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Apple Firewire I-sight Hacking:

Here i will describe how to take apart Apple's i-sight firewire webcamera without damaging any of the components. Note that by working backwards you can also put the camera back together again and it should still work just fine. I have done this (take apart/put back together process) at least three times with great success.

Getting it open:


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The first step is to remove the two screws that secure the aluminium housing. Next, lift the white plastic rim by pushing the long side of the ellipse toward the back of the camera.


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To remove the aluminum housing start by pushing on the backend of the camera about a half inch. Then grab the camera from the front and pull.


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As you pull the camera through, the back should pop off easily.


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The next step is to peel away the black mesh surrounding the camera body. I recommend using tweezers in case you want to put the mesh back on if you plan to reassemble.


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Once the mesh is lifted, roll the camera away holding the mesh down flat on the table until you see the two microphones. I found that doing it this way best preserves the adhesive at the edges of the mesh.


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Once the mesh is removed you will see three screws near the front of the camera toward the edge of the lens cover.


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After removing the three screws, the next step is to snap apart the camera's black frame. For this step I hold the camera with the lens pointing toward my left side. I use my left thumb (as shown in the photos) to unsnap each of the three tabs moving left to right for each tab. Sometimes you may have to push the three tabs in sequenece a few times to get it to open cleanly. Don't push too hard because you don't want to break the tabs.

Done correctly, the black frame sould come apart easily.

Examining the Sensor and Aperture Assembly:


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The first thing to notice is that the camera's sensor is connected to the board with an internal ribbon which has 26 pins. The ribbon has a 13mm width giving it a pitch of 0.5.


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At the back of the camera we see a chip that is connected to the main board. I was curious whether this chip could be removed (with the camera still being functional) in order to minimize weight and size. I tested the camera without this board and, not surprisingly, the camera did NOT work. You need this board.


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Before removing the aperture ring, you'll notice a small, four-pin, ribbon cable that connects to the camera's main board. This cable connects to an infrared optical switch that is build into the i-sight's aperture. As you turn the aperture to close it a piece of plastic trips the optical switch and the camera turns off. I tested the camera with this ribbon unplugged and everything works fine, but (obviously) you can't turn the camera on/off with the apture ring.


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The next step is to remove the lens aperture from the lens module. To do this remove the three screws as shown in the images above.


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PLEASE NOTE: Once you take off the backing ring the aperture assembly will be exposed. I found this to be very tedious to put back together so pay careful attention to how the three aperture leaves are placed inside of the camera when you pull it apart. Unfortunatly I did not docucment this part of the process.

Once the backing ring is removed, you'll see a small, rectangular groove (as pointed to in the picture). On the mating plate there is a small arm that serves to "break" the optical connection. You can also see a small metal "tongue". There are two notches on the mating plate that correspond "on" and "off" positions. This tongue simply acts as a spring that snaps into one of the two notches.

The Auto-focus Ribbon:


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The above image shows another 7-pin ribbon cable that is attached to the camera's sensor board. This ribbon controls the auto-focusing motor housed inside the lens assembly. During this investigation it was clear that the i-sight's really has only two focusing positions (near and far). Apparently some processing is being done on the board that can focus the lens when the camera is pointed at an object or scene with high spatial frequency.

In some applications you might not want this auto-focusing feature, and there is no external switch to turn this on or off. However, I did test the camera with this ribbon unpluged and the camera worked normally, but without auto focus. Since you cannot manually focus the lens, one solution might be use the auto-focus during a preliminary setup and then unplug the ribbon once the focus is correct. The camera's lens will remain in that position until the the ribbon is pluged in again. NOTE: It turns out with the newest version of Quicktime and the latest i-Sight driver you can turn off the auto focus in software, but you must do this each time you start the camera.


Sensor Board and Infrared Blocking Filter:


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The next step is to detatch the lens assembly from the camera's sensor board. To do this you need to remove three screws.


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The lens assembly is removed to expose the raw image capture sensor.


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The infrared blocking filter is easily removed in two steps. First the foam square is taken out with a pair of tweezers and then the IR bolcking filter is easily removed. Note that this is a great feature of the camera as compared to other cameras that glue the filter directly to the lens or sensor. The disadvantage if taking out this filter is that it changes focus due to the change in the index of refraction. One solution is to buy or cut a piece of clear glass the same thickness and then you will have the correct index for focusing. You would then have a handy firewire infrared camera!


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Notice how small the lens assembly is. I did not venture toward taking apart the autofocusing mechanism because I was concerned that the small springs and gears would make it difficult to put it back together again.

 
     
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