Another a590is original firmware/electronic? shematic problem the battery monitoring.
I not know other canon cameras has this problem. The main problem, the sort working time.
I test the camera with powered the laboratory power supply unit (of course, this unit output voltage highly stabilized).
The camera working properly wide range voltage. Of course, do not use high voltage and/or any unstabilized power supply, possibly DAMAGE the camera! I test 2,4 volt (2 AA NiMh cell nominal voltage), everting is ok, and CHDK battery indicator says approx. 2.400volt. The original canon adater has 3.15 volt output. When use this, the CHDK says approx. 3.15volt. I think this is a maximum voltage (equal approx 2 fresh, high quality alkaline battery voltage). The camera working properly 2.000-3.150Volt. With 2.000 volt, everything is stable, and CHDK says approx. 2.000Volt. The camera must be down about 1.950-2.000volt automacilly. This is ok, NiCD, NiMH, and alkaline 2 cell normal end voltage is same.
The camera often switch off and says need to replace the baterry. If the voltage around 2.000Volt this is correct.
But, the camera switch off often, when the voltage is 2,3-2,6volts! This is abnormal! The original canon battery indicator often false. This blinking, when i use fresh charged accu! The measured voltage normal! Long piece picture recorded normally. In electronic market, lots of camera use voltage limit sensor, to switch off the camera. The voltage limit often 2.000 volt this is ok. Under voltage icon set to 2.1-2.2Volt. This method, simple, useful, safe, and has a largest working time. Canon cameras not use this method. This is very stupid. I think, canon firmware(?) check the voltage, and the time, how many volts dropped in fix. time. If the power voltage rapidly lower, the camera switch off. This method very wrong!
See the link with second graph, tipical NIMH cell, with average discharge current.
http://www.powerstream.com/4_3.htm When use fresh, fully charged cells, the voltege drop rapidly for several minutes, after the voltage near constans long time, near the cell empty, the voltage drop rapidly again. The cells fully discharged, must be off the camera, and need charging. The voltage drop speed relate with the cells internal resistance, and factory parameters, and the cells age, etc. But, this cells, ok. After use the cells 10-20 etc. this parameters wornger, but good too power the camera.
Canon firmware, often off, when i use fully charged cells, canon think, the cells empty, the voltage drops RAPIDLY, NO! The cells near new! After switch off, i discharge the cell about 10% on another camera. Next, i put to orginal camera, now, one hour! video recorded perfectly with LCD display ON! If the user try charge the canon "need to charge" cells, possibly over charge. Over charging danger to cells. Parameters wrong, the life time sort!
The question, possibly kill canon switch off method, battery warning icon? Possibly add correct, only voltage limit switch of method? Another camera users, this problem exist?
