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Is image shake related to field of view? (1 Viewer)


Sorry if this is a naive question - I'm curious if there is a relationship between field of view and image shake.

Does the perceived image shake reduce on binoculars with higher field of view if the magnification remains the same?

Assume we are comparing an 8x42 and 10x42 binoculars which have the same FOV of say 350' each. In this case, the image that is being captured is exactly the same although the latter is more magnified. So, if the same amount of information is being sent to the brain, would the 10x still feel more shaky compared to the 8x? If so, why?


Well-known member

this is actually a very interesting question. In this hypothetical case the true field of view is supposed to be 350 [email protected] or 6.7 deg (divide by 52.5) for both an 8x and a 10x pair.

In case of the 8x pair this results into roughly 53 deg apparent field of view (which will feel a bit constricted for most but not fully tunnel vision) and in case of the 10x pair this means around 67 deg afov - a nice wide angle view.

My suspicion would be that the brain tolerates a certain amount of movement of an image inside the apparent field of view and since the the apparent field is larger in the 10x pair, the same actual movement of the instrument by say 0.1 deg will translate into a larger movement of the image inside the afov with a higher magnification pair...

But I probably should try to read up on this tonight...



Well-known member
I think that the shake is more in the 10x than the 8x, as the central sharp vision is very small. About 2 degrees at most. And that is AFOV not real field.
It is I think the central sharp vision that sees the shake not the peripheral vision.



Well-known member
I don't think the size of the field stop has much influence on the perceived shake.
As magnification is angular magnification, 1° of shake in the 8x binocular would be perceived as 8° and as 10° in the 10x binocular.
A Swarovski NL is no remedy for DTs!


PS:- Sorry, Binastro; we overlapped.
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