Focus with chdkptp on ixus160 (was Re: Trouble solving, help in using CHDK PTP

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Hi, gurus!

Thanks for providing the build, it let us create a nice booth using ixus 160, but we still improving it as we can!)
So one small question:

We have installed CHDK latest build ( that was kindly provided by srsa_4c  couple of months ago, attached below.

As we understood our cameras are not supported in full by this build, as this is a beta version of the build.

We have 48 Ixus 160, all of them are controlled via PTP protocol that is utilised by Canon cameras only. To control and manage cameras we using  CHDK PTP.

The problem is no matter of the amount of light or any other factors each time we have  3--5 cameras out of focus, we using same settings for all cameras. Cameras has standard autofocus function switched on.

We tried as well to set fixed focus distance towards object using CHDK PTP.

For example, after connecting to all cameras we see that 3 camerad out of focus, using command-line we turn off autofocus and set it manually, we see that all cameras reacted to the comman but still same 3 out of focus, while others are in focus.

Only reboot helps to solve this issue for one shooting set.

Have you crossed something familiar during using this build? Could you please guide us somehow towards solving this problem? 
« Last Edit: 26 / December / 2015, 15:49:27 by reyalp »


Offline reyalp

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I split this to a new thread, since it doesn't seem related to Kestrel1978's question.

What specific code are you using to set focus manually?

Is it always the same cameras that have problems?

Have you verified that you can control focus with CHDK at all? I would suggest making sure everything works with just one camera before trying to troubleshoot a whole multcam rig.

Also, if srsa provided you the link privately, you probably shouldn't post it here. As noted in the porting thread, we want people to be aware of the history of camera damage from this port before installing.
Don't forget what the H stands for.

I have used IXUS/ELPH 160 cameras extensively. There is an issue where the camera autofocus begins to malfunction and every shot is blurry. This happens even with subjects and scenes that otherwise work fine. Turning off and on the camera is the only remedy.

It only affects autofocus. If a camera has its focus locked with AFL, I have never seen it happen. So if your usage involves fixed subject distance, you might have luck locking the focus once and bypassing the problem entirely.

This issue happens on occasion even when simply using the camera normally without CHDK installed. So I think this has to be considered a flaw in IXUS/ELPH 160 cameras that has to be worked around rather than anything that can be fixed via CHDK.



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