如何为正确的应用安装数码相机？

每当我插入数码相机时，就会弹出一个漂亮的媒体图标。伟大的！！

当我右键单击此图标时，我只能打开 Rhythmbox 或 VLC-media-player。在这里使用这两个应用程序都是毫无意义的。当我想下载照片时（无论是通过 F-Spot、Shotwell 还是 Picasa），我必须先卸载相机。这在我看来相当不合逻辑？如果必须卸下相机才能使用，为什么还要安装相机？如何使数码相机安装在正确的应用程序中？我觉得很奇怪，必须先卸载设备才能使用它！

相机型号：佳能 PowerShot SX20 IS（已在 libgphoto2 2.4.9 中为此相机添加了新 ID。packagemanager 告诉我安装了 libgphoto2-2，版本 2.4.8-0ubuntu2 => 看起来 libgphoto2 无法读取相机？无论如何，PTP/MTP-模式工作正常）

uname -a
Linux Ubuntu-Bernard **2.6.32-24-generic #42-Ubuntu** SMP Fri Aug 20 14:24:04 UTC 2010 i686 GNU/Linux

cat /etc/lsb-release
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=10.04
DISTRIB_CODENAME=lucid
DISTRIB_DESCRIPTION="**Ubuntu 10.04.1 LTS**"

lsusb
Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 005: ID 04a9:31e4 **Canon, Inc.** 
Bus 001 Device 003: ID 0b05:1706 ASUSTek Computer, Inc. WL-167G 802.11g Adapter [ralink]
Bus 001 Device 002: ID 050d:0234 Belkin Components F5U234 USB 2.0 4-Port Hub
Bus 001 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub


Type filesystem = **gphoto2**

KernelLoggings (plug-in/plug-out)
Sep 11 19:23:55 Ubuntu-Bernard kernel: [ 1370.156803] usb 1-2.1: new full speed USB device using uhci_hcd and address 4
Sep 11 19:23:55 Ubuntu-Bernard kernel: [ 1370.282419] usb 1-2.1: configuration #1 chosen from 1 choice
Sep 11 19:31:59 Ubuntu-Bernard kernel: [ 1854.101144] usb 1-2.1: USB disconnect, address 4


Detailled Camera info
lsusb -v

Bus 001 Device 007: ID 04a9:31e4 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          0x31e4 
  bcdDevice            0.02
  iManufacturer           1 Canon Inc.
  iProduct                2 Canon Digital Camera
  iSerial                 3 E2F5E9B80A584FFDA901B46ECBC87410
  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     0x0040  1x 64 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     0x0040  1x 64 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              32
Device Qualifier (for other device speed):
  bLength                10
  bDescriptorType         6
  bcdUSB               2.00
  bDeviceClass            0 (Defined at Interface level)
  bDeviceSubClass         0 
  bDeviceProtocol         0 
  bMaxPacketSize0        64
  bNumConfigurations      1
Device Status:     0x0001
  Self Powered