I'm not having any luck using either the gphoto CCD or the Canon DSLR driver in INDI.

I'm running on an Asus Tinker Board (like a Raspberry Pi, but a little faster), which is based on Debian 9 (Stretch) rather than Raspbian or Ubuntu. The Ubuntu Xenial kstars-bleeding repository seems to be the best match (requires the least shoehorning of packages) but I can't rule out that there's some incompatibility somewhere with that. I last upgraded tonight. I tried libgphoto2-6 2.5.22 from Debian unstable for a bit but it didn't help (or hurt, really) so I downgraded back to 2.5.12.

I'm able to use gphoto2 to manually control the camera and take a picture.

Both drivers just hang on capturing an image. I've tried with and without mirror lockup and with and without bulb mode. I get "Event timed out" messages in the logs. The Canon DSLR driver often crashes on startup. Both drivers keep prompting me for the resolution and pixel pitch settings, and they don't seem to get saved. I see a log entry that says "Driver indi_canon_ccd: indi_canon_ccd dispatch error: Cannot set read-only property CCD_INFO".

What else can I try?

Logs are attached for the Canon DSLR driver output.

Here is gphoto2 --summary output and lsusb output:

$ gphoto2 --summary
Camera summary:
Manufacturer: Canon Inc.
Model: Canon EOS 70D
Version: 3-1.1.1
Serial Number: e8361dc9f34246b6b2c8ef0bd1055e41
Vendor Extension ID: 0xb (1.0)

Capture Formats: JPEG
Display Formats: Association/Directory, Script, DPOF, MS AVI, MS Wave, JPEG, CRW, Unknown(b103), Unknown(bf02), Defined Type, Unknown(b104), Unknown(b105)

Device Capabilities:
File Download, File Deletion, File Upload
No Image Capture, No Open Capture, Canon EOS Capture, Canon EOS Shutter Button
Canon Wifi support

Storage Devices Summary:
store_00020001:
StorageDescription: SD
VolumeLabel: None
Storage Type: Removable RAM (memory card)
Filesystemtype: Digital Camera Layout (DCIM)
Access Capability: Read-Write
Maximum Capability: 128680198144 (122719 MB)
Free Space (Bytes): 101461524480 (96761 MB)
Free Space (Images): -1

Device Property Summary:
Model ID(0xd049):(read only) (type=0x6) 2147484453
Property 0xd402:(read only) (type=0xffff) 'Canon EOS 70D'
Property 0xd407:(read only) (type=0x6) 1
Property 0xd406:(readwrite) (type=0xffff) 'Unknown Initiator'
Property 0xd303:(read only) (type=0x2) 1
Battery Level(0x5001):(read only) (type=0x2) Enumeration [100,0,75,0,50] value: 100% (100)

Bus 001 Device 011: ID 04a9:3253 Canon, Inc.
Device Descriptor:
bLength 18
bDescriptorType 1
bcdUSB 2.00
bDeviceClass 0 (Defined at Interface level)
bDeviceSubClass 0
bDeviceProtocol 0
bMaxPacketSize0 64
idVendor 0x04a9 Canon, Inc.
idProduct 0x3253
bcdDevice 0.02
iManufacturer 1 (error)
iProduct 2 (error)
iSerial 0
bNumConfigurations 1
Configuration Descriptor:
bLength 9
bDescriptorType 2
wTotalLength 39
bNumInterfaces 1
bConfigurationValue 1
iConfiguration 0
bmAttributes 0xc0
Self Powered
MaxPower 2mA
Interface Descriptor:
bLength 9
bDescriptorType 4
bInterfaceNumber 0
bAlternateSetting 0
bNumEndpoints 3
bInterfaceClass 6 Imaging
bInterfaceSubClass 1 Still Image Capture
bInterfaceProtocol 1 Picture Transfer Protocol (PIMA 15470)
iInterface 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x81 EP 1 IN
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0200 1x 512 bytes
bInterval 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x02 EP 2 OUT
bmAttributes 2
Transfer Type Bulk
Synch Type None
Usage Type Data
wMaxPacketSize 0x0200 1x 512 bytes
bInterval 0
Endpoint Descriptor:
bLength 7
bDescriptorType 5
bEndpointAddress 0x83 EP 3 IN
bmAttributes 3
Transfer Type Interrupt
Synch Type None
Usage Type Data
wMaxPacketSize 0x0008 1x 8 bytes
bInterval 10
Device Status: 0x8ce8
(Bus Powered)
Debug Mode

Here are the GPhoto CCD logs - it crashes similarly on startup. This stands out in the logs:

DEBUG 3.809819 sec : Requested CCD Frame is (0,0) (0 x 0)
ERROR 3.809850 sec : Invalid frame requested (0,0) (0 x 0)

But I'm not sure what to do about it. In the CCD dialog box, even after filling in the camera resolution and pixel pitch in the popup dialog that comes up, Frame X/Y and Width/Height are set to 0 and can't be edited.

Be nice to see what the answer is to this, I had exactly the same problem with a Nikon D3200 DSLR.

Using the bleeding edge drivers, Ubuntu Mate, the camera would only take 1s exposures. Anything above, the camera would hang and timeout.

I tried:
Set the camera to bulb mode, with mirror lock off
In Indi, turn 'Force Bulb' mode off.
Entered Sensor resolution, Pixel Pitch settings.

After this, in EKOS setting an exposure of 1s with multiple exposures, the camera ticks away quite happily. above 1s, it hangs on the first exposure and doesn't recover.

Be useful to know if you try the settings above whether you get a different result to me?

In the end, I gave up and switched to using a programmable remote which works fine, but I'd still like to get things working in EKOS if possible...

I think I may have solved my problem. There's a lot of testing I have yet to do, but this is very promising. The Canon driver no longer crashes on startup, the image width/height that I enter into the popup dialog box propagates through to the CCD tab in the INDI control panel, and I actually got it to take a picture.

The fix was:

1. Add the mutlaqja libgphoto2 Ubuntu PPA to sources.list (I did not know about this earlier)
2. Upgrade libgphoto2-6, libgphoto2-port12, gphoto2 packages to this version.

You'll want to install indi-gphoto too, but since this is all built for Ubuntu Cosmic, it has a dependency on libraw16 which in turn requires too much stuff to be upgraded to post-stretch versions, so I decided to build it from source instead:

3. Grab the libraw Debian package sources (I used the 0.18.8 ones from Ubuntu bionic-security, actually) - .dsc, .orig.tar.gz, and .debian.tar.xz.
4. Install debhelper 12 from Stretch Backports
5. Install other build dependencies and tools (devscripts, fakeroot, libtool, autoconf, automake, autopoint, m4, libsigsegv2, perhaps others depending on what's already installed on your system)
6. dpkg-source -x libraw_0.18.8-1ubuntu0.2.dsc
7. cd libraw-0.18.8
8. debuild
9. Install the libraw16 package that pops out
10. Install indi-gphoto

Now I'm wondering if I possibly had an old (non-kstars-bleeding) version of indi-gphoto installed.

Unfortunately I think my problem is different from yours Wilkinson - I have yet to test long exposures at all, I was getting this when taking the default 1-second test shot.