has been moved to section "SLR Camera Maintenance" at: How to do Safaris Photography. The article starts by:
One maybe astonished when faced with a malfunction on one's Canon EOS. the camera is not responding to trigger and instead of shooting a frame, a flashing message pop-up on LCD indicating “ERROR99”. Some start by questioning the battery, CF card and lens mount, but it may prove to be worse.
This error correspond to a failure in communication between the camera body-processor and camera circuit. It might be anything that interferes with the camera cycle which is (mount-trigger-shutter and recording): an unclean sensor for instance, dirty mounting triggers,shorting in power circuit, bad input/output CF card or, which turned to be my case: bad shutter mechanism.
Because of depreciation, one may lose the pushing gear of the shutter and that will interfere with the cycle and will result back in the error. Normally a shutter can be fixed, according to lots of online-reviews, but since it’s the most moving element within the body, one usually get a recurrence of error in case of fixing. You may wish to replace the camera body!
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