Quote:
Originally Posted by Matsu
f/2.8 ISO 400 on APSC+0.67x reducer (net f/2 speed)
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A quibble only, but you mean a 0.71x reducer, i.e. 1/(square root of 2).
Edit: or more likely, you do mean 0.67x, but the f/2 speed is rounded. Fine.
Quote:
Originally Posted by Matsu
What does the dynamic range of a good 4/3rds sensor look like at ISO 200 vs a full frame sensor at 800?
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They'd be equal if the sensors were equally sophisticated, but at the moment most full-frame sensors, although not cutting-edge, are still far better than the 12-megapixel Four Thirds sensor.
Quote:
Originally Posted by Matsu
Of course you reserve the option to shoot the FF at lower ISO as well.
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Yeah: this is where the argument runs aground, I fear. And physics say we'll never overcome this either. Mid-tone grey at ISO 100 on an imaginary Four Thirds sensor with 100% quantum efficiency would still be noisier than mid-tone grey recorded by today's relatively inefficient full-frame sensors at ISO 100. No amount of new technology can change this: incoming light is just too noisy! The only way for Four Thirds to catch full-frame is by allowing much longer exposures, i.e. offering ISO 25, which can only be achieved by deeper electron wells; and since capacitance is closely related to area this is a hard ask (the old digital cameras with very low ISOs didn't have deeper wells, but rather less efficient micro-lenses — or none at all). Worse, any improvements to small sensors might be applied equally to larger ones.
Quote:
Originally Posted by Matsu
It would be really interesting to see some f/2.8 standard zoom designs reformulated into f/2 APSC designs. With an extra stop of brightness, and 50% greater spatial resolution
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41%, since gaining a stop would imply a 0.71x reducer. (And of course it would be a bit lower than 41% because of imperfect optics.)
Edit: I should leave rounded figures alone!
Quote:
Originally Posted by Matsu
After a fashion it makes sense to sell high-level, expensive APSC lenses and relatively cheaper APSC bodies. Lenses I will keep for a long time. Bodies I will recycle every 2-4 years... I don't believe that the price differential between APSC and 35mm should be so great, but maybe it is, and maybe that's where the manufacturers want to keep it?
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The idea of reducers, etc., is interesting, but it sounds a lot like Four Thirds, which failed because the cost of APS-C sensors plummeted, and even full-frame sensors were put into $3k cameras. Full-frame sensors admittedly have things against them from a manufacturing point of view, which makes them disproportionally expensive and forever doomed to be one step behind the cutting-edge of sensor developments. But this is more than made up for by their real performance advantage at base ISO, which cannot be regained by clever optics on an APS-C sensor, and by the strong emotional attachment to "full frame" — note my use of this loaded term throughout this post, for example!