andrewd01 Offline Upload & Sell: Off
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p.2 #14 · No talk about the Panasonic G1?? | |
olyacme wrote:
Vern Dewit wrote:
Yep - the intensity of light gathered by each lens is similar but the results after exposing the sensor to it are different, and that's what concerns most people... Isn't this stuff FUN?!
That's a winner of a sentence there!?
Probably the easiest way to describe format differences is in terms of the image circle emitted by a given lens. Different formats sample different amounts of that circle of light, in effect cropping to greater or lesser amounts. Ignoring vignetting, in all formats the light intensity per square mm of the sensor remains constant.
Different sensors have different sensel densities, which, along with evolving technology deliver differing peformances in noise, dynamic range, and demands on the optical performance of the lens. Assuming a constant MP count, smaller sensors demand higher resolution within a smaller circle, larger sensors demand lower resolution over a larger circle, for an equivalent result.
The typical "noise equivalence factor" argument, used to berate smaller sensors; that stopping down while increasing ISO will yield equivalent DOF and exposure duration without increased noise; assumes linear improvements in performance in step with sensel size. This may or may not be borne out in the real world, as manufacturing efficiencies allow more noise mitigation technology to be incorporated into smaller sensors without undue cost.
There's some info on the uFT M adaptor here: http://forum.getdpi.com/forum/showthread.php?p=63867#post63867


sweet looking rig (except for the red colour, what were you thinking?). Please post some images you have taken with this. I am tempted to get one of these as my travel cam, and an affordable way to use my M lenses on a digital camera.
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