change of resolution with logitech 920 USB camera

[labmaster]

I checked the available resolutions and framerates in MAX, and I get an error when programmatically changing to the desired resolution.

After reviewing several posts, the result from the LabVIEW example "Getting Started with Attributes.vi" using IMAQdx Enumerate Attributes indicates that "AcquisitionAttributes::Height" is not writable.

I suspect this is an issue with the camera (Logitech C920). Is that correct?

If so, how can I determine if programmatic resolution changes are possible before purchasing another camera?

Additionally, in MAX, I can set and save the resolution. How is this change applied?

labmaster.

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The video mode appears as writable, but even when trying to change the video mode with the code below, it doesn't work. No error occurs at the property node, but right after passing through Configure Grab.vi, I get -2147220969, an undefined error, which makes it even more difficult.

[aeastet]

The spec says that it should be able to change to these resolutions: 

Image Capture (16:9 W)

2.0 MP, 3 MP*, 6 MP*, 15 MP*

If you use the vi called "IMAQdx Enumerate Video Modes.vi" you will be able to see the available video modes in the camera. I use this to populate a ring and then I can change the ring value to change the camera settings. 

[aeastet]

You will also need to end the session of the current camera set up the camera again start the session and then set the video mode again.

[Jacobson]

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@labmaster wrote:

If so, how can I determine if programmatic resolution changes are possible before purchasing another camera?

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If you want to use NI's IMAQ drivers it's probably best to pick a camera that follows one of the specific standard supported by the driver like USB3 Vision or GigE Vision.

I may be mis-remembering the details but I thought USB 2.0 cameras would work through DirectShow and, for some reason, not all the properties are always exposed through that API.

[aeastet]

I have integrated many different USB cameras into my camera software. I believe that this was one of the cameras I have used. You should be able to do all of what you want to do. Every USB camera that I have plugged into my software works great. I do not think you need to go to an expensive camera like gig E unless you really want to. Not sure about what you are using it for but I can tell you that this camera that you are asking about can be controlled using the IMAQdx code. You will have to build the camera loop to do everything that you want.

[labmaster]

aeastet,

It was the same method you used.
Upon closer inspection after posting, I noticed that "unknown" was included among the possible modes, and I accidentally selected this mode, causing the error.
After filtering the possible modes and creating the ring, the issue was resolved.

labmaster.