I don’t have a printer in my shop. Is there a way to print the pattern at home to use? I am adding a camera to my 100w co2.I have been looking for it but have not found anything.
Sure. You can download it from the docs page. Or you can even laser it to a piece of wood.
Can you tell me where it is. I have been looking for it. I am not the sharpest knife in the draw sometimes.
Start here…
Sure! Copy the Lightburn file to a USB memory stick and take it home with you.
Direct link to the relevant section of the documentation:
Thank you so much.
For the lens calibration you can use an iPad or similar tablet. The alignment step does require you to etch a piece of material.
easiest i found was to get white posterboard and use the laser itself to raster the April9 test pattern array scaled at approximately 1/3 the x and 1/3 the y of the bed size, and put 8 more pieces of white posterboard over the rest of it. or, any convenient shapes that allow you to cover the rest of the bed as you reposition the april9 across it.
this was particularly important for my 1.6mx1.0m bed. the standard 8-1/2" x 11" printer sheet size is too small and i realized just how few cheap options you have other than a printer. pay to put it on s large format printer, which is also hard to keep really flat, and if mailed is going to come in a tube.
there wasn’t any drawback to rastering it big onto posterboard, though. walmart sells the product flat and it’s easy to keep flat
my experience was it didn’t seem that the honeycomb texture being picked up by the camera that was the main problem. rather, the very black blackness of the honeycomb was like 90% of the camera’s field of view so the camera Automatic Gain Control turned the gain way up to bring the majority of the FOV- the honeycomb- into the right dynamic range. which blinded the camera where the april9 was. lowering the brightness didn’t fit it very well, the image quality problem was in the hardware. changing the lighting in the room affected both regions so no real fix there. changing to darker posterboard didn’t work well either. the laser rasters the posterboard into a medium brown shade regardless of the original surface color, so starting from a dark blue gave poor contrast
so, being posterboard wasn’t the actual source of the problem. but it made it easy to get extra and cover all the honeycomb and therefore bias the AGC correctly
the AGC did continue to be a problem in actual use. most of the time, a lot of the FOV sees black honeycomb and the gain goes higher than needed and washes out light colored plywood or whatever.
awhile back i was trying to get a 12MP HDR raspberry pi camera to do this- not so much because i needed more resolution, but the rpi gets low level access to the hardware and software could be used to identify honeycomb and exclude it from weighing in for the purpose of AGC bias. or, being HDR, that opens up the idea of taking multiple shots across the AGC range and combining the image data into an HDR image.
also, the 1.6m x 1.0m frame made for too long of a USB cable run, and it didn’t play well with most USB extenders. rpi could just have power wires and be a wifi or Ethernet camera with no cable limits
that one i couldn’t put a varifocal lens on it, the silicon imager area was physically too big. but a fixed anamorphic lens looked like a pretty close fit for it.