DIY Laser levelling using webcam and laser level

[devmonkey]

Thank Joe. I understand now. I think my confusion came from your first reply to me where you said "... so you can either zero both rails to this plane..."


Have you seen this project. Looks like it shares some similarities but for a very different result.

https://hackaday.io/project/21933-op...solution-laser

Dave.

I hadn't seen that particular project, but yes they are using a prism to project a line, However note the accuracy of the prism, it is ~1 arcminute (290um over 1m), this is fairly standard and although readily available unfortunately useless for our purposes, we need <1 arcsecond which are a rather more expensive and difficult to get.