Which setup will have faster shutter speed?
- Thread starter sin77
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Big Barrel has noting to do with that,
Aperture area[edit]
The amount of light captured by a lens is proportional to the area of the aperture, equal to:
Where f is focal length and N is the f-number.
The focal length value is not required when comparing two lenses of the same focal length; a value of 1 can be used instead, and the other factors can be dropped as well, leaving area proportion to the reciprocal square of the f-number N.
If two cameras of different format sizes and focal lengths have the same angle of view, and the same aperture area, they gather the same amount of light from the scene. In that case, the relative focal-plane illuminance, however, would depend only on the f-number N, so it is less in the camera with the larger format, longer focal length, and higher f-number. This assumes both lenses have identical transmissivity.
http://en.wikipedia.org/wiki/Aliasing
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barrel is bigger.......... like 大支就好? lol.
when the aperture setting is the same, it will be same amount of light reach the sensor, regardless different focal length lenses, different format cameras.
The thing that can think of that may give u different shutter speed is due to metering of each different camera?
If u r talking about absolute size of aperture, then yes (e.g 30mm, 57.8mm diameter etc).
But the f number on your camera is not an absolute size. It is a ratio..thus, barrel size is normalized in this case.
So answer is: same same. Heh.
Catchlights has provided a very clear explanation in post #10.
If I may add on, for the same f-stop a larger sensor would require a larger diameter lens, compare to a smaller sensor, to illuminate the entire sensor without vignetting. In absolute terms, for the above 2 lenses, the Nikon lets in more light. To picture this, imagine mounting the 2 lenses on a (hypothetical) camera with a 1/2" sensor. So your comment will be true in such a case. But when you couple these lenses to their corresponding format they achieve for their respective sensor the same illumination.
I can see where you are confused.
1. Yes, it is true that APS-C will have more light going in at f2.8 than m4/3 going in at f2.8
However APS-C lens will have to illuminate the entire APS-C sensor, while the m4/3 will only have to illuminate the m4/3 sensor. So it is the same shutter speed at the same ISO and aperture as explained in so many of the above posts already.
2. Now, since APS-C captures more light than m4/3 sensor, all things being equal (i.e. the sensors are the same), it would mean that there would be less noise with APS-C than M4/3.
As such, I think you are not asking the right question and thus, confusing yourself with the answer you want to hear.
3. Barrel has nothing to do with it - I'm not even sure what you mean by "barrel". If you mean the physical size, then I would personally prefer a smaller barrel for the same max aperture (f-stop) lens. f1.4 is f1.4, irregardless of size. However, I think what you mean is APS-C f1.4 vs m4/3 f1.4...which will be confusing.
Thanks for the explanation bro.
But I think point 2 about why APS-C having less noise is not totally accurate. Light collected per square unit of sensor is theoretically the same. The reason why a smaller sensor might exhibit more noise than a larger sensor has more to do with pixel density.
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