My camera is 22CM distance to surface

My machine is 600X400MM laser,i want the distance of camera to surface is 22CM.I don’t want camera installed so high.But when i make camera alignment wizard,i can not get the capture.I make the camera higher,about 29CM,can get the capture.
Anyone know why?How i can get capture in lower distance about 22CM?
Thanks

You will need a very wide focal length:

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