AG-DVX200 4K Large-Sensor Handheld Camcorder

As I said, I shot a 59.97 because that is what is offered by the camera..and I did adjust the shutter to 120! I did it deliberately after reading Barry's earlier post. I thought you were supposed to do that? Of course, Vimeo won't accept 59.97 and converts it down. What should I have done in this instance? He, the conductor, wanted video of him conducting so I chose the higher speed to capture all the movement. He also wanted something he could edit himself. He doesn't have a computer capable of handling 4k which is why I switched to AVCHD. He wanted the cards from the camera when it was over. I double recorded as a back up and to see what the results were. Can I fix my version so it doesn't look staccato? Should I have shot in 23.97? and raised my black gamma to zero.

I also have him in rehearsal. He is wearing a faded pink shirt and black jacket. The shirt had a white collar. Under the lights, the pink shirt almost looked white, but the camera did a good job of picking out the color. I can post if anyone is interested.


I don't mind the picking apart...I learn something every time :)
 
I would have left the shutter at 1/60. Not that there is anything inherently wrong with 1/120... when I shot PAC-10 (Now PAC-12) sports, I shot in 1/120 all the time, precisely for that effect (plus it help produce a bit sharper image... we were shooting standard definition NTSC 29.97 fps).

Back in the good old days (Lord I sound old), when everything was NTSC 29.97fps interlaced, shutter was at 1/60 because interlaced video was basically two half frames merged into one. It was necessary because of the nature of NTSC video. With 24p, keeping the shutter at 1/48 or 1/50 helps keep down on the motion blurring that can happen from the slower framerate, producing a bit sharper image while still maintaining the cadence of 24p. But with 60p (59.97), a shutter of 1/120 means the shutter is still closing twice per frame during what is already a pretty high framerate. The high framerate itself helps keep motion blur down, so reducing it via shutter speed isn't really necessary.

Again, it's "wrong" only in the sense of what one's desired aesthetic taste is. If you prefer that staccato look, more power to you.
 
Temporal motion of NTSC 29.97fps interlaced and progressive 59.94 is the same as the number of exposures the camera is taking is the same. Fields in one case ( half vertical resolution ) and full frames in the other. Since the CRT's etc needed to know when the field sequence started the frame sync and time code increments every 2 fields. Fields don't get merged together but get displayed one after the other. A CRT needs it this way but a LCD etc needs to have that deinterlaced into a progressive image at the refresh rate of the display ( normally a multiple of 60 in NA ) how this is done is important to how the video looks too. High quality deinterlaced is just as good as progressive. That in my mind is why getting a display with a refresh rate of 120 or above not only allows for good deinterlacing but also true 24P playback since having a refresh rate of 60 means that 24p has to have a pullldown cadence to display so not really 24p playback as one would see in the theatre. Value to me of shooting 60P is being able to get a nice still capture from the video especially in UHD. I like smooth video so tend to shoot at 1/60 in 60P or 60i depending on which camera I am using. The video from Vimeo almost looked like it was being played back at 30P.
 
that's what happened....Vimeo doesn't allow 60p. If you upload in 60p, it converts it to 30p. So, can I do anything in post to achieve a better look in Vimeo?
 
My workflow is to pretty much shoot everything in 60p, 1/60th shutter. I then decide my output and choose my NLE project settings based upon this decision. So if I want a 24p finished product I edit the 60p footage on a 24p timeline. So the thought process is based upon acquisition and delivery as being two separate choices.

This is my video workflow for normal shooting. If I am shooting an interview I might shoot in 24p 1/48th shutter. The 120th/esc shutter in your video is the main source of the staccato movement, not the 60p/30p. 30p without camera movement will look smooth, especially on a computer monitor. I am not throwing stones :) The footage has nice qualities.
 
... a shutter of 1/120 means the shutter is still closing twice per frame during what is already a pretty high framerate.
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Would it be more accurate to say the number of times the shutter is effectively closed is determined by the frame rate... in this case 60fps, but that it only remains open for half the time the frame is being recorded?
 
With 60p at 1/60 shutter, the shutter is basically never closed, it's always open. It's open for the full duration of the current frame, and it'll be open for the full duration of the next frame, and there's no gap in time between frames, so it's basically always open. This is, and has always been, the standard in video cameras for delivering the "live" or "looking through a window" video look.

With 60p at 1/120 shutter, the shutter will be closed for fully half of the frame time. It's not that it opens and closes multiple times during the frame, it's that it cuts the duration short, to about half. All high shutter speeds work that way; they never open and close multiple times during the frame, they just spend more and more time closed during each frame.

60p at 1/120 is not a normal video look and generally should not be used for shooting "live" video without understanding the side effects. 60p @ 1/120 would be suitable for someone shooting film-style at slow motion, but for shooting "live" footage it will make the video look unnaturally staccato. Now, sometimes you may want that (as Mike Harvey said, he chose it specifically to make for crisper action). If it's done intentionally with a certain aesthetic in mind, then sure, go ahead. But if you're shooting normal footage that you want to have look like the type of video footage we've all been watching for the last sixty+ years, then no, you do not want 1/120, you want 1/60.
 
Barry_Green said:
In terms of motion rendition, high-quality de-interlaced 60i will be the same as 30p. But de-interlaced will always be much lower resolution than true progressive.
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Not true. Certainly for my Sony 240Hz TV which in fact ups the frame rate even more to its refresh rate by interpolating the missing information. There are also several other Bluray players which upscale interlaced DVD that are also full 60P to the TV. They in fact use multiple fields and interpolate the missing fields retaining the exposure rate of the camera that is the same whether 60i or 60P. That is why the audio has to be delayed to allow for the delay needed for processing. I cannot tell the difference on my Sony 240Hz TV playing back 60P or 60i from my cameras. Either directly with HDMI or from an edited file. Is it as sharp as a true progressive image with very rapid movement? Maybe not but it indicates there is a big difference between how the image is de interlaced. De interlacing a 60i image should stay at the exposure rate which is the same for 60i and 60P to de interlace to 30P indicates a very bad system destroying the motion that was intended. NTSC 29.97fps is not 30P it is the frame sync pulse and timecode rate not the exposure rate which is 59.97 fields per second the same rate as progressive 60P.
 
Ron Evans said:
Certainly for my Sony 240Hz TV which in fact ups the frame rate even more to its refresh rate by interpolating the missing information.
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Interpolated information is not resolved detail. Therein lies the difference. Interlaced video consists of 59.94 "half frames" per second. Progressive video would have 59.94 full frames per second. Interlaced video is, effectively, 1920x540p, if you want to look at it that way. Progressive video is 1920x1080p. There is more resolved detail in 1080p. This isn't a subjective opinion, it's the very definition of the two different systems.

Now, can you argue that some upscalers fill in the missing information so thoroughly that it's "just as good" as the original? Sure -- if you find it acceptable, then more power to you. But interpolation is guessing, it's not resolving. I am talking about resolved detail.

De interlacing a 60i image should stay at the exposure rate which is the same for 60i and 60P to de interlace to 30P indicates a very bad system destroying the motion that was intended.
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Well, that depends on the goal of the person doing the de-interlacing. Prior to the existence of progressive-scan video cameras, pretty much any and all discussion of de-interlacing was all about trying to get film-looking footage from interlaced video. That was the goal and the purpose of why people would try de-interlacing.

You're talking about something different here. I can see what you're saying, but for purposes of the discussion, let's start at the beginning: it is my contention that interlacing is evil. It is a form of compression that literally discards half the information that was recorded. Not only that, but it blurs out even more of the information, to smooth the interline twitter that happens when you discard half the information that should have been there in the first place. It is, finally, due to 4K, being discarded into oblivion where it belongs. It should have been discarded during the transition to HDTV, but the broadcasters weren't ready and Sony wouldn't allow it, they fought vigorously to keep interlacing alive. Finally, in 4K, there is no provision for interlacing, and only progressive imaging is allowed.

I can see very clearly what you're saying about upscaling blu ray players, etc., but let me just point out where that argument inevitably leads: why shoot on 4K at all, if upscaled blu-ray looks "just as good", "just as sharp", etc? Why shoot on progressive at all if interlaced looks just as good? Heck, there are upscaling DVD players, so -- does that mean we can go back to shooting on standard-def equipment? Won't it look just as good, once the 240Hz TV gets through scaling and de-interlacing it?

I think we all know that there are very real benefits to capturing more detail in the first place, rather than relying on some technical wizardry to fill in the missing gaps. Sometimes compromises have to be made because the technology simply isn't there yet to do what you want done (such as why interlacing was developed in the first place, or why 4:1:1 came about, or why Sony tried to push HDV as a standard, or why Panasonic used spatial offset sensors in the HVX200). But once the technology *is* there, then continuing to embrace seriously compromised footage and counting on technical wizardry to "repair" the initial damage, seems like an unwise course to me.

NTSC 29.97fps is not 30P it is the frame sync pulse and timecode rate not the exposure rate which is 59.97 fields per second the same rate as progressive 60P.
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NTSC 29.97 is most definitely not 30P, it doesn't look anything like 30P. It samples motion at 59.94 fields per second, which is the same sampling rate as progressive 59.94P, yes. But it only retains literally half the sampled information, it discards the other half.
 
Barry_Green said:
NTSC 29.97 is most definitely not 30P, it doesn't look anything like 30P. It samples motion at 59.94 fields per second, which is the same sampling rate as progressive 59.94P, yes. But it only retains literally half the sampled information, it discards the other half.
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Barry I agree with what you have said in your post but why then did you say de interlacing 60i is 30P. That is why I responded based on exposure rate rather than detail which I absolutely agree with. No amount of de interlacing technology can guaranty the interpolated data is what was actually there !!! Progressive all the way. I am not defending interlace or want to use it in the future. Which is why I am waiting to find something to upgrade to from my Sony NX5U as all my other cameras shoot 60P. Exposure rate is important to me as I like the smooth motion of higher frame rates. Hence my interest in following this thread on the DVX200 purely for how it performs UHD at 60P
 
Ron Evans said:
Barry I agree with what you have said in your post but why then did you say de interlacing 60i is 30P.
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Because, as mentioned earlier -- that was the whole purpose that people started de-interlacing footage for in the first place. They wanted to make filmlike footage from interlaced video.

I guess later we encountered folks de-interlacing 60i into 60p because they wanted to simulate slow-motion footage from a 60i camera; I should have mentioned that in the initial post.

I am unaware of there being any preference for folks to de-interlace 60i to simulate 60p for the "live" look. If anyone is doing that (other than, obviously, a progressive-scan TV that has to do it because it can't display interlaced directly), then I am not aware of it. But you're correct in that TVs have to do it, because the interlaced screens are gone, and interlaced displayed on a progressive monitor looks horrific.

Exposure rate is important to me as I like the smooth motion of higher frame rates. Hence my interest in following this thread on the DVX200 purely for how it performs UHD at 60P
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Totally understood and agreed. 4K/UHD at 60p is currently a rather rare animal. Perhaps part of the confusion is coming from the use of "exposure rate" vs. "sampling rate"; I'm used to referring to it as a "sampling rate". It took a couple of seconds of the penny rattling around in my skull before it finally dropped and I understood your meaning of "exposure rate" to be the same as "sampling rate" (meaning, 60 exposures per second).
 
Some suggestions for next firmware or do I miss something?

- focus assistant should be available also when rec is on. Or is it selectable in some where in menu? Now when I press "rec" the assistant disappears. I have seen pictures about demo cameras where there is red rectangle around the lcd during the focus assistant.

- low light mode can not be assigned to a user button. I suppose this should be used before the gain adjustment.
- flash band protection should be also assignable to user button ?
 
Ron Evans said:
Barry_Green said:
In terms of motion rendition, high-quality de-interlaced 60i will be the same as 30p. But de-interlaced will always be much lower resolution than true progressive.
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Barry I agree with what you have said in your post but why then did you say de interlacing 60i is 30P
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Until I got a new camera this year, I never have been able to think of any other way than use a different shutter speed, then de-interlaciung video, to create slow motion without ghosting.
I only ever want to do slow motion as a replay of normal video that has already been seen, not to have it instead of the normal video during a scene.
 
Barry_Green said:
It samples motion at 59.94 fields per second, which is the same sampling rate as progressive 59.94P, yes. But it only retains literally half the sampled information, it discards the other half.
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But..... field by field the lines are displaced - so (for a 1080 system) you do vertically get lines in 1080 separate positions. Which would seem to indicate it does indeed give full 1080 resolution, but......

.....it doesn't. Partly it's due to the way interlace chips scan (summing differing lines on differing fields) and partly due to what is loosely called the "Kell factor". (The theory goes back right to 1934 and the birth of television.) https://en.wikipedia.org/wiki/Kell_factor

As simply as possible, it defines a "Kell factor" (generally taken around 0.7) which defines how much the real vertical resolution in a system is lessened due to interlace, than number of lines would otherwise predict it to be. The Wikipedia link gives detail, but for a 1080 system the vertical resolution is given by (Kell factor)x1080, so 0.7x1080, or about 756 lines. Each field may only have a resolution of 540 taken one at a time - but it's wrong to therefore think the system resolution is only 540.

Barry_Green said:
Interlaced video is, effectively, 1920x540p, if you want to look at it that way. Progressive video is 1920x1080p. There is more resolved detail in 1080p. This isn't a subjective opinion, it's the very definition of the two different systems.
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No, that's not true. Interlace could only be properly called 1920x540p if the lines on each frame were in the same spatial position field by field. Which is not the case, the whole point of interlace is to displace them. It certainly *IS* true that 1080p has more real resolved detail than 1080i - but not by a factor of two. A good deinterlacer will actually manage to get something like Kell predictions out of 1080i - so something more corresponding to around 756p. No, not as much as 1080p - but a lot better than 540p.

Barry_Green said:
It should have been discarded during the transition to HDTV, but the broadcasters weren't ready and Sony wouldn't allow it, they fought vigorously to keep interlacing alive.
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I remember being at IBC when the debate about what format should be adopted for the European HD standard was the hot potato. My memory of that time was that whilst 1080i started off being the Sony standard, and 720p the Panasonic standard, by then both manufacturers (and others) were moving towards a position of their cameras being able to do both systems. I don't think the manufacturers had that much influence in the debate, and by that time were ready to simply supply cameras to whichever format was chosen.

It was actually the EBU that was strongly in favour of 720p/50, and a main plank of their argument was the compression advantages of a progressive signal. (Which is true enough.) But it was largely the broadcasters that wanted to go the other way, and the reasons are interesting. Part of the EBU argument was around research about what was "good enough" for given screen sizes, but screen sizes started to increase far quicker than they'd envisaged - the EBU thought they were no likely to get much bigger than 32-37" for home use for many years.

But most importantly, it wasn't simply a case of 1080i/25 versus 720p/50.

It was 1080i/25 *AND* 1080p/25 versus 720p/50. So adopting the 1080 system gave the option of a 50fps system with about 1920x756 resolution (via interlace) OR a 25fps system with full 1920x1080 resolution (via progressive). If 720p had been adopted, it would have been 1280x720 max - even for 25p material.

Yes, it would have been the best of both worlds to have 1080p/50 and 1080p/25 as a system, but the 1080p/50 simply wasn't a technical option at the time. (And is still problematic for uncompressed SDI transfer.) Waiting for 1080p/50 to become viable would have held up HD transmission by several years. Nobody really wanted interlace as such - but progressive and 50 Hz motion meant 720 resolution, end of story. And by going for 1080 it allowed for progressive when 25fps was desired, and just meant interlace when programming dictated 50fps.

Barry_Green said:
Finally, in 4K, there is no provision for interlacing, and only progressive imaging is allowed.
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And (nowadays) I will join you in being thankful! I'm not disputing that interlace NOW belongs in the past, and I think one extremely good thing about 4K is that it does indeed give a chance for such to happen. Let's all be in full agreement about such.

But was it ever "evil"? Certainly not in the 1930's, and was one of the big reasons why the EMI/RCA 405 line system so convincingly saw off the Baird system in the UK. (There were quite a few others, it has to be said!) And all through the analogue era it served very well - compared to a comparable analogue progressive system it gave about 0.7 the quality at half the bandwidth. The debate has really only been in the last ten years, and for the reasons above there were arguments on both sides. Ultimately I've never been in favour of interlace per se - but do think it was right to set the HD broadcast standard around the 1080 system rather than 720. And if that meant interlace for such as sport programming, so be it.

But it's now time to move on, and the future is indeed progressive.
 
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I think the Kell factor is true for scanning CRT systems but not sure that is the case for discrete pixel based systems with no scanning beam where the data comes from a CMOS sensor and is actually a matrix ( 1920x540 for each field ) to start with. Your same source indicates that for CCD/CMOS sensors and flat panel displays the Kell factor can be as high as 0.9. It is still subject though so one could be optimistic and say 1.0 especially for the oversampled sensors that are now used in cameras !!! The Sony 1" sensors are 20Mpixels oversampled to produce what in HD is a 2Mpixel image or 8Mpixels in UHD.

Interlace was great for its time and modern technology can display this very well. I agree though its time to move on to full progressive acquisition and in high frame rates too as I like the smooth motion. I hope I am still around to see 8K at 120fps or more. I want to shoot video that looks like I am still there when I watch it later.
 
Kalevi Qvick said:
Some suggestions for next firmware or do I miss something?

- focus assistant should be available also when rec is on. Or is it selectable in some where in menu? Now when I press "rec" the assistant disappears. I have seen pictures about demo cameras where there is red rectangle around the lcd during the focus assistant.
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The magnified focus assist is not available during recording, but the focus-in-red feature is. That is what causes the red rerectangle around the LCD.

low light mode can not be assigned to a user button. I suppose this should be used before the gain adjustment.
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the HIGH SENS mode is not assignable to a User Button. It is something you have to set in the System Mode menu.

- flash band protection should be also assignable to user button ?
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It already is.
 
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