This was sent in PM, but seems more suited for general discussion
i´m trying to make a timelapse with my IXUS 750. Rawopint works great on the camera and i also can start it over a raspberry with chdkptp and .loadfile. The only problem i´ve got is the SD card. The "old" IXUS 750 only works with "standard" sd cards, so i´m limited to 2gb.
My solution/wish with chdkptp:
start rawopint and take one picture (loadfile)
download the picture to the raspberry (imdl)
delete pictures (imrm)
restart after x seconds
Question:
The values get lost when the rawopint script ends. Is it possible to save and load the values from previous made pictures?
maybe from rawopint.csv, or do you know an other workaround?
That's an interesting question and an application I hadn't considered.
This capability doesn't currently exist. If you have some coding skill, you could look at the simulation code. I haven't kept it up to date with rest of rawopint so it doesn't currently work, but it does show loading the values from a rawopint.csv log. rawopint treats the first exposure specially so loading the values is only part of the solution.
Some other suggestions:
* Instead of 1 shot a time, do ~1000 images (or whatever your card can hold if it's less). There would still be some gaps and variation between segments, which may or may not be OK for your purposes
* Get a camera that supports SDHC. You should be able to pick up a slightly more modern camera on ebay, amazon etc. pretty cheap. Note however that if you get more than about 1000 images on a card, PTP control and transfer becomes impossible (this is a limit of the Canon firmware, it just displays "connection error")
* Convert rawopint to use PTP remote capture, so it saves directly to the raspberry pi. This should only require minimal changes in rawopint (mostly just calling init_usb_capture), but you'd need to write supporting code on the chdkptp side to receive the images. I might be convinced to add the chdkptp side support for this, since a general "receive images from a camera side script" option seems like it would be useful. This might still need to switch to playback or reboot periodically to avoid the 1000 image limit.
* Use a wifi enabled card that supports auto delete. However, I suspect most are SDHC these days.
* 4GB SD cards (not SDHC) cards do exist, so if you don't need a lot more, that could be an option. They might be comparatively expensive and hard to find.
* If you don't need the kind of speed and exposure control rawopint provides, you could try the pi controled multilapse script discussed in
https://chdk.setepontos.com/index.php?topic=13261.0 or waterwingz "ultimate"
https://chdk.setepontos.com/index.php?topic=9969.0 which has some options for periodic PTP downloading.