[Nesster]

Here's an interesting metric from dpreview's review of the Nikkor AF-S 50/1.4. You can toggle the graph etc between a D300 and a D3X.

Nikon AF-S Nikkor 50mm 1:1.4G review: Digital Photography Review

[jsherman999]

...
To me there's not much point going for FF citing a need for IQ if all that is being put in front of the FF sensor is consumer level glass. I have seen the difference in what FAJ and FA Ltd glass can produce, and having a FF sensor doesn't make the FAJ glass magically better than what comes out from an APS-C sensor.

It's not really magic - aps-c requires 'better' glass because of the magnification factor, just like m43 requires 'better' glass than aps-c, to get the same results. This can effectively be seen as the format leveling things off a bit.

I wouldn't go so far as to expect the FA-J 100-300 on FF to match the FA 200 macro on aps-c (pixel pitch similar,) but, for example, almost all Nikon shooters who have tried both would probably prefer the $300 Tamron 28-75 f/2.8 on FF vs the $1400 17-55 f2.8 on aps-c.

And I really, really think something like the simple, $150 F 50 1.7 would really shine on FF in several ways. I think the FA 20 2.8 would get new life, and the DA 200 2.8 would show a little vignetting at distance, but would be stellar. Then there's the FA Limiteds...

Put it this way: knowing what I know now, I'd rather shoot cheap-but-good glass on FF vs. expensive-and-great glass on aps-c. (I don't want to shoot 'bad' glass on either, though! )

.

[Ash]

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

Rob, the sensor technology between those two cameras is different, so of course the results will too reflect that. It is not just the format that determines the image output. A fairer comparison would be between a FF sensor made with the same wafer and camera processing technology as the APS-C camera. But I do agree there will be a lot of scrutiny of the FA limited series if Pentax do bring out a FF camera, since these lenses will be held up as being the gold standard of IQ in the K-mount.


Ash.

[Ash]

Here's an interesting metric from dpreview's review of the Nikkor AF-S 50/1.4. You can toggle the graph etc between a D300 and a D3X.

Nikon AF-S Nikkor 50mm 1:1.4G review: Digital Photography Review

Their quote:
Quite simply, at any given focal length and aperture, the lens will have a fixed MTF50 profile when expressed in terms of line pairs per millimeter. In order to convert to lp/ph, we have to multiply by the sensor height (in mm); as the full-frame sensor is 1.5x larger, MTF50 should therefore be 1.5x higher.

The sensor technology is also significantly better in the D800 compared to that of the D300.
Ash.

[Ash]

It's not really magic - aps-c requires 'better' glass because of the magnification factor, just like m43 requires 'better' glass than aps-c, to get the same results. This can effectively be seen as the format leveling things off a bit.

I wouldn't go so far as to expect the FA-J 100-300 on FF to match the FA 200 macro on aps-c (pixel pitch similar,) but, for example, almost all Nikon shooters who have tried both would probably prefer the $300 Tamron 28-75 f/2.8 on FF vs the $1400 17-55 f2.8 on aps-c.

And I really, really think something like the simple, $150 F 50 1.7 would really shine on FF in several ways. I think the FA 20 2.8 would get new life, and the DA 200 2.8 would show a little vignetting at distance, but would be stellar. Then there's the FA Limiteds...

Put it this way: knowing what I know now, I'd rather shoot cheap-but-good glass on FF vs. expensive-and-great glass on aps-c. (I don't want to shoot 'bad' glass on either, though! )

.

I think we actually agree, Jay. I don't dispute the fact that APS-C demands more centre IQ from lenses to result in good quality images but pixel density being equal and the resolution being proportionally equal between the formats, the result from the same lens would be the same, albeit with more captured in the frame from the FF camera.

This then opens the lens up to more IQ scrutiny in the edges and corners from the FF camera since most (if not all) lenses have considerable sharpness falloff the further away from the centre you go. This is most noticeable with consumer level glass. This is why I'm suggesting that unless high end glass is being used, the IQ advantages of a FF format are quite limited (AFAIK). Please note that I am only talking about equivalent sensor technology between the formats, not comparing between cameras like the 5DMkIII and the 60D or 7D.

The Tamron 28-75 is not a consumer-grade lens in my mind. It is a professional grade lens with a consumer grade price tag. The results from that lens match or even eclipse that of much more expensive glass in its focal range. I think with its IQ, there would be room to move for a FF camera to bring out the best in that lens, where it would act more like a true wide -normal zoom as opposed to a normal-mid telephoto zoom on APS-C.

By what you're saying though, Jay, you've experienced an improvement in your results by going FF but are they a result of the same lenses being used on the bigger format? And would others here want to have a FF K-mount camera and be happier with lenses like the FA 28-80 on it as opposed to staying APS-C and having the DA* 16-50 (in terms of IQ, ignoring any SDM issues)?

Of course, I suppose that if the FF comes out, it will not be left without at least one quality wide-normal zoom and one good telezoom to go with it, so I see my own point here as moot. But there is a financial investment in all this when the gear comes out, and matched IQ for IQ, the lenses have to perform especially in the edges for the virtues of FF to shine.


Ash.

[dtmateojr]

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.

Again you are ignoring technology and physics. A point-and-shoot now will have better IQ than the APS-C cameras 10 years ago. It's not just about the amount of light falling on the sensor.

[dtmateojr]

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.

Being anal with the terminology does not make things right. Your argument implies that smaller sensors have have different ISO sensitivity calibrations vs full frame. It also assumes that there are no optics in front of the sensor that affects light intensity.

Quite explains why a lot of people here are dying for a full frame. They want it for the wrong assumptions.

[Fogel70]

Again you are ignoring technology and physics. A point-and-shoot now will have better IQ than the APS-C cameras 10 years ago. It's not just about the amount of light falling on the sensor.

Yeah, and you can probably also find proof that a standard sports car is much faster than a F1 car, because today's sports cars are faster that a 50:s F1 cars.

[dtmateojr]

Yeah, and you can probably also find proof that a standard sports car is much faster than a F1 car, because today's sports cars are faster that a 50:s F1 cars.

No, in fact you are ignoring photography. You are just focused on the equipment which is typical of "photography" forums.

A photographer is not stupid to use the same exposure settings on a point-and-shoot vs a full frame. If a full frame goes iso 100 f11 at 1/125 a point and shoot will happily go f2.8 at 1/2000 without sacrificing IQ and DoF.

[Fogel70]

I'll say that FF give superior images with these setting in almost any case, as the FF has much wider DR at base ISO than a P&S.

[Rondec]

It's not really magic - aps-c requires 'better' glass because of the magnification factor, just like m43 requires 'better' glass than aps-c, to get the same results. This can effectively be seen as the format leveling things off a bit.

I wouldn't go so far as to expect the FA-J 100-300 on FF to match the FA 200 macro on aps-c (pixel pitch similar,) but, for example, almost all Nikon shooters who have tried both would probably prefer the $300 Tamron 28-75 f/2.8 on FF vs the $1400 17-55 f2.8 on aps-c.

And I really, really think something like the simple, $150 F 50 1.7 would really shine on FF in several ways. I think the FA 20 2.8 would get new life, and the DA 200 2.8 would show a little vignetting at distance, but would be stellar. Then there's the FA Limiteds...

Put it this way: knowing what I know now, I'd rather shoot cheap-but-good glass on FF vs. expensive-and-great glass on aps-c. (I don't want to shoot 'bad' glass on either, though! )

.

Maybe I have too many good lenses, because I have lots of pixel sharp photos on my K5 with the lenses I own. Anyway, I don't see how a K5 is any harder on a lens than a D800. Basically it exactly takes the center portion of the D800 photo, nothing more or less. How can you say that a K5 requires better glass than a D800?

It doesn't make any sense. Any more than the people who were complaining that the D800 had too many pixels as compared to the D700 and so it was "too hard" on glass. If you can take good photos with a K5, you probably can take them with a D800, as long as camera weight doesn't become an issue...

[dtmateojr]

I'll say that FF give superior images with these setting in almost any case, as the FF has much wider DR at base ISO than a P&S.

I don't think so. I highly doubt you can tell the difference. In good light my iphone will give comparable results vs other 8mp cameras especially that it can now capture RAW.

[Nesster]

A capture mechanism, film or sensor, has its own limits, let's say 100 lines per mm. When a larger capture area is involved, it makes sense the overall area is capable of more lines per mm than a smaller area. If two such frames, one 2x the other, are set to capture the same amount of scene, the larger system is working less hard than the smaller one (given the two have the same max resolution of 100 lpm). Or alternately, the larger system is capable of capturing many more lines across the frame. I like to think of it as a smaller format needs to pack the lines tighter than a lager one to get the same amount of information. When a sensor or film 'out resolves' a lens, it simply means the lens cannot pack those lines tight enough, and vice versa, a lens that 'out resolves' a sensor, it is capable of packing more information than the sensor can capture. On a larger surface, of course, other design problems are in play, such as vignetting and the retention of detail across the whole area... in the film days, if the film out resolved the lens, blur etc resulted, and if vice versa the detail was 'modified' by film grain etc. With digital we get some of this, but also aliasing and other such artifacts.

Another thought, let's think in terms of tape recorders. A large reel to reel going at fast speed has a lower noise floor and wider potential response than a cassette tape running at the slow rate they do. The reel to reel resolves more. To make cassettes acceptable, manufacturers resorted to various noise reduction schemes... which masked the noise or moved it...Then CD came along, and engineers applied NR plus the Nyquist filter (aka anti-alias) to get audio images that measured OK in noise etc. And nothing wrong there, much of this is enjoyable and just fine in decent conditions, and in situations where the highest fidelity and resolution won't be easily heard. Smaller sensors and especially higher pitched ones have to amplify and shape the inherent noise more aggressively than larger ones. Eliminating the Nyquist/anti-alias filter can allow more detail. Etc Etc. Oh, and as they discovered with CD mastering, a bit of 'dither' aka lowest significant bit noise increased the overall perceived resolution of the system (it evened out the distribution of values falling between bits).

However that's all moot. I'm happy with my iPOD feeding a tiny class D amp; a bit happier with the same feeding a vintage Marantz, but happiest with my Linn feeding single ended amps into Alnico loudspeakers. Clearly, I can take my iPOD and class D amp with mini speakers places where the Linn/tube amps/large speakers won't go.

[ElJamoquio]

Being anal with the terminology does not make things right.

Exactly. Finally, we agree.

[ElJamoquio]

No, in fact you are ignoring photography. You are just focused on the equipment which is typical of "photography" forums.

A photographer is not stupid to use the same exposure settings on a point-and-shoot vs a full frame. If a full frame goes iso 100 f11 at 1/125 a point and shoot will happily go f2.8 at 1/2000 without sacrificing IQ and DoF.

P&S would be at about ISO 2560 or so with your conditions given. I'd say that's quite a sacrifice in IQ even ignoring the ~5x reduction in resolution.