Camera Overlay Issues

I seem to be having issues with the overlay being a long way of anything up to 20mm.
I have followed all the steps and seem to have it calibrated correctly but I am so far out
with any overlay that I am trying to repeat. I can set an offset in the camera window but the next time I do a overlay I have to reset the offset again.

Any help would be most grateful

Alan

I’m having a hard time parsing what you said - I assume you mean “a long way off of anything, up to 20mm” as in, as much as 20mm off?

For the second part, are you saying that the offset settings don’t stay, or you keep having to change them every time you make a new capture?

Things in general to check:

  • When you take a capture, the camera has to be in exactly the same location as it was when you did the alignment. If the camera moves, all the math goes out the window.

  • When you capture, the top of the material has to be at the same height as the top of the alignment card was - this would normally be at the focus point of the laser

What were your scores when you did the camera lens calibration? Can you show a picture of the resulting captured overlay, and the image from the camera view window? I assume you’ve watched the calibration walkthrough video?

HI Oz

Sorry about the wording.
yes I did mean as much as 20mm off.
Yes I had to change the offset on every new capture
camera is in the same place as the alignment
material set to same focus point as alignment card
All my scores were 0.6 or below.
Yes I have watched the video.
I will send a couple of photos later.

Alan

0.6 is pretty high - I’m able to get 0.1 to 0.2 quite consistently, so I would see if you can improve on that, and make sure when tagging the marker points that you try to be as accurate as possible. If you have a larger machine, run the marker pattern scaled up to fill more of your bed, as that helps improve the accuracy as well. On my 700x500 I ran it at 175% I think, maybe a little more.


Here’s the picture.
I did upscale to about 120 (this was the max I could go). I tried many times to get better results but these are the best I can get.
I have 600 x 400 machine and using one of you 160 degree cameras

Alan

I have no clue how you got that low of numbers. Lowest I got at any point was .43 rest were .8-.9. I tired every way possible to get better numbers.

It’s not magic, but there is some intuition to it. I focused the camera first (which is a fairly important step, but one I glossed over in the video) and held the card at the appropriate distance and angle - that’s it. The angle of the card and the distance will both affect the number - Do a few captures in a row changing the position and angle of the card slightly and get a feel for how it changes. Getting that low in the corners with a 160 degree camera is tricky, but the middle and sides isn’t hard.