A couple of months ago I spent a bit of time working on a camera based system for calibrating the position of a syringe needle in a LinuxCNC controlled "bioprinter". I found a couple of USB microscopes I had on hand to work reasonably well. The depth of field was quite adequate for needles, but milling cutters would generally be larger.
Are you planning on using crosshairs and "eyeballing" to determine your cutter length/diameter, or are you intending to automate the process? If you want automated measurement, you could look into subpixel measurement techiques. With subpixel measurement, you don't really want super-sharp focus anyway. You also would likely want multiple photos over a small range of distances from the camera, which allows you to do some averaging of your computed dimensions. -- Ralph ________________________________________ From: Russell Brown [[email protected]] Sent: Thursday, November 07, 2013 3:15 AM To: [email protected] Subject: [Emc-users] USB Camera for edge finder? I've been playing around with camview and a little 10mm endoscope type USB camera to see if I could rig such a thing up as an edge finder permanently mounted my mill's head. That's OK but you have to get very very close to the workpiece for even a half decent resolution which doesn't work when there's a collett holder and tool in the spindle (part of the reason for doing this is to avoid chucking the edge finder so I don't want a spindle type camera). I also tried a USB 'microscope' but the depth of field is very small again you have to get pretty close and twiddle with the focus to get a useful resolution. Has anyone found a USB camera with both a high magnification and a decent depth of field? (I've a feeling that these are mutually exclusive) or even one that can focus at a high resolution from a workable (~200mm?) distance? TIA -- Regards, Russell -------------------------------------------------------------------- | Russell Brown | MAIL: [email protected] PHONE: 01780 471800 | | Lady Lodge Systems | WWW Work: http://www.lls.com | | Peterborough, England | WWW Play: http://www.ruffle.me.uk | -------------------------------------------------------------------- ------------------------------------------------------------------------------ November Webinars for C, C++, Fortran Developers Accelerate application performance with scalable programming models. Explore techniques for threading, error checking, porting, and tuning. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60136231&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ November Webinars for C, C++, Fortran Developers Accelerate application performance with scalable programming models. Explore techniques for threading, error checking, porting, and tuning. Get the most from the latest Intel processors and coprocessors. See abstracts and register http://pubads.g.doubleclick.net/gampad/clk?id=60136231&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
