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Andre Labonte wrote:
^^^ This clearly shows you do not understand optical design. As light goes through a lens, it goes through a number of optical elements, some of which may be quite small, even for an f/2.8 lens. In fact, for a given required image circle and focal length, the rear elements are all about the same size regardless of the maximum aperature of the lens ... you'll notice that in most VR lenses, the VR elements tend to be toward the back of the lense where elements are smaller.
VR makes little difference in the size of a lens. A few examples:
Nikon 18-55VR is only 0.2 inches longer and 2oz heavier than the 18-55 without VR
Canon 17-55 f/2.8 with IS is the same size as the Nikon 17-55 without VR but is in fact lighter!!!!!
That pretty well torpedos your whole explenation. Dude, stop talking, the more you do the dummer you look....Show more →
Please do not make me laugh at what you just put out.
[Edit]
I didn't want to add this in till you replied so as to show how much you know.
Using 2 DX lenses with image circle not even optimised for the F-mount can have lots of excess space yet to be utilise, but using FX lenses will be very different. And using a pair of variable aperture lenses with f3.5-5.6 even make it more laughable, isn't f3.5-5.6 already showing light loss when zoom compare to fixed f2.8 or f4 lenses? With aperture starting at f3.5-5.6 most shots will look exceptable to good anyway, but it will be very different if it is at f1.4 or f2.8 corner to corner.
[End Edit]
If you are just talking about the rear element everyone knew it is about the same size base on the image circle, but all others are base on the focal length and the field of coverage starting from the front element. When one squeeze in a couple of elements between 2 groups of elements, it actually increases the focal length and decreases the field coverage which means some kind of compensation are needed. Not going into details to make you smarter.
For the example you pointed out about the Nikon 18-55 VR and non-VR, isn't 0.2 inches and 2 oz an increase? How about the diameter and most importantly of all the final image quality taking into account that the later always has some kind of improvement to the previous design?
For Canon 17-55 f2.8 IS being lighter than the Nikon 17-55 w/o VR , they cannot be compare to each other because they are of different design and using different materials and elements, just like an AI-S 50mm f1.4 and AF-S 50mm f1.4G with a motor in it is still lighter. There are these materials we all call plastic, polycarbonate, metal, glass and so on. There are so much things that you do not know about and yet you are trying to show how well informed you are.
Finally calling people Dude and dummer doesn't make you smarter.
I think I have enough of these rude communication from you.
END OF TRANSMISSION.
Edited on Oct 05, 2012 at 09:36 AM · View previous versions
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