longkangman said:
Still the RSM don't seems to answer the question precisely. :think: :dunno:
400mm on a 1.6 or 1.5 crop already more than 500mm. :lovegrin:
300mm on a 2.0 crop is 600mm.
Do hope the RSM read this. :devil: :lovegrin:
Hi
Ya I was in tune with the above before, but the real truth
is a 400 mm on a 1.6 crop is not more than 500mm. Optically
there is no advantage. You only view the photo 'as though'
you are using 500mm. Its all marketing talk.
A D2X with on hi speed crop mode on will make a 400MM lens
look as though you are looking via an 800 mm because
the camera throws away most of the outer parts of the
photo captured by the sensor.
If you put a 800 MM lens on any camera, you will have a much
narrower view compared to a 400MM and compared to a 50MM
Since the lens I have are all full frame lens, puttting it on a 20D
or a D2X means that the DX size sensor will only record the inner
parts of what the lens is providing. The rest of the light channelled by
the lens 'falls off' the Cmos/CCD capture device, onto inert parts of
the camera shutter chamber.
So if you buy a canon 5D , take a photo with a 400MM then you
crop it 1.6 its size, it will be almost the same as a 20D took the
same photo with a 400MM.
The only diff is that the 20D May resolve more detail because the pixels
on the CMOS sensor are packed more closely as compared to a full frame sensor.
Anyway, putting on a TC is bad because if you dont have a F2.8 400MM
the focus will SLOW down and you may lose your shots. I also don't
know if the viewing area is suitable for aerial photos because the Sun
may not be in your favor.
Question: Is it good to bring along that 2 step ladder so you are
above people's head and you don't have to fight/jostle for space?
Allan