[Guest]

[quote name='Klaus' timestamp='1309079887' post='9558']The Pana 45-200mm f/4-5.6 OIS is just as small and heavy as the Canon 55-250/4-5.6 IS despite identical field-of-view in the respective format - just to give you a counter example.[/quote]



In reply to popos contribution I was looking at the "long" tele zooms only.

[Klaus]

[quote name='Brightcolours' timestamp='1309080505' post='9559']

Those are the actual facts... get an equivalent lens on MFT, and it will NOT be lighter. As my example of the 35mm f2 lens shows. Want me to give more examples?

[/quote]



Depth-of-field is just one aspect though. MFT allows 4 times faster shutter speeds at comparable depth-of-fields (2 times vs APS-C). At comparable megapixels you've a higher pixel density so you need faster shutter speeds anyway but you still have an advantage of about 1 f-stop. This can also be a decisive point.



Anyway, the discussion is sort of pointless. Mirrorless systems are about size and depth-of-field potential is not a priority here. Oly will release a 45mm f/1.8 soon - that's equivalent to a 90mm f/3.6 which sounds reasonably good for me for shallow depth-of-field situations.

[popo]

[quote name='Klaus' timestamp='1309081980' post='9562']

Depth-of-field is just one aspect though. MFT allows 4 times faster shutter speeds at comparable depth-of-fields (2 times vs APS-C). At comparable megapixels you've a higher pixel density so you need faster shutter speeds anyway but you still have an advantage of about 1 f-stop. This can also be a decisive point.



Anyway, the discussion is sort of pointless. Mirrorless systems are about size and depth-of-field potential is not a priority here. Oly will release a 45mm f/1.8 soon - that's equivalent to a 90mm f/3.6 which sounds reasonably good for me for shallow depth-of-field situations.

[/quote]

On the faster shutter, that only holds if you disregard quality variation with ISO setting, where the bigger sensor would in theory be able to produce comparable quality at a higher ISO setting, giving you that shutter time back.



Agree on the 2nd point. End of the day mirrorless (of any sensor size) brings with it a different set of advantages and disadvantages compared to SLR, so to me makes a great complement.

[Brightcolours]

[quote name='Klaus' timestamp='1309081980' post='9562']

Depth-of-field is just one aspect though. MFT allows 4 times faster shutter speeds at comparable depth-of-fields (2 times vs APS-C). At comparable megapixels you've a higher pixel density so you need faster shutter speeds anyway but you still have an advantage of about 1 f-stop. This can also be a decisive point.



Anyway, the discussion is sort of pointless. Mirrorless systems are about size and depth-of-field potential is not a priority here. Oly will release a 45mm f/1.8 soon - that's equivalent to a 90mm f/3.6 which sounds reasonably good for me for shallow depth-of-field situations.

[/quote]

About the speed of the shutter... that is kind of incorrect. The light captured by the 4/3rds sensor will be 1/4th of what the FF sensor receives. To equalize that, the amplification of the received signal is higher, just to reach the same "ISO value" (making ISO values really rather meaningless, in digital photography... it is not about sensitivity anymore).

So.. while 4/3rds does the extra amplification before the ISO settings already, set the FF camera to do the same amplification via the ISO setting itself. So, ISO 100 on 4/3rds, then ISO 400 on FF. Equivalent field of view, equal aperture/equivalent f-value, equal exposure time, equivalent ISO setting.



Of course it is right, DOF is not a priority there (with EVILs). But a factor anyway, if one does comparisons as above. The DOF freedom is the reason for the FF or APS-C DSLRs.



And yes, a 90mm f3/5 is reasonable. Comparable to the Tamron 60mm f2, Nikon 60mm f2.8, Canon 60mm f2.8, kind of.

[Guest]

[quote name='Klaus' timestamp='1309081980' post='9562']Mirrorless systems are about size...[/quote]



... and weight.

[Klaus]

[quote name='Brightcolours' timestamp='1309082909' post='9564']

About the speed of the shutter... that is kind of incorrect. The light captured by the 4/3rds sensor will be 1/4th of what the FF sensor receives. To equalize that, the amplification of the received signal is higher, just to reach the same "ISO value" (making ISO values really rather meaningless, in digital photography... it is not about sensitivity anymore).

So.. while 4/3rds does the extra amplification before the ISO settings already, set the FF camera to do the same amplification via the ISO setting itself. So, ISO 100 on 4/3rds, then ISO 400 on FF. Equvalent field of view, equal aperture/equivalent f-value, equal exposure time, equivalent ISO setting.



Of course it is right, DOF is not a priority there (with EVILs). But a factor anyway, if one does comparisons as above. The DOF freedom is the reason for the FF or APS-C DSLRs.



And yes, a 90mm f3/5 is reasonable. Comparable to the Tamron 60mm f2, Nikon 60mm f2.8, Canon 60mm f2.8, kind of.

[/quote]







Well, in this case you may argue that FF has little advantage in terms of noise because the comparable ground would be ISO 100 (MFT) vs ISO 400 (FF) thus compensating the higher speeds on the MFT side. There's still the higher speed requirement on the MFT side due to the smaller allowed circle-of-confusion - thus a one stop advantage for FF.



e.g. 9mm f/5.6 (MFT) at ISO 100 ~ 18mm f/11 (FF) at ISO 400.

[popo]

[quote name='Sammy' timestamp='1309083779' post='9565']

... and weight.

[/quote]

Different people have different needs, but to me weight is way down the priority list. The only time I bother looking at weights is when they start going over 2kg... and even then it is still secondary to size.

[Brightcolours]

[quote name='popo' timestamp='1309085132' post='9567']

Different people have different needs, but to me weight is way down the priority list. The only time I bother looking at weights is when they start going over 2kg... and even then it is still secondary to size.

[/quote]

And i find it very hard to complain about the weight of my EOS 450D + 35mm f2...

[Brightcolours]

[quote name='Klaus' timestamp='1309084049' post='9566']

Well, in this case you may argue that FF has little advantage in terms of noise because the comparable ground would be ISO 100 (MFT) vs ISO 400 (FF) thus compensating the higher speeds on the MFT side. There's still the higher speed requirement on the MFT side due to the smaller allowed circle-of-confusion - thus a one stop advantage for FF.



e.g. 9mm f/5.6 (MFT) at ISO 100 ~ 18mm f/11 (FF) at ISO 400.

[/quote]

You can't really argue that though... Usually one really does not neeed to mind the shutter speeds... 2000th of a sec or 250th of a sec, both will be fast enough.



So, in most situations, you can easily drop the ISO setting because you have the exposure time freedom.



Also, when light gets really low, you have the opportunity to use larger apertures too.



But yes, if you make everything equivalent, including the exposure time, the noise advantage of FF disappears.



You do not need a higher speed time on MFT, to compensate smaller pixels... the field of view is the same (even though the focal length for FF is bigger.. this due to the cropping) and the print size will be the same (even though the sensor is smaller, equaling out the circle of confusion factors.

[Klaus]

[quote name='Brightcolours' timestamp='1309088088' post='9569']

You can't really argue that though... Usually one really does not neeed to mind the shutter speeds... 2000th of a sec or 250th of a sec, both will be fast enough.

[/quote]



Well, you could e.g. design a MFT sensor with a min. ISO of 25 (vs ISO 100 FF). That should be fairly easy actually.

The "problem" is that most MFT users choose an aperture that they got used to on a FF camera so ISO 25 "appears" to be slow.



[quote name='Brightcolours' timestamp='1309088088' post='9569']

You do not need a higher speed time on MFT, to compensate smaller pixels... the field of view is the same (even though the focal length for FF is bigger.. this due to the cropping) and the print size will be the same (even though the sensor is smaller, equaling out the circle of confusion factors.

[/quote]



Point taken.