Tuesday 13 March 2012

6 LED webcam with microphone

I just bought a "USB 30.0M 6 LED PC Laptop Video Web Cam Webcam + Mic" on eBay, which (as I suspected) doesn't live up to its claims - 30 mega-pixels! Ha! Not that I expected much for £3 but still... it only seems to be 0.3 mega-pixels.
Example retailer's photo of 6 LED webcam

Currently searching eBay for "6 LED webcam" will give lots of listings at the moment which all appear to be the same model camera (some come in different colours, e.g. red). Some list the number of pixels as 12.0, or 16.0 with interpolation, whereas the supplier I picked put 30 mega pixels without the weasel words "software interpolation". There is no manufacturer's name given in the listings - some show a generic "PC Camera" box (mine came in a jiffy bag). There are similar looking examples on the Amazon Marketplace, e.g. this one claiming 20 mega pixels, and at Play.com, e.g. this one claiming 5 mega pixels, with minor differences in the writing on the focus ring or the base. It is possible the internals vary. The main board in mine is made by Etron Technology as determined by the writing on the chip (see below).

Under Linux, I could only get up to 640x480 pixels, which is 300k or 0.3 mega-pixels. It seems like the eBay seller is two orders of magnitude out by claiming 30 mega-pixels!
6 LED webcam
The writing on the lens says Megapixel 10X Digital Zoom f=3.85mm which would be fine if I could get even one megapixel out of it! That silver section on the top is a button - presumably to take a snapshot if your software supports it. The cable is as advertised 120cm (4 foot), the last 15cm (6 inches) of which are forked for the separate USB and microphone 3.5mm jacks.

What I thought looked interesting on this webcam was the six LEDs, controlled via a dimmer switch on the cable about 20cm (8 inches) from the camera. The dial is surprisingly sensitive in the range you might want to use it - and blindly bright at full power from screen distance. If you try adjusting this while using it for video chat, expect to suffer accidental afterglow on your retina for a while afterwards.
LEDs on LEDs off
The base works OK on a flat surface, but the "clip" is almost useless for attaching to a monitor or laptop screen. The trouble if is just free standing and you touch the LED dial the webcam is so light it wobbles and moves. Having the cable coming out of the back of the camera unit itself doesn't help either. Even trying to do the above photo without the webcam moving much was a pain!

I actually bought this to use on my work computer for occasional conference calls. Sadly it doesn't have a microphone input socket. It does have a line in socket, but it appears a microphone would need amplification to register anything. I guess I need a webcam with a proper USB microphone instead.

On the plus side, the claimed focus range from 3 cm seems true.

Testing in low light

These comparisons put this 6 LED webcam (left column) up against an unmodified Xbox Live Vision webcam (right column), under various lighting conditions. The images were captured using Apple's Photo Booth application (no control over settings).

6 LED webcam (moderate light, LEDs off)Xbox Live Vision (moderate light)
Notice the 6 LED camera has a narrower field of view, while the Xbox camera is more yellow looking. They both perform adequately on with moderate light, but the Xbox live looks a lot better with less light:
6 LED webcam (indirect light, LEDs off)Xbox Live Vision (Indirect light)
Of course, this is where the new webcam's built in LEDs come into play - so let's turn them up full and see what happens:
6 LED webcam (indirect light plus its own LEDs)Xbox Live Vision (indirect light plus other cam's LEDs)
6 LED webcam (light from its LEDs only)Xbox Live Vision (light from 6 LEDs only)
This is perhaps unfair - the distance is just over 3m and I'm sure that's more than the designers had in mind with the LED design!

Insides

Not being too worried about damaging it, I opened it up. The lens rim unclips, which also frees the silver plastic decoration under it. Then there are two small Phillips head screws holding the case together (one hidden behind a sticker). Remove them, and the two halves of the case open, freeing the top silver button, and the stand.

Opened, microphone top leftPCB front, showing sensorPCB Back, EtronTech eSP268
There is a small blue PCB taking six wires soldered and covered in glue. I presume the group of four are the USB cables (GND, +D, -D, VCC) while the extra pair connected on the other edge go to a variable resistor in the cable dial switch to control the LED brightness. There is also a small button switch which the silver top button connects to.

Also coming down the cable are two more wires (together in a blue cover) to a small 5mm or so cylinder which I deduce is the microphone (electrically this appears to be completely separate from the USB circuitry).

On the front of the PCB the lens unscrews to reveal it includes the red glass filter, and expose a very small image sensor.

The main chip on the back of the PCB reads: EtronTech eSP268A7 P254609 H6S247.11
 
This is how USB device identifies itself via the Mac command system_profiler SPUSBDataType:

            USB2.0 Camera:
              Product ID: 0x0102
              Vendor ID: 0x1e4e  (Etron Technology, Inc.)
              Version: 1.01
              Speed: Up to 480 Mb/sec
              Manufacturer: Etron Technology, Inc.
              Current Available (mA): 500
              Current Required (mA): 100

As expected from the claims of plug and play without drivers, this is a USB Video Device Class (UVC) camera. From a Google search with these USB IDs, it appears the same chip/sensor is also used in many other devices including a mini clip on webcam with retractable lead (and no microphone) and even a microscope camera! That fits with Etron's claims to have have shipped over 20 million of the eSP258 and eSP268 series webcam controllers since 2009 - achieving 50% of the PC Camera market share in China - you can read more about the Etron eSP268 here, which as also mentions a new eSP568 chip which supports a microphone via USB.

I haven't worked out who makes the CMOS sensor yet.

Conclusions

In most respects the Xbox camera (which costs about the same - both under £5 on eBay) is a clear winner - under Linux at least it has more pixels and does better under low light. In terms of the stand, the clip design is poor, and I find the Xbox camera works better than this one free standing. There is the microphone to consider (assuming you have a suitable port), but overall for me the only thing going for this webcam is the LEDs, and I'm not sure how useful they would be in practice. Finally, if you're considering this for a hobby project think carefully about the cabling requirements - you'd need separate extension cables for the audio and video.

Update (25 March 2012)

It looks like Maplins are now selling this as the 'Pluto webcam' for £10. Seems over priced, but they are very clear in the description that it has only a 640x480 pixel hardware resolution.

5 comments:

  1. i want to download the driver of this cam, how can i do this?

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    Replies
    1. This is a USB Video Device Class (UVC) camera, which means it should just work on any recent operating system. I didn't need extra drivers under Mac OS X or Linux - and it should work on recent versions of Windows too.

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  2. This is all good and well but how the heck do you adjust the terribly sharp lighting on it?. My friends are saying i am like a shining light when they view me. Is this webcam just totally rubbish, in which case i shall definitely buy something decent. Any answers here please?.

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    Replies
    1. Yes, this webcam is pretty rubbish. I never tried it an actual video call, but as I wrote about found the brightness control very fiddly - getting a good level of brightness is quite hard. But it was cheap, and might be fine for some hobby projects. Mine is now in bits, with the lens mount reused in a bird-box camera.

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  3. its fake mine is a kross one and the kross one is real

    ReplyDelete