Rabbit
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Post by Rabbit on Feb 25, 2017 11:11:23 GMT
With TV pictures Syd, half of the picture is sent 50FPS. So it's actually 25 full FPS. Progressive scan is showing the whole picture in one frame at a time rather than half. The half picture trick is called interlaced, which can show odd artefacts on movement and pans. Diagonal lines can also be a problem.
It's better to use progressive scan with its full frame picture and most tv' s now play progressive scan. I'm not quite sure what my software is doing to my old 25FPS footage. Looking at it, it's slightly choppier when rendered at 25 progressive rather than at 50 which seems to look better. So I'm sticking with 50.
It also helps movement to shoot at double the frame rate. So I use 50fps, so need to shoot if I can at 100th second shutter speed. That's where neutral density filters come in really handy. At least then, judder is at the least offensive on the source.
It's quite complex and flaws show very clearly on modern 55 inch LCD TV's. They're pretty unforgiving. Some have a 'smoothing' option on the TV menu, but I prefer to get the source as smooth as I can first.
When you first do a rip, it's very easy to overlook the judder on movement because you're so pleased you actually got a copy of your old footage!! I now look very carefully at left/right movement and edges on pans for signs of judder. On a big TV, it's very distracting.
What surprised me was the bitrate. On music, it's way less obvious but video shows the difference right in yer face!! After seeing the effects, I go for the highest bitrate I can every time.
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juke
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Post by juke on Feb 25, 2017 23:40:34 GMT
Ah, that's the story behind 1080p and 1080i etc. I knew the 1080p is the one to go for if possible but never looked for an explanation.
Your post above explains it simply.
Syd
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Rabbit
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Post by Rabbit on Feb 27, 2017 16:31:51 GMT
I've got some proper rules fixed in my head now for good edits.
a) If you take footage at 25FPS on the camera, try to set the shutter at double.... 50th second. (Helps to avoid movement judder) I use 50fps at 100th sec. b) If you use an editor, edit in the same frame rate and also render at the same frame rate or double. (I tried rendering 25FPS at 50 and for some reason, it might be slightly smoother) c) Neutral density filters are useful for keeping the shutter speed where you want it. I have a variable one which is excellent. d) Render at a higher bit rate if you want DVD quality video. e) if you can't use a neutral density filter, don't pan the camera in bright light. (Causes judder due to very fast shutter speed) f) If you can, turn off the sound on the camera during editing and replace it with ambience from say, YouTube. (I record my own on a digital recorder) This gets rid of clunks, wind noise and anything else due to you holding the camera) For speech, I turn the camera sound up at that point and merge it in with ambience. (I fade it in and out so it doesn't notice. Also eq it it with a bit more treble to cut through)
Be en really getting into some experiments last week and it has really paid off with the quality that I can get from both my Sony camera and the GoPro Hero 5 which is an amazing little camera.
Maybe I'll make a spoof film and review a headphone using the quirks of other reviewers........
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Deleted
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Post by Deleted on Mar 3, 2017 15:35:59 GMT
I've got a strange issue with videos made on my phone. I have a windscreen mount and there's a strange wobble throughout the video. I first noticed it last year in Spain but I put it down to the heat at the time. I've just been out & shot 7GB and the wobble is still there. It's not hot. The software I was using (Final Cut Pro) seems to not enable stabilization for this particular file type (MP4) which is bizarre so I've downloaded the trial version of Adobe Premiere Pro to see if that can fix the issue. If not then I think I'll either have to invest in a dedicated mount or a new camera like a GoPro or something.
Has anyone got any experience with Adobe Premiere?
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Rabbit
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Post by Rabbit on Mar 3, 2017 16:21:30 GMT
If it's like this .... It could be because the camera has a cmos sensor. Maybe a better mount might help to stop it? It is normally caused by the fact that the camera takes pictures in progressive scan so the bottom line is at a different time to the top, so the image wobbles because each frame is a composite of very slightly different times. The processor on the camera is a bit slow to sort out scans at the speed you're moving. Especially with the dashboard wobbling about as well. For general use, I set 50fps and lock the shutter to 1/100th, but for in car, a bit of experimenting might be needed for proper smooth footage. (Motion blur can help smoothness though) If the camera doesn't have those kinds of control, then there's not a lot you can do probably. Rolling shutter is most likely. Many cameras use cmos whereas Ccd sensors record the whole image in one go, rather than line by line. The only thing is though that a rolling shutter gives a better dynamic range and works better in low light that a CCD sensor. One way around it is a much better mount that helps sometimes to cushion movement. This might well be what you're getting... CMOS and Rolling ShutterIf your camera can do it, set it to 50fps and try a slower shutter speed as well ....... The motion blur might disguise it. Experiment with shutter speed or try sticking a neutral density filter in front of the lens to force a slower shutter speed. If you haven't got neutral density filters, just as an experiment, try sunglasses!! I think some cameras are more prone to it than others unfortunately. The GoPros also have a CMOS sensor. Try this tutorial ... Just realised that you took it on a phone. It is most likely to be a rolling shutter problem. Try this? iMovie
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Deleted
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Post by Deleted on Mar 4, 2017 16:11:27 GMT
Thanks for the feedback Ian & I'm sorry it's taken me so long to respond. I keep forgetting I need to manually subscribe to threads in this forum. My bad. Anyway, I had completely forgotten I had iMovie installed so that's a timely reminder. It's certainly a lot easier to use than Final Cut but, to be fair, that's aimed more at the professional end of things. I'm pretty sure the issue is to do with Rolling Shutter but although there's a tool in iMovie to deal with that it just doesn't work. The program just seems to hang although the pinwheel suggests it's still working. I initially thought the problem might be that the video clip was too long at 33 minutes so I've experimented by cutting it down to 13 minutes but it makes no difference. Kinda stuck now to be honest. You may have seen another video I posted on YouTube. That went really smoothly. I had no rolling shutter issues but it was filmed using my Panasonic FZ150 balanced on a pillow on the dashboard. Seriously Have you got any idea how long it should take to analyze a file? Is it real-time? Or faster/slower?
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Rabbit
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Post by Rabbit on Mar 4, 2017 16:30:37 GMT
With a 7Gb film Gordon analysis will take a very long time. Especially if it's hd.
Once I've compiled a film I set up an HD render and honestly leave the computer all night. That's for about 30 minutes of hi res film.
My computer isn't that fast though, but I reckon to multiply the length of the film by about 8 or even 10 to be on the safe side in my case. So a 30 minute film would take 5 hours to render. 15 minutes around two to three hours? It's seriously slow.
Probably, a Mac might be quicker since they are better with graphics but it's a very slow process. It may take twice as long almost if the programme analyses and then asks for the go ahead to render it.
I have an adjustable image stabilisation section on my editor that analyses and then stops and waits for you to give it permission to render. My guess is that's what iMovie might do.
Leave it running overnight and in the morning, you might have either a video or the programme asking whether you want to go ahead and render. Sometimes they leave the original in one window and the corrected version in another next door for you to compare before rendering.
Rolling shutter problems are very tricky but as you've found, just a cushion to stop all the mini vibrations helps to alleviate it. Problem is that not only is outside moving fast, but the car is also rattling at a very fast rate which is why the shutter records wavy lines because to the lens, that's where they were when the shutter opened. It's actually not a fault, but can be due to a slower processor on the camera as well.
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Deleted
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Post by Deleted on Mar 4, 2017 16:39:53 GMT
Ah, that's reassuring. I knew the program wasn't actually hanging because I can perform other tasks within it. I just hate pinwheels & progress bars since they so often bear little resemblance to what's actually happening. Thanks for that mate, I'll set it up to work overnight tonight & see what happens.
In the long run though I guess I need to look into other camera options. Like I said, my Panny doesn't seem to suffer from the Rolling Shutter issue - although it does use a CMOS sensor - so that's my best option at the moment. The trouble with that is it's a bit coumbersome for indscreen mounting. I've been looking into action cams and although GoPro is out of my financial reach, Drift aren't, and the reviews seem promising.
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Rabbit
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Post by Rabbit on Mar 4, 2017 17:25:26 GMT
The Panasonic is a good camera Gordon, with a terrific lens. The processor is quite speedy so rolling shutter might well not happen so easily. It is a pain, but eliminate the in car rattling and it can be better with cheaper cameras.
I get the equivalent if I use a digital sound recorder in the car. If I use the inbuilt mics, there are loads of minute vibrations that totally wipe the sound out, so I have to use a Rode directional mic on a stand if I want to add speech in a car!! Such a faff.
Be careful with cheaper action cams though. Same thing. Slow processor so rolling shutter will happen. Also, many hide the fact that they only film in 30fps. For tv, you want 25 or 50 and these cheaper ones can't be adjusted. I have one and took some footage in Florida in a swimming pool. (Underwater shots as well) Two problems that caused judder ....
a) couldn't change from 30FPS from 50. b) no shutter control, so because of very bright light, too fast a shutter speed which = motion judder. Nowhere on the camera could I fit a neutral density filter in order to reduce the shutter.
The picture is dead sharp, but motion is shite. Wrong frame rate and too fast shutter screwed it up.
The most useful filter for movie is my variable neutral density filter in order to ensure that the shutter stays at 100th with 50fps. Always a ratio of 2:1 gives a shutter angle of 180 degrees (it's called that because each film cycle is 360. So shutter open for 50% of frame time)
The cheaper action cams just give no control and you have bright light there in the Summer to speed the shutter up too much. That will cause film judder. Judder with rolling shutter will make you seasick!!
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Rabbit
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Post by Rabbit on Mar 9, 2017 21:27:52 GMT
Found a better alternative in Sony Movie Studio. The way it works is a steep learning curve and less fancy than the other programme, but hidden inside are some very sophisticated tools that have made some of my videos just pop out of the screen.
It has an unsharpen mask and a sharpening tool. This literally takes the lens away. On screen, it's like looking through a crystal window. You can up saturation, but also choose where in the colour scale that you focus the addition. Result is that the picture can become amazingly vibrant. You can tilt video so the horizon is straight as well as cut in to reframe shots.
And loads more.
The problem is that this one is more like a photographer's tool and so is way less user friendly. You need to know more of the technical stuff to know what it is doing and the choice of rendering is huge. Get the rendering wrong and your film looks totally messed up on screen.
I have about eight hours of footage from Florida last year that I'm cutting down to around half an hour. Not only is the film more snappy, but its sharper and pops really well.
I haven't edited it all yet but getting there.
With big projects, I cut them down into around 3 or 4 minutes sections and keep all the templates as separate entities. This makes a bigger project much easier on the computer.
The end part is opening all of the templates to copy and paste them into the right order for the final film and add any music necessary. (Plus getting the stitching done nicely between each template) It can be an organisational nightmare so you have to be really tidy in your filing and meticulous in checking each short render before making the final film.
The final one will take a very long time to render in HD since all the sharpening and contrast adjustments take a long time for the computer to sort out, so it'll be on lock down for a couple of days I reckon.
I have found hidden ways of speeding up the render as well. Sony Movie Studio takes much longer than other programmes to render. However, the results are superb and crystal clear with no added flicker or framing speed problems.
What I like about this one is the quality of the results. I played back some of the short prepared sections on a 65 inch TV today. (Not mine) My mate was gobsmacked at the quality. He felt better than broadcast in places. So sharp, that at one point in the editing, I saw pin sized blobs on the screen. I thought pixels had gone out or there was something on the lens, until I moved forward frame by frame in the editor and realised that they were birds in the distance!!!
I may make a little film about some headphones sometime soon just for a lark. Worth watching just for the quality let alone the headphones. Might do the Trinity Audio stuff.
Anyone really interested in film making and getting them to look professional must take a look at the editing options. There are a lot of really poor ones around that look good on the face of it, but render terribly. They're kind of designed to attract people to them with all the fancy options, but they let you down on the crucial 'unseen' part ....... getting a perfect render, which takes a serious amount of computer power and a very long time with multiple passes if you want a proper, professional look. That means a bit more in depth understanding about frame rates, shutter speeds while filming and its effect, and rendering options for the viewing device.
Big TV's have made this more of a challenge for home users as my old videos have painfully showed although I have been able to rescue and even improve the 'look' of most of them in the end. Resolution isn't improved, but the impression of sharpness has been dramatically changed for big screens.
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jello
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Post by jello on Mar 10, 2017 14:13:48 GMT
Home videos you say? Nudge, nudge, wink, wink. A nod's as good as a wink to a blind bat
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Deleted
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Post by Deleted on Mar 10, 2017 18:25:26 GMT
My video didn't turn out good at all unfortunately although the Rolling Shutter fix in iMovie did work after I'd left it on overnight. Unfortunately it's made it even worse. I'm now not convinced that was the problem in the first place. I'm going to try to find a more solid mount for my Panasonic; something that uses it's tripod socket would be ideal.
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Rabbit
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Post by Rabbit on Mar 10, 2017 21:31:06 GMT
You dirty beast Mark. Judder is the biggest problem.... portraying smooth movement!! Rolling shutter is a pita. It's not something that can be easily fixed and most fixes are just a compromise. If I get motion problems, I cut out the better stuff and fade them into each other. Funny thing is that the motion smoother on the GoPro outperforms my Sony. I tried it in my car on a mini tripod on the dash and it was pretty amazing tbh. I have no idea why that should be because I didn't set up anything special at all. Perhaps the GoPro is built more with the idea of running around like a looney while filming? Just to give you an idea Gordon of times for HD rendering ...... I've just finished editing a film down to two twenty minute sections. The first render has just been started on a standard laptop. 8 hours for 20 minutes video. The programme takes a long time because it's also changing things like contrast, size of picture and colour corrections etc, so it has to be applied first before the actual render. So it goes on for the night and hopefully in the morning, I'll have 20 minutes of clean footage. I dread to think how long 4K would take.
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