Forums > Jitter

Long firewire cable and iSight for shadow

July 14, 2006 | 3:23 am

Hi all,

I’m putting on a gallery installation that requires a webcam (an iSight) to be ceiling mounted — and just realizes that it means I’ll most likely need a very long firewire cable, perhaps 10m/30ft or so. Has anyone had experience with this?

The webcam will be analyzing projected video plus people’s shadows… I’m hoping that mounting it on the ceiling will allow it to miss people’s actual bodies and only see the shadows… if anyone has any thoughts about how I’m accomplishing that, they’d be welcome too. The patch is working well… now it’s just a matter of getting the right information to it!

Thanks,
Betsey


July 14, 2006 | 4:22 am

hi betsy! how’ve you been?

the spec for firewire says that the cable cannot be more than 4.5m
without a repeater box.

also, i have never gotten more than 15 unique frames per second out
of my isight even though it reports ’30 fps’. you can test this with
the jit.change object (or v.change if you are using softvns). you
might consider other webcams that may be cheaper and will give you
30fps like the fire-i form unibrain.

or you might consider using an analogue video camera source with a a
video capture device like the Alchemy card from Miglia or the
DFG-1394 from the Imaging Source. this would make the cable length a
non-issue.

hope it goes well :)

all my best,
jonathan

On Jul 13, 2006, at 11:24 PM, Betsey Biggs wrote:

>
> Hi all,
>
> I’m putting on a gallery installation that requires a webcam (an
> iSight) to be ceiling mounted — and just realizes that it means
> I’ll most likely need a very long firewire cable, perhaps 10m/30ft
> or so. Has anyone had experience with this?
>
> The webcam will be analyzing projected video plus people’s
> shadows… I’m hoping that mounting it on the ceiling will allow it
> to miss people’s actual bodies and only see the shadows… if
> anyone has any thoughts about how I’m accomplishing that, they’d be
> welcome too. The patch is working well… now it’s just a matter of
> getting the right information to it!
>
> Thanks,
> Betsey


July 14, 2006 | 7:11 am

1394store sell 10m cables and repeaters (if u need), cheap. check their fw
cams if you need wider lens for your installation.
does the isight allow different switching lens?

http://www.1394store.com/eshop/dept.asp?dept%5Fid=6

2006/7/14, jonathan marcus :
>
> hi betsy! how’ve you been?
>
> the spec for firewire says that the cable cannot be more than 4.5m
> without a repeater box.
>
> also, i have never gotten more than 15 unique frames per second out
> of my isight even though it reports ’30 fps’. you can test this with
> the jit.change object (or v.change if you are using softvns). you
> might consider other webcams that may be cheaper and will give you
> 30fps like the fire-i form unibrain.
>
> or you might consider using an analogue video camera source with a a
> video capture device like the Alchemy card from Miglia or the
> DFG-1394 from the Imaging Source. this would make the cable length a
> non-issue.
>
> hope it goes well :)
>
> all my best,
> jonathan
>
>
>
> On Jul 13, 2006, at 11:24 PM, Betsey Biggs wrote:
>
> >
> > Hi all,
> >
> > I’m putting on a gallery installation that requires a webcam (an
> > iSight) to be ceiling mounted — and just realizes that it means
> > I’ll most likely need a very long firewire cable, perhaps 10m/30ft
> > or so. Has anyone had experience with this?
> >
> > The webcam will be analyzing projected video plus people’s
> > shadows… I’m hoping that mounting it on the ceiling will allow it
> > to miss people’s actual bodies and only see the shadows… if
> > anyone has any thoughts about how I’m accomplishing that, they’d be
> > welcome too. The patch is working well… now it’s just a matter of
> > getting the right information to it!
> >
> > Thanks,
> > Betsey
>
>


August 6, 2006 | 10:53 pm

hey there

I found that the 10m firewire from unibrain didn’t work well – the Granite Digital was MUCH more reliable – but more $

best
jamie


August 31, 2006 | 5:56 am

better then never.
i just want to add, the unibrain cable costs 30 bucks, i used two of their
cameras in an outdoor (summer,Israel) installation, it still works, for two
months now, flawlessly.
i find Firewire convenient and clean looking, i daisy chained the two
cameras and the FW supplies 5v and grabs the video. with one wire running
back to the computer.
my only grips with the camera is that their sdk (which pointgrey gives for
free) is 590$, and that their sensor doesn’t offer *Partial Image Modes.*

2006/8/7, jamie jewett :
>
>
> hey there
>
> I found that the 10m firewire from unibrain didn’t work well – the
> Granite Digital was MUCH more reliable – but more $
>
> best
> jamie
>


August 31, 2006 | 7:44 am

I just bought a 10m firewire cable from pccables.com for $30. It
works just fine with my camera from imaging source. I’ve also had
unibrain cameras work with 10m cables. I’m guessing that the isight
should work as well over these cables.

wes

On 8/30/06, yair reshef wrote:
>
> better then never.
> i just want to add, the unibrain cable costs 30 bucks, i used two of their
> cameras in an outdoor (summer,Israel) installation, it still works, for two
> months now, flawlessly.
> i find Firewire convenient and clean looking, i daisy chained the two
> cameras and the FW supplies 5v and grabs the video. with one wire running
> back to the computer.
> my only grips with the camera is that their sdk (which pointgrey gives for
> free) is 590$, and that their sensor doesn’t offer Partial Image Modes.
> 2006/8/7, jamie jewett :
> >
> > hey there
> >
> > I found that the 10m firewire from unibrain didn’t work well – the
> Granite Digital was MUCH more reliable – but more $
> >
> > best
> > jamie
> >
>
>
>
>
>


September 13, 2006 | 9:20 pm

Thank you everyone,

I ended up not needing the long firewire cables after all, but all of this information is extremely useful. It’s good to know that they can work as I’m likely to need it again at some point.

Thanks!


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