But for all of that, for a given lens (in this case the 24-120 f4 VR), the difference between the D7100 and D750 images when the light is anything from reasonable to good, seems to be very little. If the new 16-80 is offered as a kit lens on the D7200, there is every chance that the DX would beat or be indiscernible from the FX D750 with the 24-120 I think.
Thanks for taking the time to look at them @WestEndFoto.
What do you think of the sharpness of that 24-120? I think it is pretty unspectacular.
Hmmm........
That is quite difficult to assess, based on the test. The lens is actually pretty sharp in the centre in my opinion. However, all lenses should be sharp in the centre at f/8. That is simply table stakes. It is why I like the MF lenses in my signature. I am using them for landscapes and even a 30 year old lens (admittedly a professional lens in its day) is sharp at f/5.6 to f/8.0 which is where I use them at. As an aside they are also sharp on the edges stopped down which makes them good for landscapes -though my 20mm is weak in this area.
I think the real test is shooting the lens at f/4.0 and comparing it to other lenses at f/4.0. A couple of years ago I did perform this experiment with the 24-70 2.8 and 70-200 2.8. They did not perform well against my primes and coupled with the fact that they only went to f/2.8 and I love bokeh, I opted for a prime strategy and have only bought the 14-24 2.8 because at 14mm, it performs better than the 14 2.8 prime.
That said, there is something about this lens that I don't like. However, I am unsure of my opinion because I am not able to properly test it. However, the feeling is strong.
Somehow it looks like my 28-200D lens. This is a lens I bought in the late 90s and is not in my signature because I think it is only good enough for a paperweight. I don't think it is as bad as my 28-200, but it has that "look" that I don't like.
My educated guess on what is causing the look is low edge contrast (not colour contrast) and spherical aberration. These attributes produce a slightly hazy look because even though the lens is sharp, small amounts of light from one part of the image are "leaking" over to other parts of the image. Also, human perception of sharpness is not only based on real sharpness, but also contrast. It is why using the sharpening tool in Lightroom or other programs increases perceived sharpness. They are increasing edge contrast. This deception convinces the human visual system that sharpness has increased. It is also why I could not figure out what the slider actually did that was beneficial in Lightroom until I learned this. It is not going to help much on a lens that is optically excellent - say a good prime. These already have good contrast and increasing the sharpness makes them look fake and harsh. When I took an image with my 28-200 and increased the sharpness in Lightroom, I could see the difference and it actually looked better. I should also note that I can make an image look better at normal screen resolutions by sharpening but when I zoom, I do not like the look so I don't do it. I should further note that when Lightroom uploads pictures to Flickr, I have it set to "Sharpen for Screen" in "Output Sharpening" as it is only going to be used for the screen.
However, back to this lens, I don't know for sure. However, I am putting my money on it being sharp, but somehow "hazy", likely due to sub-par performance relating to contrast and spherical aberration. This is not a negative against this lens. It is a 24-120 zoom for a little more than a thousand dollars. The performance issues that I am complaining about are actually quite subtle and well controlled compared to my 90s era 28-200. This lens therefore has no performance issue and is good value. I would highly recommend it for most people that want a zoom. If you want better like I do, you have to spend a lot more money and will likely end up with primes.
But for all of that, for a given lens (in this case the 24-120 f4 VR), the difference between the D7100 and D750 images when the light is anything from reasonable to good, seems to be very little. If the new 16-80 is offered as a kit lens on the D7200, there is every chance that the DX would beat or be indiscernible from the FX D750 with the 24-120 I think.
Wow.
That result would not surprise me. That would make it quite a decent DX lens indeed.
And I think that it reinforces that it is the lens that really matters, not the camera. Cameras are just photon detectors to be bolted onto the ends of lenses.
I could live with a cheap camera, but not a cheap lens.
I don't see any significant difference and that surprises me! I would think FX would be much easier to see detect as the "better" format. Perhaps the additional light FX gathers is just most apparent in giving us cleaner higher ISO's?
@Westendfoto - Wow thanks for the images along with the very valuable commentary. It's pretty clear that at least from a "real photography" standpoint your examples and conclusion seem very soon and true.
Let all beginners or amateurs take note.... An FX sensor does not produce "sharper" or "higher quality" images than a DX sensor all things being as equal as possible. In this regard lens choice remains king. That doesn't mean there aren't advantages to either FX or DX depending on your situation and clearly FX will give more options and flexibility (but sometimes with consequences such as size, price, etc).
It's just my opinion after starting this thread and reading all the commentary here, one should not be fearful to invest in the DX system or scared away by those comments out there that just say "FX makes better pics..."
Moments of Light - D610 D7K S5pro 70-200f4 18-200 150f2.8 12-24 18-70 35-70f2.8 : C&C very welcome! Being a photographer is a lot like being a Christian: Some people look at you funny but do not see the amazing beauty all around them - heartyfisher.
Hi all, I have had a very quick look at @spraynpray's images, thanks for that.. You did the D7100 vs D750. I dont have the D750 but I have the D610 and I recently got the D7200.. still not set up properly (the way I would like) but I have done some testing very simple, but I can say it is basically the same conclusions that was drawn between your D7100vsD750. Although, the D7200vsD610 has a few interesting "side notes". I will post the NEFs soon . :-) its uploading now :-)
Images taken with flash bounced off the ceiling ISO 100 F5.6 for D7200 and F5.6 and F8 for D610. Lense used 70-200 F4 about 100mm on D7200 and about 150mm on D610. (PS:Note that I have set my D610 to underexpose a bit by default)
Note I autofocused on the "al" of the word "Original". There seems to be some "front focus" on my new D7200 with this lense? may have to dial in some micro-adjustments ? and a bit of back focus on my D610 ?
Also I am sure you notice the flat profile on the D7200. It may make it looks less sharp due to the lower contrast .. dial up the contrast a bit and it turns out much better than the D610 !! I would say that the new D7200 performs much better (well maybe not "much" better but "pixel peeper" better) than the D610 with this lense, although the colours of the D610 ooc are awesome !!
Post edited by heartyfisher on
Moments of Light - D610 D7K S5pro 70-200f4 18-200 150f2.8 12-24 18-70 35-70f2.8 : C&C very welcome! Being a photographer is a lot like being a Christian: Some people look at you funny but do not see the amazing beauty all around them - heartyfisher.
Thanks for taking the time to look at them @WestEndFoto.
What do you think of the sharpness of that 24-120? I think it is pretty unspectacular.
My educated guess on what is causing the look is low edge contrast (not colour contrast) and spherical aberration. These attributes produce a slightly hazy look because even though the lens is sharp, small amounts of light from one part of the image are "leaking" over to other parts of the image. Also, human perception of sharpness is not only based on real sharpness, but also contrast. It is why using the sharpening tool in Lightroom or other programs increases perceived sharpness. They are increasing edge contrast. This deception convinces the human visual system that sharpness has increased. It is also why I could not figure out what the slider actually did that was beneficial in Lightroom until I learned this. It is not going to help much on a lens that is optically excellent - say a good prime. These already have good contrast and increasing the sharpness makes them look fake and harsh. When I took an image with my 28-200 and increased the sharpness in Lightroom, I could see the difference and it actually looked better. I should also note that I can make an image look better at normal screen resolutions by sharpening but when I zoom, I do not like the look so I don't do it. I should further note that when Lightroom uploads pictures to Flickr, I have it set to "Sharpen for Screen" in "Output Sharpening" as it is only going to be used for the screen.
However, back to this lens, I don't know for sure. However, I am putting my money on it being sharp, but somehow "hazy", likely due to sub-par performance relating to contrast and spherical aberration. This is not a negative against this lens. It is a 24-120 zoom for a little more than a thousand dollars. The performance issues that I am complaining about are actually quite subtle and well controlled compared to my 90s era 28-200. This lens therefore has no performance issue and is good value. I would highly recommend it for most people that want a zoom. If you want better like I do, you have to spend a lot more money and will likely end up with primes.
@spraynpray: Thank you! Now we know that there is no magical raise in image quality on fx.
Which is what I have been saying for a while now - ever since the D7000 I think. I do actually prefer my DX for macro due to the deeper DoF (which is still paper-thin) at magnifications approaching 1:1.
Now what we need is a comparison between the D7100 and D7200 by somebody with no axe to grind.
Hi all, I have had a very quick look at @spraynpray's images, thanks for that.. You did the D7100 vs D750. I dont have the D750 but I have the D610 and I recently got the D7200.. still not set up properly (the way I would like) but I have done some testing very simple, but I can say it is basically the same conclusions that was drawn between your D7100vsD750. Although, the D7200vsD610 has a few interesting "side notes". I will post the NEFs soon . :-) its uploading now :-)
Images taken with flash bounced off the ceiling ISO 100 F5.6 for D7200 and F5.6 and F8 for D610. Lense used 70-200 F4 about 100mm on D7200 and about 150mm on D610.
Note I autofocused on the "al" of the word "Original". There seems to be some "front focus" on my new D7200 with this lense? may have to dial in some micro-adjustments ? and a bit of back focus on my D610 ?
Also I am sure you notice the flat profile on the D7200. It may make it looks less sharp due to the lower contrast .. dial up the contrast a bit and it turns out much better than the D610 !! I would say that the new D7200 performs much better (well maybe not "much better" but "pixel peeper" better) than the D610 with this lense although the colours of the D610 ooc are awesome !!
If I were you I would up set both bodies up identically as otherwise it is a void comparison.
I have uploaded the NEFs so that has all the raw data for people to "equalise" the settings. The Jpgs will never be the same anyway.. new processor and algorithms between expeed 3 and 4..
Post edited by heartyfisher on
Moments of Light - D610 D7K S5pro 70-200f4 18-200 150f2.8 12-24 18-70 35-70f2.8 : C&C very welcome! Being a photographer is a lot like being a Christian: Some people look at you funny but do not see the amazing beauty all around them - heartyfisher.
Been poking around the DXO website recently and was surprised at the listed sharpness difference between the D750 and the D7100 using the 70-200 F4 - 22 Mpix vs. 13 Mpix. If there is a difference to be had between FX and DX surely it should be visible using a lens with that wide of a gap.
Is anyone able to take some shots with these combos of a detailed subject at 135mm F5.6 (which seems to be the lens's sweet spot) to compare?
Been poking around the DXO website recently and was surprised at the listed sharpness difference between the D750 and the D7100 using the 70-200 F4 - 22 Mpix vs. 13 Mpix. If there is a difference to be had between FX and DX surely it should be visible using a lens with that wide of a gap.
Is anyone able to take some shots with these combos of a detailed subject at 135mm F5.6 (which seems to be the lens's sweet spot) to compare?
I just got this lens in a few days ago and have really not shot with it yet other than a few test pics with the 810 to make sure it works. In general ANY lens will show the similar decrease in effective MP from FX to DX on the DXO website. I think this is because they are comparing the ability of a FX frame to resolve lines in a similar fill the frame comparison to a DX frame. I have roughly observed that the FX scores for a 24MP are about 1.5x the DX scores for a 24MP. However, as DXO is not really open about how the heck they are coming up with those numbers, no one really knows.
Been poking around the DXO website recently and was surprised at the listed sharpness difference between the D750 and the D7100 using the 70-200 F4 - 22 Mpix vs. 13 Mpix. If there is a difference to be had between FX and DX surely it should be visible using a lens with that wide of a gap.
Is anyone able to take some shots with these combos of a detailed subject at 135mm F5.6 (which seems to be the lens's sweet spot) to compare?
There is a critical difference between the DxO test and the tests that we ran.
Our test was at f/8.0 and f/11.0. The DxO tests are at the maximum aperture or wide open. Lens sharpness degrades quite significantly when it is wide open.
I will use the example of my 85 1.4G because it is a lens that I know the characteristics of well, I would expect an identical result between a D750 and D7200 at F/8.0. This is because the lens is sharper at f/8.0 than any current sensor’s sharpness, be it a 24 megapixel DX sensor using the sharp centre of the lens (about half of the image circle) or a 36 megapixel D810 sensor. Since the 24 megapixel DX sensor has a higher pixel density, as long as the lens is sharper than the DX sensor, the D750 and D7200 will produce an identical result.
I would imagine that this would be the same for most Nikon lenses. It is not that difficult to make a lens sharp at f/8.0. Apparently, Nikon has done it with the 24-120.
When the tests are performed with the lens wide open, I predict a different result.
The 85mm 1.4G is famous for being sharp wide open, but that is only in comparision to the 85mm 1.4D, which was relatively softer wide open, especially in the corners. However, I can tell you that from experience, wide open the lens is softer than my D800’s 36 megapixel sensor. Adding more megapixels will not make a difference. At some point, as you stop down, the lens becomes sharper than the sensor. I have not probed exactly where that point is, but my gut says that at f/4.0, I am not going to make the lens sharper on my D800’s sensor. Perhaps with a D7200 and a higher pixel density, that transition might be f/5.0 or f/5.6.
Since the lens is the limiting factor wide open, think of the lens as having a certain resolution. BVS, do you notice how the resolution on the DX sensor is about half the FX sensor? This is because the higher pixel density of the DX sensor is not helping sharpness because the FX sensor has either exceeded the sharpness of the lens or is close to the boundary. Note that a DX sensor is about half of the area of an FX sensor. Since both sensors are effectively identical for the DX portion of the lens, the FX sensor will achieve better sharpness and resolution results because it uses twice as much of the lens.
As sensor resolution increases (and therefore pixel density) I anticipate that this advantage of FX will become apparent at higher f-stops. How many megapixels does an FX sensor need to be before this is true even at f/5.6? (Note: F/5.6 is approximately the maximum sharpness of a really sharp lens, as stopped down past f/5.6 sharpness will decline due to diffraction. You can say that such a lens is diffraction limited at f/5.6. It is why I love my 28mm 2.8 AIS which is diffraction limited at f/5.6 in the centre and f/8.0 in the edges. You can also say that the lower the f-stop that a lens is diffraction limited, the sharper the lens. A lens that is diffraction limited at f/4.0 would truly be a sharp lens.) There is no real way to tell, but I imagine that it will be some time before we see that.
This is one reason that I have picked FX as a system, as I see this natural advantage of FX asserting itself as sensor resolution increases.
Also, I think this speaks to both a strength and weakness of DxO scores. I think that they are really onto something with their perceptual megapixel concept. It rings true and is essentially what Spraynpray and I tested with his D750/D7100 24-120 f/4.0 combo. The weakness is that they don’t do the same test at f/5.6, probably because they cannot until sensors increase in sharpness. The recent DxO test in the blog on the Voightlander Ultron 40mm f/2.0 is an example. According to DxO, it tested poorly at f/2.0. I just bought this lens and was shooting it this weekend. I can tell you that it is sharp for what I am using it for, f/5.6 – f/8.0 for landscapes etc. The DxO test results don’t help me much in this case.
There is a critical difference between the DxO test and the tests that we ran.
Our test was at f/8.0 and f/11.0. The DxO tests are at the maximum aperture or wide open. Lens sharpness degrades quite significantly when it is wide open.
Not to get too off topic, but I poked around the DXO site some more and it seems that the P-Mpix score is actually an 'average' score across the whole aperture and focal length ranges of the lens... which seems even less helpful than it just being the max at ideal settings or max wide open.
What's worse is that if you select a lens and go to Measurements -> Sharpness -> P-MPix Map it shows the change in P-MPix across different apertures, but there's no way to see the actual numbers on the graph (that I can tell), even though it would seem DXO has them.
Here's what DXO says about their Sharpness scoring:
The DxOMark resolution score shows sharpness performance of a lens-camera combination averaged over its entire focal length and aperture ranges.
The resolution score is computed as follows: For each focal length and each f-number, we first compute sharpness and then weight it throughout the field, tolerating less sharpness in the corners than in the center. This gives one number for each focal and aperture combination. Then, for each focal length, we select the maximal value of sharpness over the range of available apertures. We average this value over the whole range of focal length to obtain the DxOMark resolution score that we report (in P-MPix).
Note that for a wide-range zoom, there are huge differences between the resolutions for different focal lengths.
Sharpness is expressed in PMpix and is typically between 50% and 100% of the sensor pixel count, Differences below 1 P-MPix are usually not noticeable.
Best resolutions are usually attained for fixed focal lenses and moderate apertures (depending on the lens, between f/2.8 and f/8).
Good test run. You note that it was "quite gusty". This to me demonstrates that there is not a lot of difference. Most of my images are up for between 3 to max 5 seconds in a slide sound show and the difference there which I have often tested from D7100 and D700 to D810 with the same lens did not have enough difference to be too big a deal. However I would note these are pretty much lots of light and tripod shots. Very important in establishing what you were looking for and to show us any possible differences. My guess is that very low light photos which would be very hard to have the control you nicely achieved here would become much tougher. DX lens have up til now been very undeveloped by Nikon. Makes me wonder what the 16-80 DX will actually do. I would also be interested in spraynpray's take on D750 versus D810? Reason of course is that is a subjective view I would have to pay thousands to answer for myself.
Interesting BVS. For some reason I cannot access the DxO mark website to see individual web tests, though I am able to access the section that you linked too. However, on first glace, I need to rethink my assumption about the way they do their tests.
However, I do think my comments on FX being better than DX where the sensor is sharper than the lens is valid.
When I can access the DxO site, I will look at this more closely and see if something comes to mind.
Looks like the expeed 3 vs 4 is quite different as I wasn't able to get them as similar as I hoped.. so I am giving up .. (NOTE I have not been able to work out how to post images due to my access issues :-( )
( Fixed the back focus on the D7200/70-200f4 combo :-) )
Ok from what I see... from the new photos .. 1) Center is pretty much the same both are super sharp ! if I were really to nitpick the split hairs of a nit .. I would say the D610 is ahead but it may just be micro missed focus... 2) the edges the DX D7200 is clearly ahead at 100% crop .. I would say the D7200 at the edges are just as sharp as the center !! as I have nothing to look at for the far corners edges there is nothing to say about that accept it would probably be more of the same.
PS:I think i remember now .. i set the D610 for warmer output a while ago and forgot .. thats why the images have a warmer tone ! argh ! I am not redoing it! its all in the RAW files anyway !!
Post edited by heartyfisher on
Moments of Light - D610 D7K S5pro 70-200f4 18-200 150f2.8 12-24 18-70 35-70f2.8 : C&C very welcome! Being a photographer is a lot like being a Christian: Some people look at you funny but do not see the amazing beauty all around them - heartyfisher.
I bit slow to comment, but in Spraynpray's images...the little blue and white tag in the photo looked sharper from the D7100.
How much sharper....not enough to really make any decisions upon which to use, but I suppose the issue is whether one can take as good an image with a smaller sensor. Also, in spite of VR on the lens, I think test images may need to be done in controlled venues, always same light, no wind, etc., as looking at the image magnified many times may be identifying differences between the vibrations present from wind, even ground vibrations can affect this.
Interesting discussion but let's remember that in the original days the D1 had 2.66 MP on a crop sensor and billboards came out of these images.....
Could just be a difference in focus, but to me the spice in the bottom of the 5-spice bottle and the graphics of the spices on the bottle seems much more detailed on the D610 photo. But then, other areas look better on the D7200 photo.
Interesting discussion but let's remember that in the original days the D1 had 2.66 MP on a crop sensor and billboards came out of these images.....
A-men to that...
The conversation frankly should be over. It's definitive in my book that there simply are not obvious winners/losers here when talking IQ and image sharpness on a DX/FX sensor. It's about the lenses and then of course a few tradeoffs in regards to costs, size, depth of field (large or small) and then some features that may or may not be available in one of the platforms.
I think I can see why maybe Nikon is not really putting a whole lot of DX lens product out in the marketplace and also why Fuji is doing so well (relatively) and why they chose to invest in APS-C size'd sensor and tech. If we had amazing primes and zooms that were built for DX, smaller/lighter and less expensive but maintained great optical characteristics optimized for DX. Very few would really buy a large framed sensor. Even when it comes to DOF advantages, FX could be minimized by going with faster glass (56mm 1.2 vs 85mm 1.4, etc).
Could just be a difference in focus, but to me the spice in the bottom of the 5-spice bottle and the graphics of the spices on the bottle seems much more detailed on the D610 photo. But then, other areas look better on the D7200 photo.
I had a look at that area again, and it does seem that the D7200 is still back focused slightly ie the chess pieces in front of the 5 spice bottle looks to be in focus .. I have increased my AF fine tune by 1 more notch and it looks much better now maybe a touch over but much better than before.
Moments of Light - D610 D7K S5pro 70-200f4 18-200 150f2.8 12-24 18-70 35-70f2.8 : C&C very welcome! Being a photographer is a lot like being a Christian: Some people look at you funny but do not see the amazing beauty all around them - heartyfisher.
Pretty much agree. This thread has been a good exercise. It seems like sensor size gains for FX are offset by lens sweet-spot gains for DX. I think my two primary reasons for continuing to lust after FX are high-ISO abilities or the related extra stop worth of bokeh, and a larger viewfinder.
I can imagine a DX mirrorless in the form of the D750 body with a killer digital viewfinder could be my next body. Dreaming....
The conversation frankly should be over. It's definitive in my book that there simply are not obvious winners/losers here when talking IQ and image sharpness on a DX/FX sensor. It's about the lenses and then of course a few tradeoffs in regards to costs, size, depth of field (large or small) and then some features that may or may not be available in one of the platforms.
I think I can see why maybe Nikon is not really putting a whole lot of DX lens product out in the marketplace and also why Fuji is doing so well (relatively) and why they chose to invest in APS-C size'd sensor and tech. If we had amazing primes and zooms that were built for DX, smaller/lighter and less expensive but maintained great optical characteristics optimized for DX. Very few would really buy a large framed sensor. Even when it comes to DOF advantages, FX could be minimized by going with faster glass (56mm 1.2 vs 85mm 1.4, etc).
D7100, D60, 35mm f/1.8 DX, 50mm f/1.4, 18-105mm DX, 18-55mm VR II, Sony RX-100 ii
Comments
Wow.
That is quite difficult to assess, based on the test. The lens is actually pretty sharp in the centre in my opinion. However, all lenses should be sharp in the centre at f/8. That is simply table stakes. It is why I like the MF lenses in my signature. I am using them for landscapes and even a 30 year old lens (admittedly a professional lens in its day) is sharp at f/5.6 to f/8.0 which is where I use them at. As an aside they are also sharp on the edges stopped down which makes them good for landscapes -though my 20mm is weak in this area.
I think the real test is shooting the lens at f/4.0 and comparing it to other lenses at f/4.0. A couple of years ago I did perform this experiment with the 24-70 2.8 and 70-200 2.8. They did not perform well against my primes and coupled with the fact that they only went to f/2.8 and I love bokeh, I opted for a prime strategy and have only bought the 14-24 2.8 because at 14mm, it performs better than the 14 2.8 prime.
That said, there is something about this lens that I don't like. However, I am unsure of my opinion because I am not able to properly test it. However, the feeling is strong.
Somehow it looks like my 28-200D lens. This is a lens I bought in the late 90s and is not in my signature because I think it is only good enough for a paperweight. I don't think it is as bad as my 28-200, but it has that "look" that I don't like.
My educated guess on what is causing the look is low edge contrast (not colour contrast) and spherical aberration. These attributes produce a slightly hazy look because even though the lens is sharp, small amounts of light from one part of the image are "leaking" over to other parts of the image. Also, human perception of sharpness is not only based on real sharpness, but also contrast. It is why using the sharpening tool in Lightroom or other programs increases perceived sharpness. They are increasing edge contrast. This deception convinces the human visual system that sharpness has increased. It is also why I could not figure out what the slider actually did that was beneficial in Lightroom until I learned this. It is not going to help much on a lens that is optically excellent - say a good prime. These already have good contrast and increasing the sharpness makes them look fake and harsh. When I took an image with my 28-200 and increased the sharpness in Lightroom, I could see the difference and it actually looked better. I should also note that I can make an image look better at normal screen resolutions by sharpening but when I zoom, I do not like the look so I don't do it. I should further note that when Lightroom uploads pictures to Flickr, I have it set to "Sharpen for Screen" in "Output Sharpening" as it is only going to be used for the screen.
However, back to this lens, I don't know for sure. However, I am putting my money on it being sharp, but somehow "hazy", likely due to sub-par performance relating to contrast and spherical aberration. This is not a negative against this lens. It is a 24-120 zoom for a little more than a thousand dollars. The performance issues that I am complaining about are actually quite subtle and well controlled compared to my 90s era 28-200. This lens therefore has no performance issue and is good value. I would highly recommend it for most people that want a zoom. If you want better like I do, you have to spend a lot more money and will likely end up with primes.
And I think that it reinforces that it is the lens that really matters, not the camera. Cameras are just photon detectors to be bolted onto the ends of lenses.
I could live with a cheap camera, but not a cheap lens.
Let all beginners or amateurs take note.... An FX sensor does not produce "sharper" or "higher quality" images than a DX sensor all things being as equal as possible. In this regard lens choice remains king. That doesn't mean there aren't advantages to either FX or DX depending on your situation and clearly FX will give more options and flexibility (but sometimes with consequences such as size, price, etc).
It's just my opinion after starting this thread and reading all the commentary here, one should not be fearful to invest in the DX system or scared away by those comments out there that just say "FX makes better pics..."
Being a photographer is a lot like being a Christian: Some people look at you funny but do not see the amazing beauty all around them - heartyfisher.
You did the D7100 vs D750. I dont have the D750 but I have the D610 and I recently got the D7200.. still not set up properly (the way I would like) but I have done some testing very simple, but I can say it is basically the same conclusions that was drawn between your D7100vsD750. Although, the D7200vsD610 has a few interesting "side notes". I will post the NEFs soon . :-) its uploading now :-)
Ok here is the dropbox link ... https://www.dropbox.com/sh/4ucxkc4fnra69ma/AACJFKz4tJxsCgtLMkwY1bkza?dl=0
Images taken with flash bounced off the ceiling ISO 100 F5.6 for D7200 and F5.6 and F8 for D610. Lense used 70-200 F4 about 100mm on D7200 and about 150mm on D610. (PS:Note that I have set my D610 to underexpose a bit by default)
Note I autofocused on the "al" of the word "Original". There seems to be some "front focus" on my new D7200 with this lense? may have to dial in some micro-adjustments ? and a bit of back focus on my D610 ?
Also I am sure you notice the flat profile on the D7200. It may make it looks less sharp due to the lower contrast .. dial up the contrast a bit and it turns out much better than the D610 !! I would say that the new D7200 performs much better (well maybe not "much" better but "pixel peeper" better) than the D610 with this lense, although the colours of the D610 ooc are awesome !!
Being a photographer is a lot like being a Christian: Some people look at you funny but do not see the amazing beauty all around them - heartyfisher.
Now what we need is a comparison between the D7100 and D7200 by somebody with no axe to grind.
Being a photographer is a lot like being a Christian: Some people look at you funny but do not see the amazing beauty all around them - heartyfisher.
Is anyone able to take some shots with these combos of a detailed subject at 135mm F5.6 (which seems to be the lens's sweet spot) to compare?
Our test was at f/8.0 and f/11.0. The DxO tests are at the maximum aperture or wide open. Lens sharpness degrades quite significantly when it is wide open.
I will use the example of my 85 1.4G because it is a lens that I know the characteristics of well, I would expect an identical result between a D750 and D7200 at F/8.0. This is because the lens is sharper at f/8.0 than any current sensor’s sharpness, be it a 24 megapixel DX sensor using the sharp centre of the lens (about half of the image circle) or a 36 megapixel D810 sensor. Since the 24 megapixel DX sensor has a higher pixel density, as long as the lens is sharper than the DX sensor, the D750 and D7200 will produce an identical result.
I would imagine that this would be the same for most Nikon lenses. It is not that difficult to make a lens sharp at f/8.0. Apparently, Nikon has done it with the 24-120.
When the tests are performed with the lens wide open, I predict a different result.
The 85mm 1.4G is famous for being sharp wide open, but that is only in comparision to the 85mm 1.4D, which was relatively softer wide open, especially in the corners. However, I can tell you that from experience, wide open the lens is softer than my D800’s 36 megapixel sensor. Adding more megapixels will not make a difference. At some point, as you stop down, the lens becomes sharper than the sensor. I have not probed exactly where that point is, but my gut says that at f/4.0, I am not going to make the lens sharper on my D800’s sensor. Perhaps with a D7200 and a higher pixel density, that transition might be f/5.0 or f/5.6.
Since the lens is the limiting factor wide open, think of the lens as having a certain resolution. BVS, do you notice how the resolution on the DX sensor is about half the FX sensor? This is because the higher pixel density of the DX sensor is not helping sharpness because the FX sensor has either exceeded the sharpness of the lens or is close to the boundary. Note that a DX sensor is about half of the area of an FX sensor. Since both sensors are effectively identical for the DX portion of the lens, the FX sensor will achieve better sharpness and resolution results because it uses twice as much of the lens.
As sensor resolution increases (and therefore pixel density) I anticipate that this advantage of FX will become apparent at higher f-stops. How many megapixels does an FX sensor need to be before this is true even at f/5.6? (Note: F/5.6 is approximately the maximum sharpness of a really sharp lens, as stopped down past f/5.6 sharpness will decline due to diffraction. You can say that such a lens is diffraction limited at f/5.6. It is why I love my 28mm 2.8 AIS which is diffraction limited at f/5.6 in the centre and f/8.0 in the edges. You can also say that the lower the f-stop that a lens is diffraction limited, the sharper the lens. A lens that is diffraction limited at f/4.0 would truly be a sharp lens.) There is no real way to tell, but I imagine that it will be some time before we see that.
This is one reason that I have picked FX as a system, as I see this natural advantage of FX asserting itself as sensor resolution increases.
Also, I think this speaks to both a strength and weakness of DxO scores. I think that they are really onto something with their perceptual megapixel concept. It rings true and is essentially what Spraynpray and I tested with his D750/D7100 24-120 f/4.0 combo. The weakness is that they don’t do the same test at f/5.6, probably because they cannot until sensors increase in sharpness. The recent DxO test in the blog on the Voightlander Ultron 40mm f/2.0 is an example. According to DxO, it tested poorly at f/2.0. I just bought this lens and was shooting it this weekend. I can tell you that it is sharp for what I am using it for, f/5.6 – f/8.0 for landscapes etc. The DxO test results don’t help me much in this case.
What's worse is that if you select a lens and go to Measurements -> Sharpness -> P-MPix Map it shows the change in P-MPix across different apertures, but there's no way to see the actual numbers on the graph (that I can tell), even though it would seem DXO has them.
Here's what DXO says about their Sharpness scoring:
http://www.dxomark.com/About/Lens-scores/Metric-Scores
However, I do think my comments on FX being better than DX where the sensor is sharper than the lens is valid.
When I can access the DxO site, I will look at this more closely and see if something comes to mind.
https://www.dropbox.com/sh/4ucxkc4fnra69ma/AACJFKz4tJxsCgtLMkwY1bkza?dl=0
Looks like the expeed 3 vs 4 is quite different as I wasn't able to get them as similar as I hoped.. so I am giving up .. (NOTE I have not been able to work out how to post images due to my access issues :-( )
( Fixed the back focus on the D7200/70-200f4 combo :-) )
Ok from what I see... from the new photos ..
1) Center is pretty much the same both are super sharp ! if I were really to nitpick the split hairs of a nit .. I would say the D610 is ahead but it may just be micro missed focus...
2) the edges the DX D7200 is clearly ahead at 100% crop .. I would say the D7200 at the edges are just as sharp as the center !! as I have nothing to look at for the far corners edges there is nothing to say about that accept it would probably be more of the same.
PS:I think i remember now .. i set the D610 for warmer output a while ago and forgot .. thats why the images have a warmer tone ! argh ! I am not redoing it! its all in the RAW files anyway !!
Being a photographer is a lot like being a Christian: Some people look at you funny but do not see the amazing beauty all around them - heartyfisher.
How much sharper....not enough to really make any decisions upon which to use, but I suppose the issue is whether one can take as good an image with a smaller sensor. Also, in spite of VR on the lens, I think test images may need to be done in controlled venues, always same light, no wind, etc., as looking at the image magnified many times may be identifying differences between the vibrations present from wind, even ground vibrations can affect this.
Interesting discussion but let's remember that in the original days the D1 had 2.66 MP on a crop sensor and billboards came out of these images.....
The conversation frankly should be over. It's definitive in my book that there simply are not obvious winners/losers here when talking IQ and image sharpness on a DX/FX sensor. It's about the lenses and then of course a few tradeoffs in regards to costs, size, depth of field (large or small) and then some features that may or may not be available in one of the platforms.
I think I can see why maybe Nikon is not really putting a whole lot of DX lens product out in the marketplace and also why Fuji is doing so well (relatively) and why they chose to invest in APS-C size'd sensor and tech. If we had amazing primes and zooms that were built for DX, smaller/lighter and less expensive but maintained great optical characteristics optimized for DX. Very few would really buy a large framed sensor. Even when it comes to DOF advantages, FX could be minimized by going with faster glass (56mm 1.2 vs 85mm 1.4, etc).
Interesting times...
Being a photographer is a lot like being a Christian: Some people look at you funny but do not see the amazing beauty all around them - heartyfisher.
I can imagine a DX mirrorless in the form of the D750 body with a killer digital viewfinder could be my next body. Dreaming....