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Originally Posted by Wolf_Rider
read mine...I added some as well.
keep on trying....
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Have you read my post and what you added? Do you realise they prove me right?
Quote:
Originally Posted by Wolf_Rider
*Edit
Lenses
A convex lens bends the light that goes through it toward a focal point. The light spreads out again past this focal point. Magnifying glasses are convex lenses. When you use one, the lens bends the light rays so that they come together and focus on the lens within your eye. The light then spreads out as the rays continue past the focal point, and they hit the retina of the eye. The spreading of the light makes the image viewed appear much larger than it really is because it causes the image to take up more space on the retina. Moving the magnifying glass closer or farther away from the eye will change how much the light is spread on the retina. The closer the magnifying glass is to the eye, the bigger the image will appear.
Read more: How Does Magnification Work? | eHow.com http://www.ehow.com/how-does_4947702...#ixzz1tF7id261 |
What is being described here is this - the magnifying glass bends light gathered all over its surface toward a point behind it in a cone. The closer you get to that lens, the bigger the image on your retina, and the more magnified the view.
Do you know another way of describing that? That's right! The amount of your retina taken up by the image determines apparent size!
Think back to what I wrote - it is ultimately the size of the image on your RETINA, not your actual angle of view, that determines apparent size. When nothing interferes with your angle of view, your eye does the focussing onto the retina, and thus your actual angle of view correlates with apparent size.
But if we place a lens - such as a magnifying glass, telescope, binoculars etc - in front of the eye, your ACTUAL ANGLE OF VIEW - ie, the view out from your face - is no longer important, because your eye's field of view has effectively been replaced (or supplemented really) by that of the lens! And depending on the lens, it may have a very wide or narrow angle of view.
The fundamental principle here however is the portion of an image that is being displayed on your retina. The more of an object fills your retina, the larger it will appear!
Quote:
Originally Posted by Wolf_Rider
No... lenses are... but that seems omitted from your addin to your previous post...
FoV (or as you'll interchange them now Angle of View) is the amount (the angle) the lens "sees"... magnification, via a series of lenses as with binoculars, brings that image closer (or further away if you look down the wrong end)
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Well it actually makes the image FROM the lens take up more of your retina. Its the image on the retina that is important.
Now you might say - well whats that got to do with fov? Why isnt it just bringing the image 'closer'. Well, first of all, its about the size of an image on the retina, not how 'close' it is. Thats why we talk about angular size.
For example, how big is the sun? Our brain knows its very big, but in reality, it appears no larger than the moon! Thats because the moon is much closer, and its angular size is similar!
If we didn't have extra information to determin which is bigger, we could be forgiven for thinking the sun was no bigger than the moon!
More importantly though, LENSES HAVE FOVS OF THEIR OWN, AND IT IS THIS FOV THAT IS IMPORTANT. In other words, the FOV OUT of the binoculars is given by the lenses in it, and this ultimately determines what portion of the world the binoculars focus on our retina. The smaller this slice of the world, the bigger individual objects appear on our retina - and thus the more they are MAGNIFIED.