## industry cameras
###############################
5gige and 10gige more expensive + might get bandwidthproblems with 6cams? + 10gige need externalframegrabber
usb2 - too old

> usb3
    - 4.5m cable
    + usb3 interface card with 4 cams connected
> gige
    + 100m cable
    hi res (20MP) and low fps, or
    low res (2MP) and high fps
    bandwith average. between usb2 and 3
    -> can i reduce the fps manually?

multiple cams:
    star-network using an ethernet switch (bandwidth will be divided), or
    a point-to-point network using an interface card with multiple GigE inputs.

what interface gige card to use?
    > needs to support PoE
    > ETH from PC provides PoE? if no, then interface card

## Heating:
> cable:
    cat6a is better than cat6 or 5e
    dont bundle multiple cables together

## lens
420nm and 720nm and 800nm-1300nm IR
IR corrected -> can be used for N IR

problem: spheric abberation = rays farther from center are refracted to different focal point
    > most @ max aperture (f1.8)
problem: chromatic aberration = different colors (wavelentgths) have different focal lengths (sa. ~prisma)
    > color finging
    > longitudinal and lateral CA

solutions:
    > achromate = multi-lenses (doublet, triplet).
        color correction (blue+red)
    > aspheric
        different form of lense (not spheric :)
    > aspheric achromate
        susceptible to scratch.
        good quality
-> ir-corrected doublet/triplet

"fast aperture" = max aperture -> eg f1.8 needs to be quick to close all the way
DOF
-> is it possible to use a non-IR gigE cam with a IR-corrected lense, for nightvision?
-> angle + distance
    fixed or zoom lens

-> cant get color img _and_ IR img at the same time
    -> opt for IR, because it works with light and without

thermal >= nightvision
see through fog/grass?  ---


450 2mp cam
600 5mp cam

Lense:
calculate fixed focal length (fest brennweite)
8mm >>
6mm >> 225oi
5mm >> 60cm

<900nm QE           ringlichter >> NIR.

calculation:
> 50 cm diameter -> 500mm
> 2.4 MP (1936x1216) -> 1216 pix per line
1216 / 500 = 2.4 px/mm
small insect = 4mm -> 8px -> 8*8 = 64px...


-> can i use SWIR for VS as well? yes, but they are unaffordably expensive
-> SWIR for RaspPi? or usb3? cheaper?

## DOF - Schärfentiefe - Tiefenschärfe
#############################################################
https://photographylife.com/what-is-depth-of-field
app: simple DOF calculator
https://www.edmundoptics.com/c/achromatic-lenses/652/#

> more DOF on
    * smaller focal length
    * lower aperture eg f16 > landscape

> less DOF
    * high aperture eg f1.8
    * larger focal length -> zoom 150mm
    > BOKEH. nice creamy background
    > macro, landscape with FG-POI

> f5.6 sharpest + best middle ground

## crop factor // sensorsize
    > equivalent focal length
        eg. olympus 2x
        8mm > 16mm - narrower
        100mm > 200mm -more zoom (fake crop zoom)

    > calc equiv. focal length:
        https://www.translatorscafe.com/unit-converter/en-US/calculator/lens-efl/

    > smaller sensor
        = more crop and more "zoom" (narrower field of view, less DOF)
        = less light, dynamic range, pixelsize
        = less pixels (normally)

    > bigger sensor
        = less crop, wider field of view -> can crop manually (but more DOF)

##build myself... IoT / embedded camera
  raspberryPi + CAM
    > 15€ possible?
    > https://www.raspberrypi.com/products/raspberry-pi-zero-2-w/
  MIPI CSI2 - interface -> all Pis have interface
  >> datarates?
  >> IR / lowlight compatible?
  >> howto make rugged?

  nvidia jetson nano?
  https://www.nvidia.com/de-de/autonomous-machines/embedded-systems/jetson-nano/

csi(2) - pi: camera serial interface
dsi(2) - pi: display serial interface
csi/dsi -> max len 25cm!
    --> via FPD-Link III up to 15m
    --> GSML2 ?
###############################
hub/repeater > just cp data to all connected
switch       >
router       >
codemeter
GenICamBrowser
###############################



## How-To Stream?

    SS = Streaming Server

    GT 1920:
        read stream specs.
        search VIMBA ... IP-based.

    ndi-python
        wrapper for NDI-SDK
    ffmpeg as RTMP-SS
    nginx
        nginx-rtmp-module
        linux SS
    openCV
        VideoCapture(  protocol://host:port/script_name?script_params|auth )
    Gstreamer
        QT
        Vimba plugin?

    obs-studio/jammy 27.2.3+dfsg1-1 amd64
        recorder and streamer for live video content
        can use NDI?