====== Camera & Lighting-System ======

===== Choose a Lense =====
  * http://www.scorpionvision.co.uk/industrial-camera-optics-blog/new-near-and-far-field-m12-lenses, https://scorpionvision.worldsecuresystems.com/Catalog/Machine-Vision-Lens/m12-lenses/near-field-far-field-m12-lenses/s-mount-8mm-macro-lens
  * {{ :maschine:pickandplace:lens_and_sensor_compatibility_by_scorpionvision.pdf |}} {{ :maschine:pickandplace:m12lenswhitepaper.pdf |}}
  * https://www.ptgrey.com/tan/10694
  * http://www.vision-doctor.com/en/optical-basics/mod-and-close-up-rings.html
  * Check: MOD minimum object distance? for which chip sensor size is the lense designed?

==== Bottom Camera ====
^ Lens  ^ Working Distance (Focus Layer to Camera PCB top)  ^ FOV            ^ Pixel/mm  ^ Images                                                       ^
| 6mm   | 66.5mm                                            | 20mm x 16 mm   | 59        | {{:maschine:pickandplace:fov_lens6mm_dist66.5mm.png?140}}    |
| 12mm  | 115.5mm                                           | ~20mm x 16 mm  | 48        | {{:maschine:pickandplace:fov_lens12mm_dist115.5mm.png?140}}  |
===== Downcam-Lighting =====
^ Images/Files                                                                                              ^ Type                                        ^ Description                                                                      ^ Evaluation                                                                                                                                                      ^ Snapshots                                                               ^
| {{maschine:pickandplace:head_light_diffusor.png?200}}                                                     | kind of direct light with diffusor printed  | Inserted 2 led strips shining through the ABS plastic.                           | Most default pipelines work with this lighting setup. Glossy finishes (HASL/white silkscreen) won't work well (mirror effect).                                  |                                                                         |
| {{:maschine:pickandplace:20170918_212846_hdr.jpg?200}} {{:maschine:pickandplace:lighting-setup.jpg?200}}  | direct polarized                            | linear polarizing filters (0° in front of led strips, 90° as cap before camera)  | no glare, perfect, but the metal parts are do dark and don't contrast other pcb colors any more                                                                 | {{:maschine:pickandplace:comparison_polarized_vs_unpolarized.jpg?400}}  |
| {{:maschine:pickandplace:dome-setup.jpg?200}}                                                             | tunnel dome v1                              | tunnel dome diffuses the light from led stripes                                  | no glare on pcbs. on feeders a little glare, but okay. in the center the camera will be mirrored in pads (if they are glossy), fiducials are good to recognize  | {{:maschine:pickandplace:dome-comparison.jpg?400}}                      |
| {{:maschine:pickandplace:dome_v2-setup.jpg?200}} {{:maschine:pickandplace:20170919_211256_hdr.jpg?200}}   | tunnel dome v2                              | tunnel dome diffuses the light from led stripes                                  | like v1 but wider to have a larger illuminated area                                                                                                             | {{:maschine:pickandplace:dome_v2_comparison.jpg?400}}                   |
|                                                                                                           | ringlight with diffusor                     | tested but results were too bad (glare, leds mirror on pcb)                      |                                                                                                                                                                 |                                                                         |



==== Links for further reading ====
  * https://groups.google.com/forum/#!topic/openpnp/7yUivDAALIg
  * http://www.ni.com/white-paper/6901/en/
  * http://www.cognex.com/ExploreLearn/UsefulTools/LightingAdvisor/?langtype=1033