what you want to do is to switch the camera option Projection from 'Perspective' to 'Orthographic'.
launch the camera toolbar
reading the camera toolbar right to left, the first button you find is a STOP sign button.
The next button is the 'Reset Camera and Scene Light'.
The next 2 buttons toggle between 'Perspective' (3rd from right) and 'Orthographic'.
Click on 'Orthographic'
You see the stem rods are now equally spaced regardless of the colour set.
I am attaching a screenshot in a few days, just exhausted uploads for 24h.
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