[Nokia Lumia 1020] motoi_bogdan:
I've noticed some people have encountered this problem. Simply put, the camera can't focus properly at objects situated at about 2-3meters or further. Autofocus can succesfully occur only at macro shots. Sometimes this is coupled with that infamous camera scratching sound, the one that sounds like a dying penguin or whatever. :p

Well, my phone does all of this and since it's a second hand unit without any warrany, why the hell not, let's fix it. A new sensor is expensive so i had to find other ways to fix the one i have.

After some investigation is seems that the internal construction of these sensors includes a mobile assembly containing the OIS and autofocus mechanical and optical modules. When you focus - relative to the sensor underneath, the lens have about 1.5-2mm travel space, again, relative to the sensor (that's fixed in the frame). When you focus the camera to an object far away, the lens assembly must travel inwards, closer to the sensor. Viceversa, when you focus for a macro shot, the lens travel further appart from the sensor. Pretty simple.

However, all but one of the lens are made from polycarbonate (plastic) like most of the sensor module's guts. This is not a bad thing actually. The choice was made because the optical assembly must be as light as possible and glass+metal would have weighted a lot more. But using plastic has some other problems.

When i disassembled the phone, i extracted the sensor module and activated it outside of the phone casing to make some tests. What i first noticed is that as soon as i enable the camera app, the sensor will get hot. Real hot. You can't touch it after some 2-3 minutes of it running. Most of the heat is generated by the photo sensor itself. It's how these things work. However the heat output from such a huge sensor is more disturbing then the situations found with other phone's small camera sensors. Even so, for example, it is known that HTC One M7 had a failure mode involving it's camera, due to the high heat output, the sensor would burn itself resulting in a pink/purple cast over the image you try to capture. Over time those sensors will fail, HTC replaced them with a different design.

In lumia 1020's case the huge heat output results in a another failure mode. Since the module uses gyroscopes and moving parts (bearings, actuators etc) in plastic rail, the plastic becomes brittle with an increase in temperature so the rails change their position relative to the sensor. So it's mechanical wear amplified by overtemperature.

The aufocus lens subassembly will actually swing out of the correct focusing distance. The 1.5-2mm distance will thus increase over time. Since it's a closed space, there's not enough space to accomodate the new lens position, so at some focal lenghts the mobile assembly will bash against the sensor casing resulting the dead penguin sound.

SO..... HOW TO FIX THIS?

If your phone's camera does the penguin sound all the time, then it's done. It's past feasable repair solutions. If it's only seldom happening or only at specific focus distances, you could still be good to go. Also, no penguin sound but only focus problems is the ideal case.

So, what to do. It could come as a surprise but if it were a human, your phone would have a typical case of short-sightedness or myopia. So... let's treat this condition like we would do with a human.

First step: find some glasses. From some experiments i've determined that my phone has a -2 to -3 myopia. So i found some corresponding glasses, placed one lens over the sensor area and voila : the phone now focuses properly. I can take a landscape photo.

So, with that in mind, find some lenses, specified for -2 to -3 myopia and check them with your phone. Try taking photos without using the flash at both landscapes and macro things. A good lens is one that enables the phone to focus at both macro and landscape. Larger negative value lens (-4 -5 etc) could correct landscape focus but prevent the sensor module to lock a macro focus. So.. experiment.

Second step, the ideal lens should be made from polycarbonate, not glass. You will need to cut the center of the lens itself. You can't cut glass with regular tools. If you find the right lens, proceed to disassembe the phone. Once you remove the sensor, you will see a glass lens glued to the back of the phone's casing (on that round black circle on the back). You will need to find a way to replace that lens with your new found one. Ideally, the piece of lens you cut should be as flat and thin as possible in order to make a flush fit inside the casing. Before glueing anything test the lens at the distance it will be mounted over the sensor. If everything is right, remove the original lens using some hot air (it's glued) and replace it with your custom one.

Third step. Improve the sensor's cooling. Some cooper pads should be already placed there by the manufacturer. Use the back of the screen as a cooling surface. Place cpu thermal compound (arctic silver, any good brand) over those copper pads and check to see if they make contact with the back of the display. If not insert some aditional copper pads. This will prevent further heat related problems and further sensor module damage.

Also... NEVER USE FLASHLIGHT APPS FOR TOO LONG WITH THIS PHONE!. When you use them, you are actually powering up the whole sensor not just the led. This can result in overheating and premature damage to the sensor itself.

I have completed my preliminary tests so i'm now searching for a good lens to place inside the phone, once i find one i'll update this post and ad a picture tutorial.

Meanwhile, feel free to experiment by placing different glasses in front of your phone's camera ( 1cm or closer) and check to see what works for you.

Hope it helps :good: