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Not as simple as that, when you look through a lense you do not focus on the lense itself, your eye will focus on the object that the lense is pointed at. As for the spot or circle That depends on what it is and where it is. If for example you have a coloured ring or spot on the front of the lense then the light from the target will hit the lense and the coloured ring. Light of the correct colour will pass through the ring and then be acted upon by the lense so the coloured ring will be same focus as the target because all the ring does is change the colour of light coming from the target.
As for the one focus distance, that is for light going through the lense and falling on a flat plane. The light coming through the scope goes to another lense in the eye.
Next there is the peep to consider some peeps are small enough to exhibit a 'Pin Hole lense' effect, so you effectively have two lenses in the system. And that is where my brain splutters to a stop so draw you own conclusions.
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I am not a grumpy old man, I am a cynical senior citizen
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