NI Vision - Buying a webcam to make some measurements

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Pidgeon
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NI Vision - Buying a webcam to make some measurements

Сообщение Pidgeon »

Hello again, I start a new topic in the hope of solving the problem reported in my previous thread.

I need to buy a good webcam to make some measurements at home, for example to find broken parts, to measure diameters of rings, and so on (I've to do a LabVIEW exam about this kind of things).

I've found two interesting products.

http://www.trust.com/products/product.a ... rtnr=17342

http://www.microsoft.com/hardware/en-gb ... /H5D-00003

Trust:
- There seems to be a rotatory control to manually adjust focus
- 1280x1024 (Hardware)
- Unknown performance with low light
- 17 €

Microsoft:
- Autofocus
- 1280x720 (Hardware)
- Good performance with low light
- 55 €

Here is a video of the Microsoft webcam in action:

You can notice the good amount of detail it can retrieve with close objects.

I could buy the Microsoft webcam but my concern is autofocus. I've learnt that, after a calibration, the following conditions must be the same:
- Inclination of the plane on which the object resides
- Light
- Lens focus
So, with autofocus calibration wouldn't make any sense?

I've read that by using Microsoft software, you could manually set focus.

Anyway, my question is: would it be possibile to manually set the webcam focus in LabVIEW, for example though a slider control?
And, would you suggest me to buy the Microsoft webcam?

Thank you!
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mzu2006

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Re: NI Vision - Buying a webcam to make some measurements

Сообщение mzu2006 »

Any Directshow compliant webcam should be controllable by IMAQdx. You should be able to get an image. As about access to the controls, you might need to use an activeX interface that should come with a camera. LabVIEW provides very nice way to access automation (activex) objects. I have previous model of this microsoft webcam, so if you write some diagnostics software I might be able to run it for you at my place.
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