No bulb_widget is found. Is that supposed to be the case? The 20d does not support eosremoterelease. Bulb is a "shutterspeed" with the 20d.
The software should not get to the point where it is comparing selected exposure time vs. the cam's exposure list calculating a delta. It should check whether "bulb" is a setting in this list and choose the correspoing best_idx = 0.
Our messages crossed. There is a May 2017 comment in the gphoto_driver.cpp code (related to ram/sdcard problems) that mentions the 20d. I believe we had been working with the 20d before and I would be shocked to find out that was not in bulb mode. I'll check whether I can find older messages related to the 20d.
Does merely setting shutterspeed index to 0 (bulb) begins a bulb exposure? Please try that, and if it indeeds trigger the exposure then I'll update the code accordingly.
Looks like my impression is wrong and I had not taken long exposures with the 20d running Kstars/Indi in the past. I'm sorry for the troube I might have caused and formally apologize. Is there a way to work around this? Does anybody have experience with an external shutter release that supports bulb mode and can be triggered by Indi?