>> *Not* having to tie things together is an asset. Let each phone/camera
>> act as an independent source and harvest the data after the shoot.
>
> Oh, they can do that, too, on battery power. Date/time is stamped
> on stills, I'm not sure about video files...
You need to have a timestamp per frame as the sorts of time stamps
that a DVR would likely apply are just intended for human consumption
(e.g., time-of-day... HH:MM:SS)
>> But, you need a way of *virtually* tying them together -- in time.
>> If I was looking to design such a solution, I'd rely on the timestamps
>> available from their GPS receivers...
>
> That timestamp is certainly part of the security-DVR solutions, and if
> you used a POE type camera/DVR solution, the wiring is not very troublesome...
But their still wired together. The beauty of an iPhone (or any
stand-alone digital camera) is that all you'd need to do is put
it in a support, point it (using its screen/viewfinder as a guide)
and press "record".
If you wanted to add another camera (e.g., to "watch" the audience's
reactions), just point one facing outward.
>>> One of my DVRs has four video but only two audio channels.
>
>> Yes. You'd collect the video/audio/time streams from each camera
>> and load them into the NLE, massaging the "composite" there.
>
> Yeah, thus the clap-stock used at scene inception in classic videography...
Yes. Note the electronic version now has a timecode displayed in LEDs.
If (see previous product postings) each camera embeds an SMPTE time code
in the video (audio), then *that* acts to tie their content together.
So, no need to ensure each camera is turned on at the same time, etc.
>> ...you can duck the audio from the camera watching the
>> palette -- UNTIL the brush comes into scene (at which point, hearing the
>> brush slop around the palette adds interest/realism to the presentation)
>
> Good point. It still seems to me that a central DVR with periperal
> cameras is going to be less of a herding-cats exercise. I'd expect that any
> iPhone solution will break with some future (or be incompatible with
> some past) IOS version.
My current solution relies heavily on "ancient" hardware -- simply
to leverage my prior knowledge.
My original goal was to "scrap three cameras" (4th quarter is my annual
equipment "re-visioning") in favor of something smaller, more convenient
to lug around (my cameras aren't particularly heavy but they are
incredibly bulky) while preserving that shoot capability.
Now, I'm becoming opportunistic: if I can come up with a solution
that lets me bow out of the actual shoots (it's typ a 4-5 hour
commitment on my part for an hour of presentation) so SWMBO can
set things up by herself, that's a big win! Still leaves me with
the post but at least that's an *interesting* activity...
Reply by whit3rd●October 24, 20212021-10-24
On Saturday, October 23, 2021 at 12:52:11 AM UTC-7, Don Y wrote:
> On 10/22/2021 11:51 PM, whit3rd wrote:
> > On Thursday, October 21, 2021 at 3:23:34 PM UTC-7, Don Y wrote:
> >> Can one synchronize the video streams from multiple iPhones?
> > There's myriads of old point-and-shoot
> > autofocus/autoexposure cameras with analog video outputs,
> > even some with HDMI, and you can just pipe as many as you want into
> > a security-type DVR (up to four inputs is cheap, eight or more is available).
> *Not* having to tie things together is an asset. Let each phone/camera
> act as an independent source and harvest the data after the shoot.
Oh, they can do that, too, on battery power. Date/time is stamped
on stills, I'm not sure about video files...
> But, you need a way of *virtually* tying them together -- in time.
> If I was looking to design such a solution, I'd rely on the timestamps
> available from their GPS receivers...
That timestamp is certainly part of the security-DVR solutions, and if
you used a POE type camera/DVR solution, the wiring is not very troublesome...
> > One of my DVRs has four video but only two audio channels.
> Yes. You'd collect the video/audio/time streams from each camera
> and load them into the NLE, massaging the "composite" there.
Yeah, thus the clap-stock used at scene inception in classic videography...
> ...you can duck the audio from the camera watching the
> palette -- UNTIL the brush comes into scene (at which point, hearing the
> brush slop around the palette adds interest/realism to the presentation)
Good point. It still seems to me that a central DVR with periperal
cameras is going to be less of a herding-cats exercise. I'd expect that any
iPhone solution will break with some future (or be incompatible with
some past) IOS version.
Reply by Don Y●October 23, 20212021-10-23
On 10/22/2021 11:51 PM, whit3rd wrote:
> On Thursday, October 21, 2021 at 3:23:34 PM UTC-7, Don Y wrote:
>> iPhones are purported to have kick ass cameras. But, do they
>> "play well with others"?
>
>> Can one synchronize the video streams from multiple iPhones? And,
>> add external mics? Pro cameras have a gazillion connectors for
>> all of these purposes but the iPhone has just the one (plus BT).
>
> It's also got WiFi...
Yes, but I suspect BT has more focus on latency issues (used for
audio) than the WiFi interface (which is typ used for bulk data)
> but why iPhones?
My interest was sparked from adverts touting the quality of
iPhone cameras. No doubt there are other digital cameras
with comparable quality but iPhones are ubiquitous.
They are also very small/lightweight. E.g., it is tedious to set up my
(ancient) cameras as they are large and relatively heavy (~10 lbs ea).
iPhones could be mounted on mic booms or selfie sticks attached
to tripods. I.e., *I* can possibly weasel out of having to attend
these events! :> (not likely when you have a car full of kit that
has to be uncrated, set up, cabled, etc.)
> There's myriads of old point-and-shoot
> autofocus/autoexposure cameras with analog video outputs,
> even some with HDMI, and you can just pipe as many as you want into
> a security-type DVR (up to four inputs is cheap, eight or more is available).
> And, they have a tripod-friendly mount.
*Not* having to tie things together is an asset. Let each phone/camera
act as an independent source and harvest the data after the shoot.
This isn't really practical for an iPhone by itself as the mic isn't
particularly directional, etc.
But, you need a way of *virtually* tying them together -- in time.
If I was looking to design such a solution, I'd rely on the timestamps
available from their GPS receivers -- which I assume is more precise
than the (phone) "network time" that they present to the user. Embed
this into the video stream "in some way" (ideally SMPTE time code
as it is "portable") where it is affixed to specific frames (and audio).
[You might also want to look at the specifics of your DVR; many reduce
the effective frame rate "per camera" as the number of cameras increases
(to keep disk bandwidth constant). Esp those that do scene analysis]
> Editing video clips together would be an offline operation, of course.
> One of my DVRs has four video but only two audio channels.
Yes. You'd collect the video/audio/time streams from each camera
and load them into the NLE, massaging the "composite" there. Being able
to treat the streams as independent/self-consistent entities makes this
easier. E.g., you can duck the audio from the camera watching the
palette -- UNTIL the brush comes into scene (at which point, hearing the
brush slop around the palette adds interest/realism to the presentation)
Another win of a more modern camera (over mine) is that you can take
advantage of the increased resolution to do digital effects in post
(zoom, pan, etc.) without losing much quality (compared to what my
cameras could do). E.g., take the palette PIP window and explode it
to full-screen when the attention shifts to that...
Reply by whit3rd●October 23, 20212021-10-23
On Thursday, October 21, 2021 at 3:23:34 PM UTC-7, Don Y wrote:
> iPhones are purported to have kick ass cameras. But, do they
> "play well with others"?
> Can one synchronize the video streams from multiple iPhones? And,
> add external mics? Pro cameras have a gazillion connectors for
> all of these purposes but the iPhone has just the one (plus BT).
It's also got WiFi... but why iPhones? There's myriads of old point-and-shoot
autofocus/autoexposure cameras with analog video outputs,
even some with HDMI, and you can just pipe as many as you want into
a security-type DVR (up to four inputs is cheap, eight or more is available).
And, they have a tripod-friendly mount.
Editing video clips together would be an offline operation, of course.
One of my DVRs has four video but only two audio channels.
Reply by Don Y●October 22, 20212021-10-22
On 10/22/2021 6:02 PM, ke...@kjwdesigns.com wrote:
> On Friday, 22 October 2021 at 12:38:28 UTC-7, Don Y wrote:
>> On 10/22/2021 2:53 AM, Clive Arthur wrote:
>>> On 21/10/2021 23:23, Don Y wrote:
>>>> iPhones are purported to have kick ass cameras. But, do they
>>>> "play well with others"?
> ....
>
> This app can synchronize multiple iPhones for taking multi-camera videos.
>
> https://www.engadget.com/2019-09-11-roland-ios-app-creates-multi-camera-videos-in-a-single-take.html
https://www.timecodesystems.com/ultrasync-blue-on-iphone/
can timestamp the videos on a cluster of phones so their video
can be synchronized in post (assuming you retrieve the individual
videos from each phone at some later time AFTER the shoot)
I don't see a mechanism for genlocking, though.
Reply by ke.....@kjwdesigns.com●October 22, 20212021-10-22
On Friday, 22 October 2021 at 12:38:28 UTC-7, Don Y wrote:
> On 10/22/2021 2:53 AM, Clive Arthur wrote:
> > On 21/10/2021 23:23, Don Y wrote:
> >> iPhones are purported to have kick ass cameras. But, do they
> >> "play well with others"?
> On 21/10/2021 23:23, Don Y wrote:
>> iPhones are purported to have kick ass cameras. But, do they
>> "play well with others"?
>
> I know nothing of iPhones,
Nor I! :>
> but with an appropriate app, Android phones can be
> used as 'IP cameras' which allow live video view over WiFi. Don't know how good
> the sync is.
>
> I've used Windows phones for this, but in different rooms and no need for sync.
> These phones are dead now.
In theory, a phone *could* inject an SMTPE timestamp into the video stream
sourced from the GPS timebase. But, I've no idea if there are any *real*
guarantees as to latency/jitter between the actual received time signal
and the signal available at the application layer. Presumably, two
phones would be able to lock to relatively tight precision (note that
you also have to sync audio so the tolerances there are tighter).
I.e., instead of genlocking the cameras, let them each *report* their
apparent timestamps and handle synchronization in post.
I saw the tail end of a TV ad that showed an iPhone in some sort
of holder/frame to make it more presentable as a "pro" camera (I am
assuming it wasn't just a prop). No doubt, pitching the quality of their
video. But, conveniently ignoring all of the other issues involved in
a shoot! (how do you route the video to a "monitor" so someone other
than the cameraman can actually SEE what you are shooting?!)
And, using quality microphones (instead of the dinky mic in the camera).
And the inability to genlock.
etc.
Apparently, there's at least one product that purports to address the
timecode issue. So, I sent out a request to friends/colleagues for
"old iphones" in order to see how that works. And, what *other* devices
I'll have to acquire for a COMPLETE solution.
[There's a reason to NOT upgrade kit -- you don't have to go through
all these gyrations to find an *equivalent* solution to the one you
already *have*! :< ]
Reply by Clive Arthur●October 22, 20212021-10-22
On 21/10/2021 23:23, Don Y wrote:
> iPhones are purported to have kick ass cameras. But, do they
> "play well with others"?
>
> --- To Coda (TL;DR)
<snip>
I know nothing of iPhones, but with an appropriate app, Android phones
can be used as 'IP cameras' which allow live video view over WiFi.
Don't know how good the sync is.
I've used Windows phones for this, but in different rooms and no need
for sync. These phones are dead now.
--
Cheers
Clive
Reply by Don Y●October 21, 20212021-10-21
iPhones are purported to have kick ass cameras. But, do they
"play well with others"?
--- To Coda (TL;DR)
Some years ago (20?) I purchased some DV cameras for a project,
similar to this:
<http://pro.jvc.com/prof/attributes/tech_desc.jsp?model_id=MDL101367&feature_id=02>
Of course, when project was done, they just got stored (never discard
something that you may need at a later date for a yet-to-be-conceived
purpose!).
[Tech is old but video quality is still good enough for purpose described
below -- and, I already have all of the tools to use things as needed!]
When SWMBO started actively "painting" (think artsy-fartsy), I was
asked by some of her friends to record some of their presentations/demos
and transfer to DVD. I typically set up one camera to capture the
artist from the "audience's" PoV. Another pointed straight down to
image his canvas. And, a third pointed into his pallette (so folks
can see which pigments he's mixing to make the color that he'll be
applying, presently).
And, I can stay the hell out of the scene as I can control the
cameras remotely.
In post, I can piece together the three video streams as multiple PIP
*CONCURRENT* video scenes on the same screen. Audio and three video
streams all synchronized (within a frame).
But, this is tedious to lug all the kit to the shoot. Each camera
is stored in a travel (shipping) box that's ~15x23x34". Plus, tripods,
mics, cables, etc. The three camera cases fill the back seat of my
car with the other cruft tossed in the trunk.
So, that leaves space for just three "occupants" in the vehicle:
Me, SWMBO and a (blind) friend of hers for whom she often provides
transport. But, that's in *my* vehicle! In SWMBO's vehicle, there's
no room for the friend as the front seat has a "center console" that
eats up a seating position.
It would be REALLY nice to be able to use three iPhones in place of
these three beasts. And, scrap these cameras (though save the shipping
containers -- which means no real SPACE savings!)
--- Coda
Can one synchronize the video streams from multiple iPhones? And,
add external mics? Pro cameras have a gazillion connectors for
all of these purposes but the iPhone has just the one (plus BT).
In the past, I've tried "manually" synchronizing the video
streams from three separate cameras in the NLE. The results are
disappointing (and it is time consuming -- esp if you stop/start
cameras during the filming!)
It seems like folks just use the iPhone as a single, standalone
camera (still/movie) and not in a more professional environment.
Google didn't turn up any hits for the terms I tried...