• In the below my starting point is how we experience (target) things with our eyes (this is contrary to normal practice in stereo world, but I just find my eyes too important). So even the eye diameter is playing a role, but don't despair it is canceled out further in the process;-).
  So bear with me, even thought it start with the human experience, I will come back to the technical stereo base.
  
• I want to make get a stereo pair that is experienced (targeted) like a real scene that has an farthest object as infinite (~6 [km]) and a nearest object of a certain distance.
  
• Parallax angle can vary considerable say between 1° and 4°:
  
  • a parallax angle smaller then 1° (or LAOFD), gives a flatish 3D image
  • a parallax angle larger then 4° (or HAOFD), gives a quite uncomfortable stereo view (more chance on eye strain).
  • A general accepted comfortable parallax (or OOFD) is around 1.88° (=2*atan (65.5/2000/2)) due to a nearest object of 2 meters and a farthest object at infinity. 
• From that assumption I want to determine how to make the stereo pair with a photo camera (in the below by default a digital camera).
I use parallel viewing method as the default in the below, in the below calculations other stereo viewing methods can be set.

• I am aware of the Stereo Calc of Takashi Sekitani (this one assumes that Fc << focused distance), the spreadsheets of Mike Davis (this one assumes an MOFD= Fc/30) and the JavaScript of Gerhard Herbig.. These will gave comparable results as below calculations, when determining the stereo base based on MOFD.
• Some guidelines and formulas can be seen here.
• I have the stereophographic guidelines also as functions (Add-in) for Excel available, so one can build one's own application around this Excel Add-in. If you want more information, let me know (remove underscore in presented e-mail address)!

• Parallax angle target is: p_exp = 2*atan(eyeseparation/2/nearestobject_exp) (in this simplified formula: farthestobject_exp = infinite)
  Using:eyeseparation = [mm]
  nearestobject_exp = [m] (This is for targeted experience, so no relation with the actual objects in the scene)
  farthestobject_exp = [m] (This is for targeted experience, so no relation with the actual objects in the scene)
  p_exp = °
• MORD (Maximum On Retina Deviation) becomes: MORD = tan(p_exp)*eyediameterinair
  Using: p_exp = °
  eyediameterinair = [mm] (diameter eye in water is 22.22 [mm] and in air this seems smaller due to reflection index: 1.333)
  MORD = [mm] (see also the graph on this page).
• MOPD (Maximum On Picture Deviation) is: MOPD = MORD*distancepicture/eyediameterinair
  Using: MORD = [mm]
  distancepicture (or F_v) = [mm] (distance to picture or focal length viewer when using slideviewer/stereoscope)
  eyediameterinair = [mm]
  MOPD = [mm]
  
• MOFD (Maximum On Film Deviation) becomes: MOFD = MOPD*filmwidth/picturewidth
  Using: MOPD = [mm]
  picturewidth = [mm] (width of a single picture, not the pair: max. width when using parallel viewing is eyeseparation: [mm])
  filmwidth = [mm]
  MOFD = [mm]
  
• Stereo base (b0) is: b0 = MOFD*(nearestobject_act/F_c-1/2) (in this simplified formula: farthestobject_act = infinite: case 2 of Bercovitz)
  Using: MOFD = [mm]
  nearestobject_act = [m]
  farthestobject_act = [m]
  F_c = [mm]
  b0 = [mm]
  diaphragm (f#) >= [-]
  focus distance = [m]
  non overlap on film (no convergence) = [%]
  convergence distance >= [m]
  

• 60 mm stereo base
• 220 mm stereo base
  

• 60 mm stereo base
• 240 mm stereo base

Change stereo viewing applet/plugin properties

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