need help mounting usb camera

[Matt Graham]

After a long battle with technology, Alex Dean wrote:
> Xubuntu 7.10 on a Thinkpad T40.  Trying to connect a Canon Powershot A40
> camera. I'm plugging in the camera, and it's not mounting automatically.

Good.  Automounters generally cause more problems than they solve.

> 'lsusb' makes it appear that the system knows the camera is there.  I
> see device files in /dev which seem to correspond to the camera.  Same
> information shows up in dmesg.
[rearranged for clarity]
> alex at moosedrool:~$ dmesg | tail
> [44597.812000] usb 2-2: configuration #1 chosen from 1 choice
> [44897.276000] usb 2-2: USB disconnect, address 7
> [44939.524000] usb 2-2: new full speed USB device using uhci_hcd and
> address 8

uhci_hcd?  Do you have ehci_hcd loaded?  You want to use that if possible, 
since USB1 is slow.

If this thing were a Mass Storage device, you'd see some lines like so after 
the config bits:

scsi10 : SCSI emulation for USB Mass Storage devices
usb-storage: device found at 14
scsi 10:0:0:0: Direct-Access     Apple    iPod             1.62 PQ: 0 ANSI: 0
sd 10:0:0:0: [sdg] 12000555 512-byte hardware sectors (6144 MB)

...obviously, the iPod's a Mass Storage device on /dev/sdg (partition listing 
snipped for brevity.)  Remember, not all cameras act like Mass Storage 
devices.  Some can, but they need to be put into Mass Storage mode by 
flipping a switch (read your camera's Fine Manual to find out if that's the 
case.)

Some can't, and they use various protocols to transfer pictures to other 
devices.  (Why?  Mostly because of sheer cussedness, but also, Mass Storage 
doesn't have provisions for doing things like "take picture".)  Not all of 
those protocols are documented and there are about 300 different variants of 
each protocol.  Programs like digikam understand many of those protocols, so 
digikam or gtkam would be my first choice.  digikam has a listing 
for "Powershot A40" so it's entirely possible that gtkam has one too.  HTH,

-- 
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Matt G|There is no Darkness in Eternity/But only Light too dim for us to see