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Re:Approved Cameras by kaczordon on Saturday January 08, 2022 @07:21PM (#29858284)
> Also it looks like 4K is their minimum standard now. I bet the higher resolution makes it easier, with big*ss GPUs to clean up the raw footage.

Resolution is far less important than bit color depth. We barely need 4K(Alexa used to be 2K) much less 8K footage for something to look good on a tv.

Re:Approved Cameras by rectang on Saturday January 08, 2022 @07:30PM (#29858367)
I would think that capturing at higher resolutions makes it feasible to crop and zoom? In digital production, you always want to work at high resolution for all intermediate stages, then reduce bit depth only during the final output stage.

When I worked in music production a while back, we often had the problem of source material recorded at low amplitude to 16-bit media (e.g. DAT, CDDA, ADAT). While 16-bit is theoretically sufficient, in the real world you need headroom while recording in order to avoid clipping. So we'd often wind up with grungy sound from inadequate bit-depth during capture and intermediate production.

Re:Approved Cameras by ace2358 on Saturday January 08, 2022 @07:43PM (#29858470)
I know recording live music can get hairy, but yikes! How was 16bits not enough? Were all the preamps set to max? Who records at -12db - -6db? Record at a way lower level and boost at the amp stage?
Re:Approved Cameras by rectang on Saturday January 08, 2022 @08:03PM (#29858618)
Imagine you're recording highly dynamic music, like Jazz. Clipping is absolutely never OK. You have to leave tons of headroom, there's no other way. So 16 bits is not enough for live capture — especially when the source is dynamic or the recording conditions are chaotic.

The studio I used to work at was one of the first ADAT studios back in the 90s, and they did a lot of rock. One of the ways they got past the limitations of the medium was to compress and limit to tape. You generally don't want to do that unless you have tons of time to set up and get it right (a la Rudy Van Gelder), which was not in most budgets. But it worked well enough and the ADAT recordings out of this studio sounded way better than most.

Mercifully storage has gotten cheaper in the decades since and you really shouldn't capture to 16 bits any more.

Re:Approved Cameras by tshaddox on Sunday January 09, 2022 @12:28AM (#29860467)
How much post-production dynamic range do you really need/want for live jazz recordings? Surely 50 dB would be plenty, and even that would be pretty impractical to listen to except in very quiet environments. Wouldn’t 16 bit digital audio easily give you 50 dB of usable dynamic range and still have like another 50 dB of headroom?
Re:Approved Cameras by Taek on Sunday January 09, 2022 @06:42AM (#29862425)
You need 8 bits to do 48dB, so if you want your music to have 96dB of dynamic range and you want your editor to be able to slide things around 48dB without perceptible loss of quality, you need to record at 24 bits of depth.

If you record at 16 bits of depth you are pretty much automatically forcing your engineer to choose between quality and range when they are normalizing the recording.

Re:Approved Cameras by tshaddox on Sunday January 09, 2022 @01:00PM (#29865704)
Listening to music with 96 dB of dynamic range is extreme though, right?
Re:Approved Cameras by rectang on Sunday January 09, 2022 @01:29PM (#29865969)
You seem quite determined to leave inadequate margin for error. :(

The most important rule of audio recording is "always be ready to roll tape". What the engineer does is of little consequence compared to the talent. Don't ever fuck up a keeper take.

Recording with some extra bits means that even if your gain staging was bad, you just get some extra uncorrelated noise, not correlated quantization distortion.

As for whether this stuff is perceptible, there are two issues at play. First, differences which are not perceptible during production can result in a perceptible difference in the final product. This is easiest to understand with a visual analogy: if you have inadequate resolution of an image during processing, the end result may be slightly defocused and smeared.

Second, as I described elsethread, quantization distortion is a particularly pernicious form of degradation, poisonous in small amounts. https://www.youtube.com/watch?v=8KkS4NSv-0M It is hard to listen for it during production, so we defend against it by giving ourselves lots and lots of headroom.

Re:Approved Cameras by tshaddox on Sunday January 09, 2022 @03:23PM (#29866965)
I get it. I’m asking what dynamic range you need for the completed production, and how much additional headroom you need when recording. I don’t think you normally would need 96 dB for the completed production, because that would be very impractical to listen to.
Re:Approved Cameras by rectang on Sunday January 09, 2022 @06:13PM (#29868436)
16 bit certainly suffices as a delivery format. Many listening environments provide far less dynamic range (e.g. cars) and environments where the lowest level details aren't buried in the ambient noise floor are going to be few and far between. Even though it is possible to encode information below the noise floor in practice information that far down isn't going to be perceptible. (A practical definition of "perceptible" might be "able to be distinguished in an ABX test by a trained listener".)

As for how much safety margin is "enough" during initial capture... We're looking at a stark choice between either 2 or 3 bytes per sample. 2 bytes seems to be borderline, while 3 bytes seems to be plenty. It would be hard to quantify a safety margin more precisely than that.

Re:Approved Cameras by rectang on Sunday January 09, 2022 @02:40AM (#29861169)
Say that I need a 300x400 image for a webpage. Does it make sense to set my camera to take 300x400 pictures? What happens when we crop and postprocess?

If we want the best quality end product, free from low-res artifacting, we need to preserve an excess of resolution all the way through production until the final export. Exactly how headroom much is enough? Enough that artifacts arising from insufficient resolution are not perceivable in the end product.

Re:Approved Cameras by tshaddox on Sunday January 09, 2022 @02:53AM (#29861250)
Yes, I understand the reasons to have enough dynamic range and enough headroom. My question is about what specifically is enough.
Re:Approved Cameras by blep-arsh on Sunday January 09, 2022 @03:47AM (#29861551)
I think 16-bit quantization noise level is usually lower than the noise of all the analog hardware before the ADC, but 24-bit quantization noise seems to be lower than even the internal noise of audio ADCs so there seems to be no reason to go higher.
Re:Approved Cameras by m-ee on Saturday January 08, 2022 @11:08PM (#29859979)
I had the privilege of visiting the van Gelder studio in high school. I asked him about analog vs digital and surprisingly he said he was all in on digital and spending his days remastering his old work with modern tools.
Re:Approved Cameras by eyelidlessness on Saturday January 08, 2022 @09:04PM (#29859084)
My understanding is that 24-bit source material (the standard when I was last recording which was several years ago) provides enough dynamic range that you can bring up the desired volume without overly muddying quiet sections with noise, especially when mixing multiple sources where that noise adds up quickly. My own personal experience recording at 16 bits was… “I must play louder and overstate my song’s understatements” because I never could get a 16 bit output that didn’t sound like garbage. Granted I’ve never been more than a novice at recording and I’m certain there’s more I could learn to work with the lower bit rate but… why?
Re:Approved Cameras by eyelidlessness on Saturday January 08, 2022 @09:10PM (#29859141)
Also: this got me wondering about how much the “loudness wars” and “brick wall” music products overlap (in time) with the almost total transition to digital recording. It also got me wondering how much the more gradual digital transition affected musical style and taste. If analog recording captured a much more flexible dynamic range, it’s easy to imagine a lot of other recording artists similarly deciding “fuck it play it louder”. And it’s easy to imagine that culturally influencing louder recording targets generally.
Re:Approved Cameras by rectang on Saturday January 08, 2022 @09:54PM (#29859489)
The resolution bottlenecks of early digital as described in this thread are not related to the loudness wars of the aughts. If you were doing big budget recordings back then you were either doing 2" analog or you had enough setup time to set gain levels carefully and "fill up the meters" for your digital recorder.

Recording close-mic'd drums to analog tape is actually a useful technique when maxing out levels because analog tape saturation can be aesthetically superior to digital peak limiting for shaving drum peaks — analog tape saturates high frequencies first. It wasn't uncommon to either record basic tracks to analog then transfer to Pro Tools, or even to track to Pro Tools then bounce the drums out to analog tape and back.

For the record, there were loudness wars back in the vinyl days, since it was seen as important to have your 45 rpm single "compete" with others in the jukebox. It wasn't something new in the aughts.

> If analog recording captured a much more flexible dynamic range

It doesn't, especially not in comparison to modern digital. Dynamic range is not a strong point of analog because of tape hiss.

The issue with low res digital is that truncation distortion is non-harmonic (not an integer multiple of the input frequency) and so is disproportionately aesthetically damaging even in small quantities — in other words, digital grunge sounds worse than tape hiss.

Re:Approved Cameras by ZiiS on Sunday January 09, 2022 @04:08AM (#29861671)
It is trivial for modern hardware to work at 24bit. 16bit hardware is probably old, overly value engineered, or deliberatly operating below its capacity. These are all more plausable reasons for it to sound bad.
Re:Approved Cameras by rbanffy on Saturday January 08, 2022 @07:54PM (#29858541)
> capturing at higher resolutions makes it feasible to crop and zoom?

The more you capture, the more you have to play with at later production stages.

Re:Approved Cameras by germinalphrase on Saturday January 08, 2022 @07:58PM (#29858570)
And pay for. Larger data size across the chain isn’t costless.
Re:Approved Cameras by rbanffy on Sunday January 09, 2022 @03:43PM (#29867135)
Overall, data storage is not a large fraction of the cost of a TV series or movie production. If your assets grow too big and you don't plan on accessing them, you can store them in cold cloud, or archive-grade BD and tapes.
Re:Approved Cameras by Pulcinella on Saturday January 08, 2022 @09:10PM (#29859138)
I wish we would move to higher bit color for playback as well. Dark scenes very easily result in banding (especially with streaming compression). With video shot with cameras there is usually noise and grain (real or artificial) to help break it up some, but dark scenes in video games almost always look like garbage to me. Some games, like Playdead’s Inside get around this by, again, add a ton of noise to the image, but that doesn’t always work stylistically.
Re:Approved Cameras by ollifi on Sunday January 09, 2022 @05:10AM (#29861976)
Also compression. ARRI 2.5k cameras made decent images as they were lot less compressed as some 4K cameras at the time.

Netflix streams 4K but often doesn’t look so great over internet compared to any cinema in my area which projects only 2K on a huge screen but from bigger files.

Re:Approved Cameras by WalterBright on Saturday January 08, 2022 @08:35PM (#29858869)
> Resolution is far less important than bit color depth.

I discovered this playing with my scanner, looking for the best settings. It surprised me.

Re:Approved Cameras by shiftpgdn on Saturday January 08, 2022 @07:27PM (#29858340)
Sure is nice to crop in though.
Re:Approved Cameras by nopenopenopeno on Sunday January 09, 2022 @02:21AM (#29861059)
If you’re shooting 4K, you have to be calculated with your lens configuration to actually get that resolution at the sensor. After that kind of effort, cropping your shot in post is going to be a silly step to take.
Re:Approved Cameras by shiftpgdn on Sunday January 09, 2022 @08:44PM (#29869577)
You don’t have to crop in significantly, but just trim edges/etc.