[ATM] Exit pulil and brightnees

[Marinus van der Lugt]

For point objects against a black background, the brightness is  
reduced. This equals a reduction in contrast and hence in detectability.

However for extended objects all the brightness is reduced by the same  
factor. There is no chance in contrast and hence no difference in  
detectability.

Rien.


On Mar 1, 2008, at 3:52, George Nikolidakis wrote:

> Hello everyone ..
>
> It is known that the diameter of the eye pupil is reduced by the age.
>
> I found some references professing that means to lose in object  
> brightness,
>
> looking trough an eyepiece with greater exit pupil than your eyes.
>
> Or, to put it another way, a younger person looking from the same  
> eyepiece
>
> will see the object Brighter.
> So in my view it seems to me that the older person simply lose the  
> edges of
> the field
>
> and not in object brightness.
>
> But what view is finally right ?
>
> George Nikolidakis
>
>
>
>
>
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