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It appears the Raspberry Pi camera module v2 includes a 15cm ribbon cable, to connect it to the Pi. But I would like to have the camera sited further from the Pi, maybe a few metres away.

So can this cable be extended, or replaced with a longer cable? What sort of cable is required, and where can I get one? Is there any limit on the maximum cable length that will work?

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    Yes, I've used it successfully with a 24-inch cable. Adafruit sells them in various lengths, but you should really use the shortest one that will do the job, as they are fragile and you don't want them accidentally kinked.
    – JayEye
    May 7, 2016 at 23:11

5 Answers 5

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The length limits come from two requirements: signal quality, and signal delays. A 1m cable will introduce about 5ns of delay (speed of light in circuits is a lower than in vacuum!), so if you are running at 1GHz, there are five symbols in transit on that 1m cable. It this particular case it probably does not matter (it's more important that the signal paths are of exactly the same length), but this is the sort of consideration that most people won't think about.

The standard (at least what's open to the public: http://mipi.org/specifications/physical-layer) only mentions length considerations for M-PHY ("Distance: optimized for short interconnect (<10 cm) but extendable to a meter with good quality interconnect or even further with optical converters and optical waveguides"); D-PHY is a lot simpler, so it should have no problem with longer lengths as far as signal delays are concerned.

As @joan said, a long cable makes you more susceptible to interference from others. It also makes you more likely to interfere with other equipment, your neighbor's old analog TV, or maybe another pi on the next shelf with equally long cables. Hence my original admonition of keeping things as short and as straight as possible.

If you are thinking of shielding the flat cable with aluminum foil, you may or may not get a working cable: you will be adding a lot of capacitance, changing the transmission line characteristics.

I realize this is probably more detail than you needed, but someone may find it useful in the future :)

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  • Just a minor correction about the statement "speed of light in circuits is a lower than in vacuum". I assume it is obvious you too, and it was only a minor faulty reasoning, but there is no light transmitted in the wire (that is no glass fiber), neither have we vacuum typically in the room. That is the speed of the electrical signal transfered in the wire about the ligth detected by the camera. This signal is delayed in this case, when we have a longer cable. Without knowing the exact use case (face recognition?) where the long cable is required, it is hard to say if delay a problem is.
    – pholpar
    Jan 4, 2022 at 10:32
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Today I was able to use a 2m cable with a PiCam v2.1, after first verifying everything was working with the very small cable provided with the camera.

This is the long cable that worked for me:

Adafruit Flex Cable for Raspberry Pi Camera - 2 meters [ADA2144]

If you are an RPi n00b like me, it's good to make sure the software and hardware and cables are all OK with the small cable first. I'd never used this kind of ribbon cable and connector before, and that tripped me up at first.

Also if you get a longer cable, do not put it into a tight coil. Along the lines of @JayEye's answer, you may change the transmission line characteristics. I was able to make loose coils to take up a little slack.

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There's a clever pair of interface boards you can buy from tindie.com that lets you extend the length using a standard HDMI cable. Obviously the signal is not HDMI it just uses the wires. They claim success with a 5m cable.

The current page is here

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It depends on the environment the camera is operating within.

Some people have had success with 4 metres (probably more, I haven't looked through the whole thread again).

See https://www.raspberrypi.org/forums/viewtopic.php?p=362714#p362714 for stories and potential vendors.

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Yes, go to Adafruit.com (among others), they sell longer cables. But there are disadvantages to going too long. You could pick up another Pi or Zero to put at the camera and put them up to about 100 meters apart then link them over ethernet or WiFi. You could really use about any kind of computer to control it as long as the hardware and software are compatible. Look into gphoto to see what it can control remotely, they keep adding capabilities.

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