On 9/10/2012 5:07 p.m., Trevor wrote:
"Rich" wrote in message
...
Why produce a top flight APS camera? Why object to the top camera being a
D90 "upgrade" with a FF sensor and not a D300 upgrade with an APS sensor?
Now that APS has hit 24 megapixels, it has to be considered it offers the
best option for wildlife photography, outside of the D800, but more
importantly, it does give lenses greater "reach" so somone can shoot
wildlife with a relatively portable 300mm lens versus a much larger and
heavier and much more expensive 400mm lens.

Actually you just crop that D800 36Mp image with a shorter lens, back to
24Mp, and there is no practical difference, except you can still get 36Mp
wide angle shots when you want. Or reduce noise by averaging back to 24Mp
when you want that.
Best of both worlds!


Linear resolution comparison of a 24mp APS and a 300mm lens and the D800
36mp and a 400mm lens gives APS about a 8% resolution advantage, so for
all
purposes, they offer the same resolution. However weight savings of the
camera-lens combos gives the APS a distinct advantage.

Not much if you compare as above. Only the body weight is higher, and some
of that is materials used, not just sensor size.


In fact, it may be possible that true resolution comparisons would show
even greater advantages due to higher stability offered by the lighter
combination, either on tripod/monopod or off. It would require testing to
determine that.

Extra weight reduces the effect of vibration, not less weight, especially on
a tripod.


I wish they'd release a 40mp APS sensor for low ISO, high resolution work.

You won't have to wait long I bet, but probably far longer for low weight
APS lenses with resolution that can actually use it. I don't see too many at
the moment.

Trevor.


It's not quite that easy.
These are actual relative VF sizes, with CAM3500 AF point placement,
D800 / D300:
http://i45.tinypic.com/549e8n.png
(users of Fx models often make the mistake of comparing typical APS-c
viewfinders in cameras they've handled with Fx models, which are about
the size of the "dx crop" brackets shown in the D800 VF. Yes - the Fx
viewfinder is larger, but not /that/ much larger than the D300. The Fx
model in Dx crop mode is about the same size view as entry level APS-c
cameras). The VF in D300 (and D7000 models) is actually pretty damned good.

There's also the probability that as the D300/s could do 6/7/8 fps, then
the hypothetical "D400" would at least match that, and probably an
updated "D400" would allow for a much larger (frames) buffer than the
D800. Sony manage to get extremely high frame rates with their sensor
in the a77, the data readout and image processing speed is about 50%
higher than the D800 (or D4).

As for cheap lightweight telephotos, I expect even the "cheap 'n
cheerful" Nikkor 55-200 VR would be fine with 24mp APS-c sensor. OK -
you're not likely to want to shoot sport with it, but the resolution is
extremely good.

The "D400" would probably cost $1200 less than the D800.

Finally, unless you're prepared to fork out big $$$ and carry the weight
of superb lenses like the Nikkor 14-24, then even at the wide-angle end,
the "improvement" gained by lenses like the Nikkor 16-35 VR over some of
the better APS-c WA zooms is marginal - especially for edge performance.

The D7000 sensor shouldn't be used as an expectation of what to expect
from a new APS-c sensor. The D4, D800, and D600, when used in Dx crop
mode, all exceed the D7000 performance. (BTW the D800 in DX crop mode
is about 16mp, not 24mp).