The day I received my Canon 300mm f4L lens, the first thing I have done
was to run to Elizabeth Park Lake in Fremont to shoot some picture of
ducks and pelicans. Using 35mm Camera minimum shutter speed rule of thumb,
I set the shutter speed at 320 and kept on hand held shooting merrily.
After returning home I could not believe my eyes, at 1:1 magnification
the pictures looked very soft on monitor. I could not see any tell tale
camera shake signature but I could not count fibers on the duck feather
Close up details of the above image
Next day, before sending the lens back to service, I though why not give
it a try with higher shutter speed. It was night and no bird to shoot,
so I fitted a Canon EF25 extension tube after my 300mm tele to reduce
the minimum focussing distance and shoot the ear ring of my wife from
a distance of 5 feet. The picture was shot at full open aperture 4 with
built-in flash. Shutter speed was 200 (but this time very short duration
of flash acted like a high shutter speed) and hand held the lens. The
result was simple astounding. Now I can count each and every microscopic
velvety hair on the skin, see the reflected and refracted lights from
the tiny ear ring stone and all the folds on the skin. Now thatís what
I called sharpness.
This incident taught me the lesson that with D30, the minimum handheld
shutter speed for a non IS telephoto lens should be greater than inverse
of 1.6 times focal length of the lens. So for 300mm, it should be 1/500.
Otherwise, the pictures will be soft due to micro camera shake, which
may not be visible at small size print but it will be strong enough to
make this tack sharp lens a soft one.
Closeup details of the above image