06-26-2011, 09:32 AM
You're welcome to disagree of course, but I do not consider the sensor difference between m4/3 and APS-C as significant so would directly compare same actual focal length lenses between them. I can easily crop an APS-C image to m4/3 equivalent and get the same quality as m4/3. In fact I often crop much further since longer lenses are not really affordable.
I guess I should add, I'm only comparing field of views and disregarding depth of field effects. In this case the generalisation is bigger sensor = bigger lens. If you do depth of field equivalence too, then lenses would tend towards being the same size regardless of sensor size, apart from a smaller contribution from image circle size.
There's a lot to compare between lenses, so I wouldn't pick a single factor like weight. I would also consider the build quality, AF type and speed, optical qualities and other differentiators. There are only two areas of possible advantage for m4/3 from the mount compared to SLRs - possibly smaller lenses of focal length close to the mount distance from sensor plane, and possibly lighter lenses due to the limited image circle. So far EVIL lenses have used concious design relaxations to make lenses smaller, such as increased distortion that will be corrected later in software. And the contrast AF is not sensitive to aperture like phase is so they can make slower lenses that retain AF. This does allow some lenses to be a bit smaller than a hypothetical SLR equivalent since they rarely align exactly.
So having said that they're not comparable in a single way, I'm going to compare them in a single way. Just for fun here are some lengths taken from random sources:
Canon EF 70-300 IS USM 142mm
Canon EF 70-300 DO IS USM 100mm
Panasonic 100-300 126mm
Olympus 75-300 116mm
Not much difference is there? If anything the lens erection looks sillier as the body gets smaller in proportion.
To swing this back onto the Q, with the much smaller sensor, that will finally be able to realise much smaller lenses, although I will admit that will be at a different compromise of only comparing equivalent field of views, and not aperture.
In summary, I'm asking myself why am I even writing this? The sun is out, and I'm about to be also. <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='
' />
I guess I should add, I'm only comparing field of views and disregarding depth of field effects. In this case the generalisation is bigger sensor = bigger lens. If you do depth of field equivalence too, then lenses would tend towards being the same size regardless of sensor size, apart from a smaller contribution from image circle size.
There's a lot to compare between lenses, so I wouldn't pick a single factor like weight. I would also consider the build quality, AF type and speed, optical qualities and other differentiators. There are only two areas of possible advantage for m4/3 from the mount compared to SLRs - possibly smaller lenses of focal length close to the mount distance from sensor plane, and possibly lighter lenses due to the limited image circle. So far EVIL lenses have used concious design relaxations to make lenses smaller, such as increased distortion that will be corrected later in software. And the contrast AF is not sensitive to aperture like phase is so they can make slower lenses that retain AF. This does allow some lenses to be a bit smaller than a hypothetical SLR equivalent since they rarely align exactly.
So having said that they're not comparable in a single way, I'm going to compare them in a single way. Just for fun here are some lengths taken from random sources:
Canon EF 70-300 IS USM 142mm
Canon EF 70-300 DO IS USM 100mm
Panasonic 100-300 126mm
Olympus 75-300 116mm
Not much difference is there? If anything the lens erection looks sillier as the body gets smaller in proportion.
To swing this back onto the Q, with the much smaller sensor, that will finally be able to realise much smaller lenses, although I will admit that will be at a different compromise of only comparing equivalent field of views, and not aperture.
In summary, I'm asking myself why am I even writing this? The sun is out, and I'm about to be also. <img src='http://forum.photozone.de/public/style_emoticons/<#EMO_DIR#>/biggrin.gif' class='bbc_emoticon' alt='
' />
<a class="bbc_url" href="http://snowporing.deviantart.com/">dA</a> Canon 7D2, 7D, 5D2, 600D, 450D, 300D IR modified, 1D, EF-S 10-18, 15-85, EF 35/2, 85/1.8, 135/2, 70-300L, 100-400L, MP-E65, Zeiss 2/50, Sigma 150 macro, 120-300/2.8, Samyang 8mm fisheye, Olympus E-P1, Panasonic 20/1.7, Sony HX9V, Fuji X100.