Camera Troubleshooting

Points of failure

In order for proper operation of the DFN observatory a few things need to happen:

• The observatory box must be powered - LED indicator are lit (at least on the micro controller PCB)
• The embedded PC must boot successfully - how to troubleshoot
• PC has to tell micro controller to power on
• DSLR has to power on
• PC has to tell microcontroller to start taking images
• Microcontroller has to trigger camera through optocoupler and shutter cable
• DSLR has to be configured properly to take photos via gPhoto2 over USB
• DSLR has to take photos - how to fix

Initial Steps

The first task is to figure out what's not working, starting with the most likely and easiest to check steps. If that doesn't work then we can move on to the trickier steps later.

Are the drives full? Try df -h to see how full they are. This will list a percentage full for all partitions (but not the external drives if they aren't powered on and mounted).

How to troubleshoot PC booting

1. Power on the observatory box and try to locally connect with ethernet cable or WiFi (if the box is is equipped with it, eg DFNEXT type)
   • for wired connection, make sure you using the correct ethernet port for laptop connection. (Better try both if unsure.)
   • make sure the WiFi antenna is attached if you want to use WiFi - the white little stick on the bottom of the DFNEXT box.
   • remember it may take a few minutes to boot the camera OS since powering it on
   • for wifi, the observatory is by default configured as an access point (2.4GHz 802.11g), with SSID same as the observatory host name, eg DFNEXT014 - try scanning for this SSID.
   • you can try ping the corresponding IP address first before ssh connection - for wired

   ping 172.16.1.101

   or for wifi

   ping 172.16.0.101

2. If the previous step fails:

   It is possible that the filesystem got corrupted and the booting process is stuck at filesystem check & repair. That can happen if the observatory system was earlier powered off (unplugged) without shutting down the OS properly. In that case user keyboard interaction is required, so you will need to:

   • connect USB keyboard
   • connect monitor (HDMI works with all cameras, some DFNSMALLs support also VGA)
     please note that the monitor in most cases must be plugged in before powering on the camera. If the camera is already powered, connect the keyboard and monitor, hit Ctrl+Alt+Delete at least seven times and wait for the box to reboot. Only if that is not working, power off and power on the box to enforce reboot
   • follow the instructions you will see on the screen
     root password will be required, then it is mostly hitting 'y' key

Possible cause & fix when DSLR is not taking photos

power on the DSLR (or stop interval control service if running)

run command "lsusb", should list device like

Bus 002 Device 004: ID 04b0:0436 Nikon Corp. 

if not, visit te site and check the wiring - USB data cable and power cable to the DSLR

if listed, run command "gphoto2 --capture-image-and-download"

if you get response

*** Error ***              
Camera Mode Not Adjust FNumber
ERROR: Could not capture image.
ERROR: Could not capture.

that means the Aperture ring of the Samyang lens is in wrong position. Set it to F/22 (which printed in red)

• Photos have to be downloaded to the PC via gPhoto2 over USB
• Photos have to be stored in /data0 and renamed properly by the DFN's capture control software
• Photos have to be copied over to /data1, /data2 or /data3 by the data move script