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HW failures on Canon Compacts

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Re: HW failures on Canon Compacts
« Reply #10 on: 22 / July / 2014, 09:59:45 »
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Do Tv overrides of 1.0 or 0.1 do anything?
Yes, 0.9 gives total over exposure => white JPEG.
Almost like the gain control is gone on the readout amplifiers.  Probably another camera not worth fixing then.
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Offline koshy

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Re: HW failures on Canon Compacts
« Reply #11 on: 22 / July / 2014, 10:04:16 »
The sensor is being exposed to light while the charge is read out.
Yes that could explain the different light levels on the lines.

Probably another camera not worth fixing then.
Absolutely. Got a battery and a charger. One could use it for spare parts for anything but the lens/shutter unit I guess but I'm not into that.
My interest is academic. I saw this error description (stipes) on used amera offerings before.

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Offline srsa_4c

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Re: HW failures on Canon Compacts
« Reply #12 on: 22 / July / 2014, 11:54:07 »
A quick look at uninterpolated data is interesting, too. On the white flower pot to the left of my original crop we can observe that there is a difference that spans over 4 sensor lines and then starts over. It seems to start very bright and get gradually darker three times and then starts over.
The effect is caused by "N-field readout" (the term "field" comes from Sony CCD product announcement documents) where N is the number of fields specific to the device.

If the camera takes acceptable pictures in total darkness with flash and video mode is OK, then the CCD and its related circuits are probably OK, the shutter flex cable is the usual cause of these symptoms.

edit:
One more thing: heavy overexposure might be the result of the loss of ND filter control (the ND filter wires are on the same flex cable).
« Last Edit: 22 / July / 2014, 12:06:09 by srsa_4c »

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Offline koshy

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Re: HW failures on Canon Compacts
« Reply #13 on: 14 / August / 2014, 13:12:56 »
Speaking of HW related issues... I have several A Series cameras where the battery doors are damaged in a way that they need to be held shut or taped shut when using the cam. Sometimes a little pin on the main camera body is broken, sometimes just the door. Has anyone gathered experience in fixing this kind of thing?

The I50 and A430 we spoke of before have been replaced. So I can start operating on the two spare ones...

If the camera takes acceptable pictures in total darkness with flash and video mode is OK, then the CCD and its related circuits are probably OK, the shutter flex cable is the usual cause of these symptoms
In total darkness with flash the results were fine. Can this shutter flex cable be replaced? Is there existing information on how to disassemble the I50 so far that one gets to the thing somewhere?
« Last Edit: 14 / August / 2014, 13:14:45 by koshy »


 

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