your frame rate to match the motion blur. 24p at a 200th of a second looks like saving private ryan movie. I've found that shooting in 60p helps a lot with vibration and the innate movement of our camera platforms. If your shooting from a tripod, that is a different story all together
Thanks, that's what I thought but some of these new digital video thing is counter intuitive for me.
Dec 23, 2012, 01:52 PM
AMA 46133
Hawaii
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Quote:
 Originally Posted by jcmonty I really think it's just for that "cinema" feel. I also think that since your bitrate will be the same, there may be a bit more detail at 24p vs. 30p, but I am not sure on that. That being said, the Hobbit was played at 48fps, so maybe this lower frame rate thing is going away.
Well I am sure the old time silent movies were probably at 16 fps. That's why we can see the flicker. I think for the cinema the frame rate may be a budget constraint. It may be very expensive to go from 24p to 30p or as you mentioned 48p. With the movies being filmed more and more digitally maybe the frame rate will go up also.
Dec 23, 2012, 02:20 PM
Registered User
United States, TX, Seguin
Joined Mar 2005
619 Posts
Quote:
 Originally Posted by SeismicCWave Well I am sure the old time silent movies were probably at 16 fps. That's why we can see the flicker. I think for the cinema the frame rate may be a budget constraint. It may be very expensive to go from 24p to 30p or as you mentioned 48p. With the movies being filmed more and more digitally maybe the frame rate will go up also.
Old silent movies have flicker because they are variable frame rate...they vary based on the skills of the guy cranking the handle!

(ok, that may not be the only reason...)
 Dec 23, 2012, 02:24 PM Registered User United States, CA, Ventura Joined Aug 2007 757 Posts Also, remember that with the nex cameras, 24p and 60p have the same bitrate. Meaning that in 60p you are actually getting half the bitrate per frame of 24p because you are capturing twice as much information So the 24p is more detailed, but you need very smooth, slow motion to make it look right.
Dec 23, 2012, 02:27 PM
Registered User
United States, TX, Seguin
Joined Mar 2005
619 Posts
Quote:
 Originally Posted by MauiNate Also, remember that with the nex cameras, 24p and 60p have the same bitrate. Meaning that in 60p you are actually getting half the bitrate per frame of 24p because you are capturing twice as much information So the 24p is more detailed, but you need very smooth, slow motion to make it look right.
Yup, like I said, it's complicated.
Dec 23, 2012, 02:28 PM
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United States, CA, San Diego
Joined Apr 2012
752 Posts
Quote:

Cool, thanks for the detailed explanation. The more you know...
 Dec 23, 2012, 02:46 PM Pants first, then shoes Joined Jan 2011 2,861 Posts Thanks guys for the AVCHD converter suggestions, appreciated. Great info on frame rates etc. One thing that has me confused is the shooting at 60fps and then converting it down to 30fps to get a nicer look. Im on a mac and using FCP X or iMovie. With iMovie I dont understand how to do the conversion down to 30fps. It usually tells me the frame rates dont match and the only options are the lower frame rates. What is it Im missing in this?. Cheers
Dec 23, 2012, 02:48 PM
AMA 46133
Hawaii
Joined Feb 2003
6,579 Posts
Quote:
 Originally Posted by mattchase Nate covered it pretty well, it is a complicated combination of frame rates, shutter speeds, bitrates, lighting, and what is being filmed that all add up to the final look. One thing I will say is that you will pretty much always want to shoot progressive for the best quality, and at the highest bitrate you can. Interlaced footage can look fine, but it will show some ugly side effects of it being interlaced. So any camera that tries to make a big deal of it shooting a 60i frame rate annoys me, it is no more useful than a digital zoom (you know what 60i actually is? 30p)......... ...........I also think it is a bit of a misnomer that 24p gives a "cinema" feel, it's more complicated than that. It is just one of many different factors that go into creating more of a cinema look to footage. As for 48p, I haven't seen The Hobbit yet but don't think that frame rate will be replacing any others in the near future. It's just another tool that can be used to create a different look, which may or may not be what you want for any given shot.
Whoa Matt! That's a lot of very good information. I am saving it to read over again and again. I am pretty much a still image photographer all my life. I only dabbled in movies with a 16mm Bolex and now a bit in digital videos.
Dec 23, 2012, 05:52 PM
Navarre, FL
Joined Mar 2002
3,858 Posts
Quote:
 Originally Posted by sdaudet Hello I need help i build a rusty camera mount but i would like be sure about the solder on the potentiometer Some body could say me where is the positif and the negatif on the rusty potentiometer It is the red in midle. And invert the black and white if it turn in the wrong ? Thanks a lot
Sorry, but my first answer to this was wrong. I don't know what I was thinking, but here's the corrected answer (and I edited the original post).

The original servo pot has three wires, almost certainly in a row. The center wire from the original pot goes to the center connection on the external pot. The outer two wires go to the other two connections on the pot, and it's essentially trial and error. If it doesn't work correctly, reverse the two outer wires on the pot.

I should have just referenced one of Hansen's earlier answers to the question, since it would have been correct

Rusty
 Dec 24, 2012, 10:57 PM AMA 46133 Hawaii Joined Feb 2003 6,579 Posts The latest tinkering: I just fitted one of those black square plastic pot that was from the inside of a servo to the tilt axis on the camera gimbal. Once the glue dries I will take some pictures to show you. It saves a few grams.
Dec 24, 2012, 11:07 PM
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United States, CA, San Diego
Joined Apr 2012
752 Posts
Finally finished and tested the gimbal:

hitec 7940th x2, HoverFly Pro as controller.

I had a short flight at night with a GH2, but I will generally be flying with a T2i. I probably sized it larger than most. First flight looked good, but I need to tune the reaction a bit.

Overall, really impressed with this design. Way to go Hansen and rusty!