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View Poll Results: Would you buy a Pentax Full Frame DSLR?
Yes 15277.95%
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07-10-2013, 12:34 AM   #316
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QuoteOriginally posted by dtmateojr Quote
Re aperture size, you forget that it's a ratio. f5.6 is the same for any format. It let's exactly the same amount of light. Doh?
Not if using same FOV, f/1.9 on the 8.5mm normal prime on Q is 4.5mm, and f/1.9 on FA43 is 22mm.

07-10-2013, 01:08 AM   #317
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QuoteOriginally posted by Fogel70 Quote
Not if using same FOV, f/1.9 on the 8.5mm normal prime on Q is 4.5mm, and f/1.9 on FA43 is 22mm.
LOL! Fstop 101 for you:

An fstop is an fstop. Light intensity diminishes as the square of the distance (i.e. focal length). A point-and-shoot will have a smaller opening because it needs a shorter focal length to cover THE SAME FoV. An fstop is the same for all formats.
07-10-2013, 01:15 AM   #318
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QuoteOriginally posted by dtmateojr Quote
LOL! Fstop 101 for you:

An fstop is an fstop. Light intensity diminishes as the square of the distance (i.e. focal length). A point-and-shoot will have a smaller opening because it needs a shorter focal length to cover THE SAME FoV. An fstop is the same for all formats.
Yes, but a smaller sensor need the same aperture size as on a larger sensor to capture the same amount of light at a given shutter speed. Only if both sensors capture the same amount of light will IQ be the comparable on both.
07-10-2013, 03:58 AM   #319
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Those who believe in APS-C should not try to convert those who believe in FF, and vice versa. NONE of what we do (well, actually very little) is pragmatic or cost effective: these are either TOOLS if we make a living with them, or HOBBY OBJECTS if we don't. As a hobby object, all the money is out-go.

In the next 12 months, those who believe in FF and can afford it will get one or more; those who believe in APS-C will be tempted by the next generation of APS-C cameras; and those who can afford the 'upgrade' will buy one or more... Those of us who can't or won't afford either 'upgrade'? Surely we suck, our equipment is obsolete, and no amount of proof can change that ... NOT. But clearly we aren't of any use to Pentax in the short term

07-10-2013, 04:38 AM   #320
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QuoteOriginally posted by civiletti Quote
Patronizing or not, he effectively turned your argument against you.
What argument? That FF cameras are only better than APS-C cameras if lenses with excellent IQ are used? If so, show me the proof that a consumer grade FF compatible zoom will produce noticeably better results on a FF camera compared to that from the K-5 IIs (let's say).

I have posted many times in the past that FF is superior for sports, and I failed to mention it in my last expressed opinion. So sue me.


Ash.
07-10-2013, 04:39 AM   #321
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QuoteOriginally posted by Nesster Quote
Those who believe in APS-C should not try to convert those who believe in FF, and vice versa. NONE of what we do (well, actually very little) is pragmatic or cost effective: these are either TOOLS if we make a living with them, or HOBBY OBJECTS if we don't. As a hobby object, all the money is out-go.

In the next 12 months, those who believe in FF and can afford it will get one or more; those who believe in APS-C will be tempted by the next generation of APS-C cameras; and those who can afford the 'upgrade' will buy one or more... Those of us who can't or won't afford either 'upgrade'? Surely we suck, our equipment is obsolete, and no amount of proof can change that ... NOT. But clearly we aren't of any use to Pentax in the short term
Two thumbs up. Thank you for that.


Ash.
07-10-2013, 06:14 AM   #322
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QuoteOriginally posted by Fogel70 Quote
Yes, but a smaller sensor need the same aperture size as on a larger sensor to capture the same amount of light at a given shutter speed. Only if both sensors capture the same amount of light will IQ be the comparable on both.
What?!!! Obviously you do not understand the physics of photography.

fstop 102 for you:
Aperture is NOT equal to fstop. Fstop is the ratio between focal length AND aperture.
07-10-2013, 06:31 AM   #323
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QuoteOriginally posted by Ash Quote
Two thumbs up. Thank you for that.


Ash.
+1 to that.

07-10-2013, 07:18 AM   #324
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QuoteOriginally posted by dtmateojr Quote
In good light, yes. I doubt if you can identify which image is which.

Re aperture size, you forget that it's a ratio. f5.6 is the same for any format. It let's exactly the same amount of light. Doh?
It doesn't let in the same amount of light. F/5.6 has ~2.3x as much light fall on a full-frame sensor than an APS-C sensor.

They have the same lux.
07-10-2013, 07:38 AM   #325
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QuoteOriginally posted by ElJamoquio Quote
It doesn't let in the same amount of light. F/5.6 has ~2.3x as much light fall on a full-frame sensor than an APS-C sensor.

They have the same lux.
This, I have a problem with. The part of the sensor that is the same sees exactly the same amount of light with APS-C as with full frame. Sure, some of the sensor is cropped away, but that doesn't effect the fact that your shutter speed will be equivalent with APS-C and full frame if you use the same iso and aperture. That is what most people mean when they say that an f stop is an f stop.
07-10-2013, 09:35 AM   #326
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QuoteOriginally posted by dtmateojr Quote
What?!!! Obviously you do not understand the physics of photography.

fstop 102 for you:
Aperture is NOT equal to fstop. Fstop is the ratio between focal length AND aperture.
I fully understand what you say, but you don't seem to understand that the same exposure don't give same IQ on different sensor size.
Exposure do not take into account the sensors size, it's only about light per area unit size, but IQ is exposure x sensor area. So a smaller sensor need more light per area unit size to give same IQ as a larger sensor.
07-10-2013, 11:07 AM - 1 Like   #327
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QuoteOriginally posted by Ash Quote
What argument? That FF cameras are only better than APS-C cameras if lenses with excellent IQ are used? If so, show me the proof that a consumer grade FF compatible zoom will produce noticeably better results on a FF camera compared to that from the K-5 IIs (let's say).

I have posted many times in the past that FF is superior for sports, and I failed to mention it in my last expressed opinion. So sue me.


Ash.


"You Can Use Cheap Lenses!

I get better results on full-frame with crummy lenses than I do with my very best lenses on DX.

Having bigger pixels on a larger format means you can use cheaper lenses and usually get better results than the best lenses on a smaller format. The only reason I use the weasel word of "usually" is because as of 2007 we're only talking about a 1.6x linear format difference among consumer (under $9,000) DSLRs. In film, with a 2x linear difference from one format to the next, the crappiest lens on the next bigger format always smokes the very best lens on the next smaller format."

The Full-Frame Advantage
07-10-2013, 11:16 AM   #328
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QuoteOriginally posted by Ash Quote
Feeling 'useful' is different from gaining an IQ advantage. I agree that the FA 31 would be a very useful lens for wide angle applications, and it would suit it very nicely given its FF capability, but that wasn't my point. Images from DA 21 on APS-C vs images by the FA 31 on FF (at apertures giving equivalent DoF) would have reasonably comparable results - notwithstanding all that extra DoF capability of the FA 31 on the FF format.
Totally disagree. As I said in my previous post, the Sony 24MP FF sensor trounces the Sony 24MP APS-C sensor, as evidenced by the difference between the RX1 and the NEX 7. The same will hold true for the examples that you have given. I think that a big unknown is how well the FA Limited lenses will perform on high resolution FF sensors. Any lens flaws will become more evident.

Rob
07-10-2013, 12:08 PM   #329
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QuoteOriginally posted by Rondec Quote
This, I have a problem with. The part of the sensor that is the same sees exactly the same amount of light with APS-C as with full frame. Sure, some of the sensor is cropped away, but that doesn't effect the fact that your shutter speed will be equivalent with APS-C and full frame if you use the same iso and aperture. That is what most people mean when they say that an f stop is an f stop.
I said they have the same lux. They don't transmit the same amount of light.
07-10-2013, 12:09 PM   #330
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QuoteOriginally posted by robgo2 Quote
Totally disagree. As I said in my previous post, the Sony 24MP FF sensor trounces the Sony 24MP APS-C sensor, as evidenced by the difference between the RX1 and the NEX 7. The same will hold true for the examples that you have given. I think that a big unknown is how well the FA Limited lenses will perform on high resolution FF sensors. Any lens flaws will become more evident.

Rob

For center performance, we could just test on the Q.
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