p.5 #1 · Giving up 5D II for NEX? My experience in Japan
briantho wrote:
Could you explain this a bit more? From my experience you can get razor thin dof with the NEX depending on the lens.
What's the difference between FF and APS-C? 1mm vs 2mm in focus? And when do you need more narrow dof than for instance the below examples? Couldn't it actually be that the minor difference in dof between FF and APC-C actually is more to the advantage of the smaller sensor?
p.5 #2 · Giving up 5D II for NEX? My experience in Japan
It's not just about razor thin DOF, but also the wideangle perspective.
Which lens on a NEX gives you the same 35mm FOV, with the same DOF capabilities?
None (that I know of anyway).
That's what I love the most about FF. A wideangle (non close-up) shot, but still having the choice to isolate a subject. It gives a special look that I only see with FF (and medium/large format).
I'm still tempted to buy a NEX, but it will not replace my 5DII.
p.5 #3 · Giving up 5D II for NEX? My experience in Japan
Well in that case maybe the dog pic was a bad example. I don't have any good examples, but in this pic with a bit of coverage, the dof is pretty narrow.
No way around the fact a FF sensor would be preferable, not only for thin DOF in a larger FOV, but for plain old speed--if I'm not mistaken. But the only FF that's portable is the M9: expensive and very unreliable. The horror stories at RFF are leigon. Worse, the wait for repair can be months. Far less flexible than the nex in terms of glass as well---but no doubt it can use some of the very best, and you can tell in the images.
I'm very impressed with how well you guys are doing---philber: your japan set is unreal, and sebboh's last are flat out gorgeous. Very inspiring.
My world is going white in a hurry, and i need to learn to shoot it better, that's for sure.
At this point I can't say I don't have the glass, hehe.
p.5 #5 · Giving up 5D II for NEX? My experience in Japan
briantho wrote:
Well in that case maybe the dog pic was a bad example. I don't have any good examples, but in this pic with a bit of coverage, the dof is pretty narrow.
Not a good example - the angle of view isn't very wide.
Anyway, there's a stop of difference between ASP-C and FF for the same framing:
Do you see - it's a wide angle of view and a shallow DOF. Larger formats do this even better of course - you can't get the same look with FF as with medium format or large format.
Edit: I see that sebboh was quicker in posting my examples Well, we seem to be in agreement.
p.5 #6 · Giving up 5D II for NEX? My experience in Japan
Thanks, I get it, I agree that wide angle is where the NEX and all APS-C cameras loses out. On the other hand, you get a real bonus on the tele end.
I can imagine if you don't care about very thin depth, but still want to use available light to your advantage, that the APS-C sensor could be preferable.
In a couple of years, I'm pretty sure FF sensors will be the standard for all mid-level cameras (where APS-C is now), and we will have the same discussion, only it will be MF vs FF.
p.5 #7 · Giving up 5D II for NEX? My experience in Japan
You don't have to have a Zeiss 35/1.4 to take advantage of FF. Even inexpensive lenses like a Olympus 50/1.8 or a Yashica 50/2, used wide open, will give you results you can't get with a APS-C camera.
p.5 #8 · Giving up 5D II for NEX? My experience in Japan
briantho wrote:
Thanks, I get it, I agree that wide angle is where the NEX and all APS-C cameras loses out. On the other hand, you get a real bonus on the tele end.
ASP-C is a crop factor and the name means exactly what it implies. If you have the same pixel density on an ASP-C and a FF sensor then doing a simple crop in photoshop on the FF picture you'll end up with an image that is identical to the one taken with an ASP-C.
In practice ASP-C cameras have a higher pixel density. The NEX 5N for instance is an 16 megapixel camera that has a 15.6x23.4mm sensor, giving a pixel density of ~ 44,000 pixels / mm^2. A 5DII on the other hand has 21 Mpixels on a 24x36 sensor giving a pixel density of 24,000 pixels/mm^2. (A FF camera with the same pixel density of the NEX-5N would have to be around 38 megapixel.)
What does that mean? A higher pixel density means smaller pixels that are more susceptible to noise. Furthermore it puts much more strain on a lens. Smaller pixels = higher spatial frequency required to resolve a given image which in turn means lower (micro)contrast.
So while you do get a boost on the tele end when using a crop sensor (your 100mm becomes the equivalent of 150mm and so on), you get this at a very high price - a significant drop in quality as you are asking much more from the lens.
I can imagine if you don't care about very thin depth, but still want to use available light to your advantage, that the APS-C sensor could be preferable.
Not quite, FF sensors have typically larger physical pixels on the sensor meaning that the noise levels are lower. So you'll get better high ISO performance.
p.5 #9 · Giving up 5D II for NEX? My experience in Japan
I think FF sensors will be limited to pro/enthusiast cameras in the near future, possible for a very long time. The advantages of a FF sensor is something a very very small part of the consumers are even aware of, less so willing to pay for it.
My guesstimation is that DSLR sales are going to decline in favor for EVIL cameras, and we don't even have a FF EVIL today. And if someone were to announce such a camera, they basically will need a new set of lenses, possibly a new mount. On top of that, the production cost for a FF sensor is a lot more than a crop. However, there are one manufacturer which have everything they need to build a FF EVIL, including a consumer base not afraid of using the available manual focus lenses ...
p.5 #10 · Giving up 5D II for NEX? My experience in Japan
JonasY wrote:
I think FF sensors will be limited to pro/enthusiast cameras in the near future, possible for a very long time. The advantages of a FF sensor is something a very very small part of the consumers are even aware of, less so willing to pay for it.
My guesstimation is that DSLR sales are going to decline in favor for EVIL cameras, and we don't even have a FF EVIL today. And if someone were to announce such a camera, they basically will need a new set of lenses, possibly a new mount. On top of that, the production cost for a FF sensor is a lot more than a crop. However, there are one manufacturer which have everything they need to build a FF EVIL, including a consumer base not afraid of using the available manual focus lenses ......Show more →
Sony needs to do a lot better on the corners of the frame with wide angle lenses before advancing on to FF. Maybe they would (should?) need to increase the FTF registration distance for FF? Seems something needs to be done for the current situation using APS-C
p.5 #11 · Giving up 5D II for NEX? My experience in Japan
denoir wrote:
Furthermore it puts much more strain on a lens. Smaller pixels = higher spatial frequency required to resolve a given image which in turn means lower (micro)contrast.
So while you do get a boost on the tele end when using a crop sensor (your 100mm becomes the equivalent of 150mm and so on), you get this at a very high price - a significant drop in quality as you are asking much more from the lens.
This is becoming OT but...
Interesting, I've heard this before, but have never seen any evidence of the supposed lower quality you mention. Do you have a link comparing the same lens on a cropped FF image and an APS-C image, showing this drop in quality? Because what you are actually saying is that for a future FF 38 megapixel camera (same density as the NEX you are comparing), you would have a "significant drop in quality" compared to the current 5DII with its 21 megapixels with the same lens.
Again, I could be wrong, would love to see a comparison. Would do it myself if I had a 5DII.
p.5 #12 · Giving up 5D II for NEX? My experience in Japan
Philippe - coming in late to this thread. Wonderful shots from Japan. All years I grew up there. I did not see what you saw. Sake barrels, something I took for granted ( duh ) really struck me with that thought. Wonderful.
Regarding giving up 5D II for Nex. This is all a matter of personal choice. I really like NEX, but I do not trust Sony enough to go all the way. Their investment in photos are only from recent years, and I still do not trust they are very serious about this sector. Audio and Video is what made them famous for, photos are their recent 'flirt'. I have experienced many Sony products/formats getting 'end of lifed' from their marketing decision, I suspect newer division is more vulnerable. Talking about format, if / when they decide to introduce FF version of NEX,I wonder what they would do to the current mounts and the lenses. Companies like Canon, Nikon, Leica, whose reputation is based on their photo business, feel more solid. Once again, I have never sold my gear off to switch, and that is not really my style. That in itself affect my comment here. Good luck with your decision, but I sort of know already that I will miss your planar shots with 5D II. That is an end of an era.
p.5 #13 · Giving up 5D II for NEX? My experience in Japan
briantho wrote:
Interesting, I've heard this before, but have never seen any evidence of the supposed lower quality you mention. Do you have a link comparing the same lens on a cropped FF image and an APS-C image, showing this drop in quality? Because what you are actually saying is that for a future FF 38 megapixel camera (same density as the NEX you are comparing), you would have a "significant drop in quality" compared to the current 5DII with its 21 megapixels with the same lens.
Per pixel level, yes of course.
I belive that a high quality lens can't be a bottle neck when it comes to resolution, after all, all it does is let throgh clean, concentrated light. It's the sensor receiveing and interpreting that light which must perform well.
Hehe, if only it was so. Unfortunately lenses are the primary bottle neck for resolution, no matter how high quality they are. The more you push them the lower micro contrast you get. That's what MTF charts show you.
Here's an often-posted example. The lens in question is the Leica 35/1.4 Summilux-M ASPH, one of the highest performing 35mm lenses in the world.
If we look at the 40 line pair/mm spatial resolution (the lowest two curves in the MTF) and plot them on how we expect the resolution to vary across the image:
Again, I could be wrong, would love to see a comparison. Would do it myself if I had a 5DII.
I can dig something out, but you have to be more specific of what kind of comparison you want. If it's the per pixel quality of the 5DII vs for instance the 7D using the same lens that's trivial, and I'm sure I can find some examples.
p.5 #14 · Giving up 5D II for NEX? My experience in Japan
sebboh wrote:
you can certainly get extremely thin dof with the NEX. it's the combination of narrow dof, field of view, and distance from subject that you can get with a fast wide on FF but not on a cropper. here's a few of examples that hopefully luka won't mind me stealing, which i believe cannot be replicated with a 1.5x crop camera and any current lens:
Although since most of these are static subjects, you could certainly get this kind of look with one of those shallow DoF panoramas. Plenty of examples in the pano thread.
p.5 #15 · Giving up 5D II for NEX? My experience in Japan
denoir wrote:
I can dig something out, but you have to be more specific of what kind of comparison you want. If it's the per pixel quality of the 5DII vs for instance the 7D using the same lens that's trivial, and I'm sure I can find some examples.
Found this test which shows the complete opposite of what you are saying. APS-C has the advantage for tele precisley because of better sensor resolution. Makes sense.
p.5 #16 · Giving up 5D II for NEX? My experience in Japan
I think you should read that again, as you've clearly misunderstood it. Or rather, I think you should probably read up a bit on optics as this is relatively basic stuff.
Anyway, as for the example you requested - here's the same subject shot with a 7D and a 5DII with a Zeiss 100/2 Makro-Planar. The camera position was moved to match the field of view so we would get the same framing:
As expected the 5DII shows much better micro contrast as the lens isn't taxed nearly as much as in the 7D case. This was entirely predictable from the MTF chart for the Zeiss 100 MP:
Going from FF->ASP-C while maintaining the same framing means that you're pressing the lens to resolve 1.6x (in the case of the 7D) more. In short it's going from 20 lp/mm -> 32 lp/mm and you can in the MTF chart see the difference between 20 & 40 lp/mm where the contrast drops from 80% to below 60%. And that's what we're seeing in the image.
What happens if we don't match the field of view, but keep the camera in the same place:
What would happen if we magnified the FF image to match the crop - i.e is there an advantage to doing it optically with a crop sensor rather than in photoshop?
The answer is yes, and that's what the author of the text was talking about - if you magnify something it gets larger and you see more detail. What he didn't say is that the price is a significant drop in quality. So you do get a bit more magnification and can see more detail, but it's at the expense of a narrow field of view and that the quality of the detail is much lower.
p.5 #17 · Giving up 5D II for NEX? My experience in Japan
denoir wrote:
I think you should read that again, as you've clearly misunderstood it. Or rather, I think you should probably read up a bit on optics as this is relatively basic stuff.
Okay... I have clearly misunderstood you. Sorry...
I do understand that if you move the camera to match the fov, or if you mount a longer tele on the 5DII, the FF camera will perform better always. But that's not what I ment with "bonus on the tele-end".
Edit: I also understand that if you MAGNIFY the smaller image, you will of course get crappy results. But we were talking about lens resolution, right?
denoir wrote:
So while you do get a boost on the tele end when using a crop sensor (your 100mm becomes the equivalent of 150mm and so on), you get this at a very high price - a significant drop in quality as you are asking much more from the lens.
I interpret the above statement as such that I would get a drop in quality on NEX because the lens can't provide the required resolution.
What I ment the test to be was:
1. Mount a good ~200mm lens on your 5DII and take an image of a distant subject.
2. Mount the same lens on the NEX. Take the same shot.
3. In PP, crop the 5DII image to correspond to the NEX image, so they are identical.
4. Compare quality.
I think the NEX is equal or better than 5DII regarding image quality in the above test.
The test would show that the lens resolution is NOT restricting results. Sorry if I didn't make it clear.
p.5 #18 · Giving up 5D II for NEX? My experience in Japan
denoir wrote:
Going from FF->ASP-C while maintaining the same framing means that you're pressing the lens to resolve 1.6x (in the case of the 7D) more. In short it's going from 20 lp/mm -> 32 lp/mm and you can in the MTF chart see the difference between 20 & 40 lp/mm where the contrast drops from 80% to below 60%. And that's what we're seeing in the image.
That explains why I never felt the need for sharpening my images while using a 1Ds with C/Y Zeiss lenses, while I noticed that the NEX files do take a fair amount of sharpening .
I would love a FF light camera with in body stabilisation
p.5 #20 · Giving up 5D II for NEX? My experience in Japan
briantho wrote:
I interpret the above statement as such that I would get a drop in quality on NEX because the lens can't provide the required resolution.
It is precisely because of that. The core of the problem is that there isn't such a thing as resolution. There is contrast at a given spatial frequency. That's what MTF charts show you. A lens can handle coarse detail with a high contrast but as you go down to finer and finer detail the contrast drops. This is entirely due to the lens.
A 5DII produces an image that is 5616 pixels wide and it's spread across a sensor that is 36mm wide. A 7D produces an image that is 5184 pixels wide and is spread across a sensor that is 22.3 mm wide. That means that the maximum theoretical resolving power of the 5DII is (5616 /2)/36 = 78 lp/mm while the corresponding number for the 7D is (5184/2)/22.3 = 116.2 lp/mm.
We saw in the MTF chart for the 100 MP that when going from 10lp/mm to 20lp/mm the contrast drops from 90% to 80% and when going from 20 lp/mm to 40 lp/mm the contrast drops from 80% to 60%. Assuming the rest follows in a linear fashion 80 lp/mm (~5D2) will give us a 20% contrast while at around 100 lp/mm we're down to zero - i.e you can't see the detail because the contrast is non-existent.
In short, the resolution, or rather the contrast at a given spatial frequency is entirely lens dependent. A smaller sensor will try to resolve a higher spatial frequency because its pixel density is higher and subsequently it will suffer from an overall drop in quality. And that's why the per pixel quality of the 5DII image will be higher compared to the 7D image.
The test would show that the lens resolution is NOT restricting results. Sorry if I didn't make it clear.
Look at my previous post, I added exactly that test.
Edit: If you are specifically interested in a NEX test, here's an old comparison between the NEX C3 and the M9:
denoir wrote
The lens used in all tests was the Zeiss 25/2.8 Biogon ZM. It holds the distinction of being the lens with highest recorded resolving power (400 lp/mm, MTF10) so it outresolves any existing sensor - a full frame sensor of over 500 megapixel would be required to make full use of the resolution of the lens.
What would happen if we reduced the C3 image size to match the M9 FOV? I.e could you use the C3 as the equivalent of a tele converter, or are you better off just cropping an M9 file:
Close, but no cigar. The C3 image was reduced to an 8 megapixel image to match the field of view and it isn't quite there. So perhaps 16 megapixel is a bit of an overkill, at least as far as resolution goes....Show more →
Note though that the NEX is also limited by an AA filter which the M9 is not and that makes a difference.
Well, we seem to be in agreement. 
