jlauer
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Length of camera cable

Sat Feb 09, 2013 6:38 am

I'm wondering how long the camera cable can run? I've read a lot of the posts and it seems there's no real answer on how long the cable can run. I know the camera is kicking out a lot of data at 1080p and that the signal can degrade quite quickly.

I am building an open hardware laser with a Raspberry Pi as a centerpiece component. I want the camera module to be at the head end of the fiber laser which is about 1 meter in length from the Raspberry Pi. The camera module will be focused on the laser hitting whatever you're lasing such as cutting plastics, woods, laser soldering, etc.

So, can I have it a full meter away? If not, can I build an amplifier for the signal? I'd hate to have to put a Raspberry Pi right at the head end of the laser because that would be way too bulky and ruin the whole design. I could design an amplifier circuit that could perhaps be half way along the length, but even that is not ideal. Anyone have any ideas?

jamesh
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Re: Length of camera cable

Sat Feb 09, 2013 9:04 am

A meter is likely too far. We've used 15cm, and we think that's probably close to the maximum before the signal degrades. But you could just try it!
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Jim JKla
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Re: Length of camera cable

Sat Feb 09, 2013 9:15 am

The kit is so new it has to be at the trial and error stage
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rew
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Re: Length of camera cable

Thu Feb 21, 2013 10:00 am

My guess is that you can go much further than the experts predict.

Some cleverness and hacking may be required....

To prevent signal degradation, a solid powerplane has to be close by. Wrap an aluminium foil shielding around the cable and ground it well at one or both sides (I'm not yet sure what will work best: testing required).

To prevent power-degradation, place a capacitor on the power for the camera near the camera. Consider a thicker cable than the one in the flatcable.

I'm guessing a meter will be possible of you consider these tricks. Maybe even 5 or 10m!

A showstopper would be if the drivers at one end are so weak that any signal "sag" will prevent the other side from detecting the signal correctly. You will have an attenuation in the signals. But usually a small attenuation is acceptable, as long as the waveforms are preserved. That's what the aluminium foil shielding is for. It will make the signal cables into transmission lines which just attenuate the signals, but not distort them.
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psergiu
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Re: Length of camera cable

Thu May 16, 2013 1:57 pm

Now that the RPi Cameras have started shipping, has anyone replaced the standard Flex cable with a shorter or longer one ?

If yes - what flex cable you used and from where you bought it ?

jamesh
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Re: Length of camera cable

Thu May 16, 2013 2:13 pm

rew wrote: I'm guessing a meter will be possible of you consider these tricks. Maybe even 5 or 10m!
I think that prediction may come back and haunt you...
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cabe
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Re: Length of camera cable

Thu May 16, 2013 3:27 pm

As I was out of the country, I managed to miss the CPC order frenzy (soon gadget, soon.....)

Is it a standard n-pin ribbon cable? I think a short 75mm cable would be better suited to sticking to the front of a case without too much excess getting in the way.

PiFanatic
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Re: Length of camera cable

Sun Nov 03, 2013 7:21 pm

There are a few sellers on eBay offering these in different lengths, for example: http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... RK:MESE:IT - Check prices as they vary from seller to seller.

wibble82
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Re: Length of camera cable

Mon Nov 04, 2013 9:57 am

If you try this could you post your results - I'm building a robot and am currently deliberating whether I need to place the pi's in the head next to each eye, or whether I can take the camera cables down to the chassis. Would love to hear your results.

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jbeale
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Re: Length of camera cable

Wed Nov 06, 2013 4:50 am

I have tried the BitWizard ribbon cable adaptor on a R-Pi camera module, with a combined cable length of 4 meters (13 feet) and it works OK. I would not worry much about any reasonable length of cable*. See also: http://www.raspberrypi.org/phpBB3/viewt ... 59&t=48330 and http://www.raspberrypi.org/phpBB3/viewt ... 84#p427987

* unless you are making a product for sale and have to pass a radiated-emissions test for FCC or CE mark.

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