Not much. If it is meaningful to relate basic image quality to camera size, then one should also include camera weight which, for some of us who go trekking, is more important than camera volume.
However, the choice of camera is likely to be dominated by the range, quality and cost of available lenses, as well as the weight of such lenses.
Weight and size are the two qualities about which there can be little dispute. I've never seen a thread on this site arguing about the claimed weight and size of any piece of photographic equipment. Weight and size are the easiest specifications to appreciate and understand.
In a first order the Camera Dimensions may correspond to the Weight. But then, at same Camera Dimensions a higher Weight can speak for a more solidly built body. So there's a possible disconnect regarding the "the lower the better". At the end of the day, the Camera Dimensions seemed more important for us, because it finally determines pocket or bag in which the camera is carried.
In all the discussions about a best possible trekking camera, for example when a GH2 + lenses is suggested, some people will say that they prefer a 5D Mk II with a small prime lens. But then the GH2 could be used with a pancake lens as well. So we left out the lenses here.
I don't think it is useful to conflate such clear and precise information as weight and size, with the much more nebulous and endlessly disputed qualities of sensor and lens performance.
Aren't we doing this all the time when reading through any camera specs.
More or less intuitively we place bookmarks, at least in a notional sense, then trying to interpret and to interconnect this information:
a.) many Megapixel are basically good
b.) large Sensor Size is basically good
c.) large Pixel Size is basically good
d.) but then high Megapixel Density is typically bad
e.) high DxO Overall Score is considered to be good
f.) large Camera Dimensions are bad (for me)
So the logic suggests that:
high (a x b x c x e / f) is good
Megapixel Density d = Megapixel count a / Sensor Size b, makes b = a / d
Megapixel Density typically corresponds to the inverse Pixel Size, so the Pixel Size c is redundant.
= high [a x (a / d) x e / f] is good
= high [(a^2 x e) / (d x f)] is good
This is the inverse of the equation in my previous post which was set up to "low is good",
except that the absolute Megapixel count was missing.
Considering that many photo magazines are rating cameras by one single score number which mixes all kinds of attributes,
above approach is probably more at the conservative side.
Regards, Peter
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