Is there a way to determine if a IMAQdx camera session is still valid or not ?

[zou]

If it's valid, IMAQdx Open Camera.vi will return an error.

If it's not valid, IMAQdx Close Camera.vi will return an error.  And IMAQdx Close Camera.vi is very slow when the camera session is not valid.

[BlueCheese]

What do you mean by "not valid"? Do you mean already closed or the camera has been removed but your session is still open?

[zou · Accepted solution]

I mean IMAQdx Open Camera.vi haven't been called yet, or IMAQdx Close Camera.vi has been called.

Although there is no property node for that purpose, other properties, such as camera vendor name, are acceptable workarounds.

[BlueCheese · Accepted solution]

For that scenario, the "Not a refnum" primitive should work, I believe.

[zou]

Interesting.

The camera session is "cam0" when prob before and after call IMAQdx Open Camera.vi.

No change, not empty.

That deceaves me.