I need a new pair of binoculars.

[Sybarite]

Sybarite; ignore the mocking smart-alec responses.

I take issue with the final paragraph of your quoted post: "In truth though on a boat you usually do not need the 'see in the dark' quality of optics you need in a dark wood at last light." As I posted earlier in this thread, such conditions are exactly when I most value my 7x50 binoculars, When I am approaching my area of Italian lagoons at dusk with their myriad of channels marked by marker posts that can be quite invisible to the naked eye in low light, but with those binoculars I can clearly see them. No doubt my ageing exit pupil diameter cannot match the available 7mm worth of light supplied but it sure works for me.

My take on that is that he is not saying that you don't need the light grabbing qualities on a boat; I believe he is saying that you need them even more in a forest.

What I would prefer is a night sight of some kind.

 

[Sybarite]

Using the word "product" started my confusion; should have been "result". The calculation is really 50/7=7.1.

Then the misuse of "astigmatism"; from wikipedia: So nothing to do with pupil diameter. So what do we believe?

Mike.

Wiki : ".... at the peak age of 15, the dark-adapted pupil can vary from 4 mm to 9 mm with different individuals. After 25 years of age the average pupil size decreases, though not at a steady rate"

Agreed that astigmatism is not perhaps the best word as presbyopia produces similar effects.