Spontaneous Disconnects

[smithn00]

My camera is a Canon T3.

BEOS version 3.1.3

Dell Inspiron 1501 laptop running XP.

 

This combination of software and camera works well on my HP Desktop.

 

On the laptop:

Software connects to the camera and recognizes a T3.

Click on "Start Capture" button for 1 sec exposure.  I can hear the mirror click up and down and download starts.  About 35 sec later the camera disconnects.  No image file is stored.

 

Ned Smith

 

N 34,53,38.13

W 85,28,17.10

Near Chattanooga, TN

 

 

[admin]

All disconnects are USB related and 99.9% of the time they are related to too many devices connected on the USB hub and that leaves relatively no bandwidth for the camera.  If the Canon SDK can't see the camera, even for 1 millisecond, it will disconnect.

 

How long is your cable?

Are you using a USB hub?

How many devices are connected to your USB hubs.

 

Regards,

[smithn00]

The cable is roughly 6 ft. long. It is plugged directly into the laptop.  The only other USB connection on the laptop is to my mount.

[admin]

Is the USB port speed 1.1, 2, or 3?

[smithn00]

Is the USB port speed 1.1, 2, or 3?

Not 3 for sure.  How can I find out?

[admin]

It's probably 2.0... unless you computer is very old... it which case it will be 1.1.

 

You need at least USB 2.0 otherwise, well, the camera will disconnect due to not enough available bandwidth on the USB bus.

 

If you have 2.0 USB ports and it still disconnect try another USB port on the computer... perhaps one from the other side of the laptop if you have some on opposite sides.

[smithn00]

My laptop has 4 USB ports. I have tried three of them. The forth is for the mount.

Should I conclude that I can't use BYE with this computer?

[astroman133]

Ned,

 

I tried to find out the detailed specs from the Dell web site, but they don't list models that old. I did find a web site that says that the 4 USB ports are 2.0, so that should not be your problem.

 

Has BYE ever worked with this PC?  It is very old (almost 10 years) and may be underpowered for what you are trying to do.

[admin]

My laptop has 4 USB ports. I have tried three of them. The forth is for the mount.

Should I conclude that I can't use BYE with this computer?

 

Maybe, but disconnects are hardware related, not software.  So you must have something else at play here.  It is hard to tell.

[astroman133]

I did not mean that the USB ports could not be the problem, only that they would not be causing a problem by being USB 1.1 ports.

[smithn00]

Ned,

 

I tried to find out the detailed specs from the Dell web site, but they don't list models that old. I did find a web site that says that the 4 USB ports are 2.0, so that should not be your problem.

 

Has BYE ever worked with this PC?  It is very old (almost 10 years) and may be underpowered for what you are trying to do.

This laptop (Dell Inspiron 1501) runs my portable 10" DOB that I use for public outreach.  I want to add more possible sights by using a DSLR.  Since it runs XP Geek Squad won't touch it and I don't have the knowledge to fix it myself, It may be time for a new (used) laptop.

[s3igell]

Ned, remember that the "slow speed" of Data being sent to any Mount (Dob or otherwise) is significantly much less than the "Burst of High Speed Data" which a DSLR will Send when an Image is Downloaded.

 

Perhaps a decent Alternative Test would be to Capture a number of Images with the EOS Utility App that came with your DSLR.  As long as you set a Duration of about the same length as your BYE Exposures, you should be approximating the same "Bursts of High Speed Data", and should see similar USB Disconnects.

Also, remember that you can do these Tests at any Time - just connect the Camera (and Lens Cap) to the Laptop using the same USB Cables as you would during your Astronomy Sessions...

[smithn00]

EOS utility responds the same way.

Frame and Focus works but downloading an image does not, in bothe EOS Utility and BYE.

 

This confirms, IMO, that the issue is hardware (or driver) related.

 

Since it appears to happen on download, I'm willing to bet the issue is USB bandwidth.

[s3igell]

Since it appears to happen on download, I'm willing to bet the issue is USB bandwidth.

That would seem a Good Bet.  But it could also be a Bad USB Cable.  It seems a Less Expensive option to try a New USB Cable (get one of good quality - not just the cheapest) before resigning to a New Laptop.  (After all, BYE is very Forgiving and rather Light on even an Old Laptop...)

[s3igell]

If not a Bad USB Cable or Port, perhaps there is a different Task that is running in the Background on you XP that is taking substantial CPU Time every time you start a Download.

 

To check this:

1) Bring up the TaskManager (right-click on the empty part of the Task Bar or Ctrl-Alt-Del; then select TaskManager)

2) Select "Processes" Tab

3) Sort by "CPU (descending)" by clicking on "CPU" in the header twice

4) Watch the top several Processes as you work through attempts to capture Images in BYE

 

Does anything stick out??

[smithn00]

Total Usage never got over 25%.  I'll try another cable later.