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Message: <blockquote data-quote="Overread" data-source="post: 1793414" data-attributes="member: 68571">I suspect its because as you enter the macro distances the amount of motion needed for handshake reduces significantly and thus the IS has to do more work to keep the shot from being affected. The same is true of going ultra long - a 100mm lens with IS has to do far less work to minimies shake than on a 600mm lens. It's part of the reason why canon and nikon use in lens IS rather than incamera - because of the amount of different stengths needed for different lenses.I don't know if this affects IS at all, though its certainly a factor that affects AF and focusing in general. The loss of light when focusing at macro distances however is pretty much standard for all modern macro lenses and is part of how they achive such a close focus. Canon camera bodies don't report this loss of aperture so we can shoot wide open at f2.8 whilst nikon camera bodies do report this effective aperture loss and can't shoot at f2.8. Even though both lenses and camera bodies will deliver the exact same image (Beacuse the aperture blades themselves have not moved - the lens is still wide open, but its lost light internally). This of course leads to quite a few very confused nikon shooters in the world <img src="data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7" class="smilie smilie--sprite smilie--sprite2" alt=";)" title="Wink    ;)" loading="lazy" data-shortname=";)" /></blockquote>

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