So the good news is that although this problem's been happening for weeks, this morning both intervalometer and USB trigger scripts are now running fine (for a couple of minutes).
The bad news is I hadn’t yet tried implementing any of the solutions outlined, so the problem may well come back, in which case I'll try the steps you've both suggested and report back.
With regards to your useful list of 'possible causes' list Waterwingz:
1. SD card problem - rereading this thread I don't see you mentioning trying another card.
I have tried with another (identical) card, but the intermittent problem persists (see initial post).
2. Camera hardware problem. That would suck if true
Agreed, so I’m going to see if the problem stays away and if not then exhaust all other options before resorting to buying a new camera.
3. Camera setup issue - some Canon shooting / focussing / exposure / scene mode you are using that triggers these issues. You could try a camera reset via the Canon menu entry that says "Reset All.."
Sounds sensible, I’d try this if the problem hadn’t disappeared.
4. CHDK setup issue - some CHDK mode you set (maybe by accident while learning) that triggers these issues. You could try a CHDK reset via the CHDK Settings menu -> "Reset Options to Default..."
Sounds sensible, I’d try this if the problem hadn’t disappeared.
5. User error - something in how you are setting up & using CHDK that you don't realize is different / problematic.
Certainly possible; however, in reviewing the steps I took to determine my camera specifications and install the CHDK originally I haven't found anything I missed.
6. Problem with the CHDK port for the SX260.
That had occurred to me, as it would seem a reasonable explanation; however, I’ve seen many others using CHDK on SX260-HS over the last few years without any reporting this issue. Is it possible to record some kind of log file, to help us narrow down what exactly causing this error (maybe this would help clarify whether the issue stems from the port…)? EDIT: I think this is what's been suggested by srsa_4c, again, I'll try this if the problem reappears.
7. Problem with your script. I think you mentioned trying other scripts though?
That’s correct, I have tried several different scripts (including several in widespread usage, many of which already include a sleep term of 50 to 1500 ms), and the issue persists.
Thanks for the input srsa_4c. AFAIK the SX260-HS doesn't have an Eco Mode (this is touted as one of the big improvements of the SX280-HS...), but it might have an equivalent which would explain one of the problem behaviors (although not why it's intermittent). If my problem returns, I'll try enabling the logging you've suggested, and report back.
(on a side note, just hoping to clarify best practice, I've seen several users on the DIY Drones forum state that Canon’s built-in Image Stabilisation [IS] cannot correct for with the vibration properties of multicopter airframes, and therefore, somewhat counterintuitively, when enabled it often actually degrades image quality. This contrasts with the advice I seen several times in this forum, where IS is recommended to help manage UAV-associated vibration issues).
Thanks, Andy
