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How to shoot picture with not fully working camera?

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How to shoot picture with not fully working camera?
« on: 17 / August / 2010, 04:32:53 »
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Hello.
I have a SD630 A630 that have broken lens. On power up it showed E18 fault. I removed objective and replaced it with microcontroller that mimic objective action at startup. In addition I re soldered main board of camera with hot air.
My target is to attach camera to telescope for planetary photography. There is objective not needed.
So currently in playback mode everything seem to work fine. Camera respond to buttons, I can see pictures from SD card and so on. In shooting mode I see live view (sensor is working), CHDK run ok, I can use buttons in ALT mode, I can run script. But camera do not respond to buttons in "not ALT mode", I can't switch to play back, switch off camera, change shooting mode.... Also do not help if I write script that operate with buttons and do not respond to <shoot> command.
I need that camera is able change shutter and ISO speed, shoot, and record it in RAW.
Any idea is it possible?
« Last Edit: 18 / August / 2010, 05:56:50 by meelist »

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Offline fudgey

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Re: How to shoot picture with not fully working camera?
« Reply #1 on: 17 / August / 2010, 13:20:32 »
Sounds like your uC isn't emulating the objective well enough and something in Canon's firmware notices that. The camera romlog might give you an idea of the problem:

http://chdk.wikia.com/wiki/LUA/Scripts%3AStandard/Test/Romlog
http://chdk.setepontos.com/index.php/topic,5394.msg52313.html#msg52313

Re: How to shoot picture with not fully working camera?
« Reply #2 on: 18 / August / 2010, 09:22:42 »
I got that romlog.log. I tried many times and all they are same, even Occured Time is same. Question: is this log written every time after power-on or it remain same until new Exception occur?
I made also RAM dump. How can I compare it to PRIMARY.BIN?
« Last Edit: 18 / August / 2010, 13:51:20 by meelist »

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Offline fudgey

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Re: How to shoot picture with not fully working camera?
« Reply #3 on: 18 / August / 2010, 16:14:35 »
I got that romlog.log. I tried many times and all they are same, even Occured Time is same. Question: is this log written every time after power-on or it remain same until new Exception occur?

I'm not overly familiar with it, but afaik the camera romlog holds information regarding the last logged problem. Unless there's some way to clear it, only a new problem will write to it and running the romlog lua script output would always be the same. In your case a the camera should probably write to its romlog any time you go to REC mode, but maybe it doesn't since it doesn't actually crash. I believe the romlog starts with a datestamp of the incident, at least that's how it seems to be on my a570.

Even if romlog doesn't help, CHDK probably runs (you just can't command it since the camera buttons fail to work) and as such things like PTP might work and theoretically could be used to debug. Sounds like an awful lot of work, though.

I made also RAM dump. How can I compare it to PRIMARY.BIN?

RAM is RAM, PRIMARY.BIN is ROM, memory is either and both... but anyway I don't see why you'd want to compare the two, it's highly unlikely that your problems would be due to corrupt ROM instead of the obvious i.e. broken lens assembly.


Re: How to shoot picture with not fully working camera?
« Reply #4 on: 08 / September / 2013, 14:35:06 »
At last I managed to replace objective with simulator circuit. If anyone is interested about technical solution, I will describe it.

There is picture from modified A630 and first picture I made with it through telescope.

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Offline reyalp

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Re: How to shoot picture with not fully working camera?
« Reply #5 on: 08 / September / 2013, 16:32:25 »
At last I managed to replace objective with simulator circuit. If anyone is interested about technical solution, I will describe it.
Yes, we are always interested :)
Don't forget what the H stands for.

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Offline ahull

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Re: How to shoot picture with not fully working camera?
« Reply #6 on: 08 / September / 2013, 16:54:01 »
Interested #2... We want pictures of the build though or it didn't happen  :P

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Offline Davo

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Re: How to shoot picture with not fully working camera?
« Reply #7 on: 09 / September / 2013, 13:59:05 »
Quote
At last I managed to replace objective with simulator circuit. If anyone is interested about technical solution, I will describe it.

Very interested #3. Nice pic of M57. I would like to remove the lens from my A810 to use it at prime focus. Any pix you have of the removal would be appreciated.


Re: How to shoot picture with not fully working camera?
« Reply #8 on: 09 / September / 2013, 14:56:05 »
At first I explain how lens is working. Lens is connected to camera through flexy cable connector. On the cable are test pads. They are excellent place for soldering replacement circuits.

There you see lens circuit diagram.
Lens have next systems:
1) Zoom system: DC motor with two phase encoder and "home" sensor.
2) Focus system: two coil stepper motor and "home" sensor.
3) Aperture: two coil stepper
4) Shutter: electric magnet
5) 10k NTC for lens temperature measuring.

For fooling camera you need replacement for Zoom lens and Focus system.
Focus system: Power on starts with "home" optocoupler closed. Stepper is driven with 10us pulses. After 3000 pulses optocoupler is open.
Zoom system: Power on starts with "home" optocoupler closed. When motor is powered, encoder start giving pulses about 700us length. After few (about 100) steps "home" is opened.

to be continued ...

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Offline ahull

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Re: How to shoot picture with not fully working camera?
« Reply #9 on: 09 / September / 2013, 16:14:33 »
I have a couple of dead Canon cameras that "one day" hopefully will get hacked to operate without lens. I'll probably either attach to my microscope (although I already have an attachment for that for my A560), or use them as pinhole cameras.

Dead lens mechanisms cause the older canon models to turn up on ebay regularly, and I have a personal quirk, I never pay more than 4.04 GBP for them (geekiness in the extreme I'm afraid, the figure 4.04 comes from the 404 error you get from web servers).

I have quite a collection of fully functional cameras, all of which started off as 404s, but one or two are corpses without hope, and one of these may get the no lens treatment. I also have an Ixus 80 that I keep meaning to remove the IR filter from, but so far other projects keep getting in the way (fixing the carb. on the lawnmower and other necessary but boring projects I might add).

 

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