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09-30-2012, 06:27 AM   #16
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QuoteOriginally posted by fikkser Quote
They forgot the fast prime...

This system is made for FAST PRIMES, WHERE ARE THEY, DAMN IT.
A f/0.5 will be f/2.8 with the crop factor.

A 14mm/0.5 would be neat.

09-30-2012, 08:39 AM   #17
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QuoteOriginally posted by LamyTax Quote
No. Shutter speed is secondary.
Diffraction limit is what matters. >f/4 makes little sense with the Q because you effectively kill resolution due to diffraction.

F/2.8 on a Q is already similar to f/8 on APS-C.
F/2.8 = F/16 on FF or F/11 on APS-C
F/1.9 = F11 on FF or F/8 on APS-C

Fast primes? It's unreal. If they even make 10/1.0 = 56/5.6 on FF or 56/4 on APS-C...
09-30-2012, 09:26 PM   #18
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Well that is in regards to matching DOF and diffraction yes but stopwise 2.8 is 2.8 - If you are wanting limited DOF then you need the larger sensor camera.
10-01-2012, 12:21 AM   #19
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QuoteOriginally posted by Tonto Quote
Well that is in regards to matching DOF and diffraction yes but stopwise 2.8 is 2.8 - If you are wanting limited DOF then you need the larger sensor camera.
Aperture equivalence is more useful than just comparing DOF.
It also shows you the expected image quality in terms of noise and dynamic range when you are comparing different lenses with different sensors' size (assuming similar sensor technology), and how far a seemingly "fast" prime can offset the disadvantage of a small sensor.

10-01-2012, 02:05 AM   #20
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QuoteOriginally posted by ogl Quote
F/2.8 = F/16 on FF or F/11 on APS-C
F/1.9 = F11 on FF or F/8 on APS-C

Fast primes? It's unreal. If they even make 10/1.0 = 56/5.6 on FF or 56/4 on APS-C...
Yes, but why do you two compare with aps-c?

To compensate the Q's bad ISO we need faster lenses (I do atleast), doesn't require much glass to make a fast Q lens. If I could have some bookeh too, that would be nice. 10 f1 would be nice, give me.
10-01-2012, 01:20 PM   #21
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QuoteOriginally posted by ogl Quote
If they even make 10/1.0 = 56/5.6 on FF or 56/4 on APS-C...
But that should actually be fast enough to allow for some nice bokeh, at least at closer distances.
10-01-2012, 02:06 PM   #22
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I'm no expert, but aren't such ultrafast lenses difficult to make? They are rare, that's for sure.
10-03-2012, 01:26 AM   #23
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QuoteOriginally posted by fikkser Quote
They forgot the fast prime...

This system is made for FAST PRIMES, WHERE ARE THEY, DAMN IT.
The Q needs glass which is diffraction-limited at f/2.8 and does not fall off at wider apertures (if they exist). That's already rather hard to design for f/2.8. E.g., this is why for the Nokia 808, Zeiss made a fixed aperture lens (f/2.4).

10-03-2012, 03:35 AM   #24
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Yes, if you consider the former CCTV fast lenses samples, they are often wider than f/2.8, but very scarcely "HD compatible" at these apertures...
So i'm affraid that the cost of such primes would be very expensive.
But of course i wish there would be more of that choice in Q mount.
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