Well i am just cooking the dinner (making my head to breath a bit out of gphoto & rpi3 !! loool) - i will look better your inputs in a few...
my morning message was related to the issue i open on GIT regarding gphoto2 in fact, where i attached the debug file.
You can read the exchnage and see the file there :
(i just recently send a new message with the new debug file...
the "unknow event" is trange but i see them also when it is a success with the jpg. The trouble is after that and after the exposure...
I am right now trying to install a ubuntu astro (astronomy linux distrib) to a hardrive and i will try it on my laptop (to see if the laptop has same issue this would take out the rpi3 possibilty)
hoping Marcus or other people could check from gphoto2 side ..
I will come back to your message later tonight
thank you very much for taking time to look & remember your experiences