No. A 300mm lens is NOT a 450mm lens. The sensor is smaller than a 35mm,
so the focal length angle of view is different. It is a crop, not a
multiplier. 300mm is 300mm. An 80mm lens on a 6x6 negative has the angle of
view of a 50mm lens on a 35mm negative. This does not make an 80mm lens a
50mm lens. It is STILL an 80mm lens. This doesn't have a thing to do you
your question, but this misinformation about multipliers that some people
spread around without an ounce of thought should have been laid to rest long
ago.
As for blurry images, before drawing any conclusions or going to a lot of
effort, just turn off the autofocus and focus manually. Coming from manual
focus film cameras, I have noticed that folks who were introduced to cameras
with auto-eveything seem to have a reluctance to turn stuff off. That
automation works wonderfully in MOST situations. Your brain works great in
almost all of them. I have found that if you are not careful, the camera is
looking at something you aren't, and foucsing on that.
"BobS" <spam_at_eliminator.com> wrote in message
news:0q2Zc.50199$Kt5.34199_at_twister.nyroc.rr.com...
> If you're zoomed all the way out, that lens is effectively a 450mm tele
when
> it's on the D70. As I recall, the D70 has the same size sensor as my
Pentax
> *ist and means you have a 1.5x multiplier factor.
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