Silicon Imaging SI-2K MINI camera

[Andrew Huebscher]

Hello,

 

I'm shooting a western in L.A. next month, and we will be using Silicon Imaging's SI-2K MINI recording system tethered to a laptop. For those not familiar with the camera, it's a CMOS based 2/3" imager in a small box about 3.5" x 3.5" x 2.5" small. It will have a B4 or PL mount on the front, and a base plate for which to attach accessories. You can read about this system at www.siliconimaging.com/DigitalCinema/

 

The challenge with the camera is that it has to be tethered via ethernet to a computer on set (they are making an all-in-one "camcorder" version, but it won't be ready in time for our shoot). The director would like to make extensive use of Steadicam, and having never used this camera in that way, I'm looking for suggestions/experience on working with a tethered system and a small camera head.

 

Here are some other challenges/notes:

 

-No composite or HD video out. The output has to come out of a laptop. My MacBook Pro has a DVI port, so my thinking is I could use a DVI-VGA adapter, then a VGA-Composite video adapter and send a BNC feed back taped to the GigE cable to go into the operator's monitor.

 

-Fully compatible with Anton Bauer Gold-Mount battery system (14.4V Nominal). The MINI has an AB mount on the base plate, with a D-tap for accessories.

 

-How to do Steadi 360º+ moves when tethered?!

 

 

Thanks in advance,

 

Andrew Huebscher

DP - Los Angeles

 

Disclaimer: I do not, and have never worked for Silicon Imaging, Inc.

[Dan Coplan]

First idea that comes to mind is using a weight cage. Mount the camera inside the cage and the laptop on top. I would think it'd be best to close the top of the laptop as much as possible to keep the height down both for stability and to avoid it acting like a sail. Then it's as if you're not tethered and you've got manageable weight.

 

Take a pic and post when you get it figured out. I've thought about this setup before so I'm curious how it actually ends up working out.

 

Dan

[Lukas Franz]

Andrew,

 

I never worked with this camera, but I'm actually a well educated video tech. So, my thoughts about it:

 

To use passive adapters I think wouldn't really work. For a DVI to VGA the DVI needs analog connections, but would probably work. A VGA to composite doesn't exist as a regular adapter, maybe an active converter helps, 'cause VGA is not a video signal like composite or Y/C.

 

My idea: if you connect the camera over ethernet to a laptop, wouldn't it be possible to connect it to any computer with an ethernet board and required software!? What if you take a MAC Mini and put it onto your rig. Record it directly to the MAC Mini and remote it through a wireless connection of keyboard, mouse and monitor. Power shouldn't be a problem, I think. ???

 

If you need to have the recorder (laptop) separated from your camera, that means my idea above doesn't work, use the ethernet cable (it's possible to do shots that way, ask some tv working pals. And get a good assistant.) and try to convert the computer output to a standard video signal and send it back to your operating monitor wireless or thru a cable, as you mentioned. The big problem here is: you get a delay by the reason of converting and sending the signal to and fro. I guess, it wouldn't be possible to operate that way, would it?

 

But everything is just theoretical. I think, you need to try out the different possiblities. Or maybe someone else on the forum has another idea!?

 

Good luck.

Lukas

 

Oh, and about the size of the camera. Use a cage and weight plates, like you do with smaller video cams.

[Dan Coplan]

Here's a wacky idea. If you use a laptop, use the laptop screen as your monitor. Gut feeling tells me this wouldn't work as well as it sounds, but you never know. Would certainly be different and interesting to try.

 

Dan

[Tom Wills]

Ethernet cables are big, nasty, thick cables. See if you can get a short ethernet cable, put a coupler on the vest, and strip all the insulation off the short cable. Then, it'll just be 4 twisted pairs of very thin wire. It won't be pretty, but it might lighten up the cable a bit. And, I'm sure somebody else can come up with a better solution than this, but if push comes to shove, a tiny little security camera placed conveniently above or below the SI and adjusted to be framing "pretty close" to the SI might do the job for monitoring, though certainly a proper solution would provide better results.

[Andrew Huebscher]

First idea that comes to mind is using a weight cage. Mount the camera inside the cage and the laptop on top. I would think it'd be best to close the top of the laptop as much as possible to keep the height down both for stability and to avoid it acting like a sail. Then it's as if you're not tethered and you've got manageable weight.

 

The camera becomes a little heavier once fitted with the base plate, rods, rem FF, MB, and battery. Not sure about mounting a laptop on top. Is there a way for a SC op to wear a backpack? The camera doesn't have an EVF yet, so most users have a 7" touchscreen VGA LCD. They claim it does well in daylight, but most Steadi ops I know would still probably prefer their own display. But it may be possible to rig this display on top of the built in one.

 

 

To use passive adapters I think wouldn't really work. For a DVI to VGA the DVI needs analog connections, but would probably work. A VGA to composite doesn't exist as a regular adapter, maybe an active converter helps, 'cause VGA is not a video signal like composite or Y/C.

 

I added a step. With this adapter, it looks like I could go directly from the DVI port out to a S-video/composite display.

 

http://store.apple.com/1-800-MY-APPLE/WebO...rnMore=M9267G/A

 

 

What if you take a MAC Mini and put it onto your rig. Record it directly to the MAC Mini and remote it through a wireless connection of keyboard, mouse and monitor. Power shouldn't be a problem, I think. ???

 

I like your thinking. Unfortunatley, the computer has to conform to very specific specs: Intel Core 2 Duo 2.4GHz or faster, ethernet adapter that supports jumbo packets, and a beefy graphics card. The Mac Mini doesn't have anything above 2.0 (yet).

 

The big problem here is: you get a delay by the reason of converting and sending the signal to and fro. I guess, it wouldn't be possible to operate that way, would it?

 

That's a very good point. I will test this to see if there is a delay. As a DP/op, I know even the slightest delay could be unacceptable.

 

Here's a wacky idea. If you use a laptop, use the laptop screen as your monitor. Gut feeling tells me this wouldn't work as well as it sounds, but you never know. Would certainly be different and interesting to try.

I think a 15" notebook would be kinda unwieldly, especially as their screens tend to not do well in direct sun.

 

Ethernet cables are big, nasty, thick cables. See if you can get a short ethernet cable, put a coupler on the vest, and strip all the insulation off the short cable. Then, it'll just be 4 twisted pairs of very thin wire. It won't be pretty, but it might lighten up the cable a bit. And, I'm sure somebody else can come up with a better solution than this, but if push comes to shove, a tiny little security camera placed conveniently above or below the SI and adjusted to be framing "pretty close" to the SI might do the job for monitoring, though certainly a proper solution would provide better results.

 

Kinda makes me think back to having a backpack with the computer inside. Another thing to consider, however, is the director will want to watch the take as it's happening. If I could get a laptop mounted to a Steadicam op (maybe on their back, their bum, their head -- whatever), I could convert that DVI to composite video (if there's no delay), and then that signal gets sent to the op's display and via RF (i.e., Modulus) to video village.

 

I need Doc Brown for this one....

 

 

Andrew Huebscher

DP - Los Angeles

[RobVanGelder]

Having some experience with conversions to different signals in video, i can assure you that you will find a delay between input and DVI output of around 6 frames, but probably much higher as you need at the end a signal that is scaled down to say 640/480 pixels, as that is what most small screens (7 or 8") can handle. So in fact you have to conversions, the first RAW data to 2K (HD) and then to a smaller size for your screen and then to VGA/analog composite.

 

Just a guess, but I would be very surprised if you get under 12 frames delay in total, going this route, even with the fastest laptop.

 

Having said that, you might opt to use the laptop's screen as your steadicam monitor, or detach the screen from the other electronics.........

 

This is a fun project, I wish i could be involved!

 

 

Please let us know.

[Lukas Franz]

I added a step. With this adapter, it looks like I could go directly from the DVI port out to a S-video/composite display.

 

http://store.apple.com/1-800-MY-APPLE/WebO...rnMore=M9267G/A

 

Ok, this is a specific adapter for Mac I actually didn't know. It seems to tell the graphic card to scale and convert the output signal to video and send it thru the DVI connector. This only works with Mac and special ATI card.

 

Doesn't there exist any small monitor video DVI input? Or you may use components thru DVI-VGA-components analog adapter. I'm shure there are HD monitors with RGBHV inputs. And particularly it has no delay :-)

 

Cheers. Lukas

[Dan Coplan]

Just read about the Doremi DVI to high def and standard def SDI video converter, the DSDI-20.

 

Don't know anything about it, just saw a blurb in a magazine.

 

Dan

[Lukas Franz]

Dan,

 

here's a link to the converter: http://www.doremilabs.com/products/DSDI-20.html

 

It looks pretty interesting. But a handicap could be the powering with 5 Volts.

 

Cheers, Lukas

[Mark Karavite]

Regarding the Doremi converter, I don't think the big issue would be feeding it 5v power. An MK-V Nexus base has an adjustable recorder power output, and 5v is selectable. For other sleds, Jim Bartell can make you a cable that converts 12v output to 5v. He has been making these for Archos recorders (along with Fred Davis of PCS).

 

I think the bigger issue with this converter is that it only outputs SDI. Most Steadicam monitors are NTSC, and even though they are both standard def signals, they are not the same. Neither my greenscreen or LCD are SDI compatible, only NTSC. Don't get caught on that!

 

My first call would be to the camera's manufacturer. They will want their camera to work well in this production environment, and they have more resources to make any modifications that might be needed. I'd sollicite their help on this one, it's in both your interests.

 

Good luck,

Mark

[Gus Trivino]

Hi guys,

 

Im shooting in 10 days 1 week with the same camera.

Yesterday I went to see it working on a set, and I saw that I won´t have any video signal for my monitor... :ph34r:

If someone tried with an adaptor and it worked, please send me an email or please post the info.

Definitly, is not my favourite camera...

Best to all,

 

 

Gus