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9

Aliasing is the result of repeating patterns of roughly the same frequency interfering with each other in an undesirable manner. In the case of photography, the higher frequencies of the image projected by the lens onto the sensor creates and interference pattern (moiré in this case) with the pixel grid. This interference only occurs when those frequencies ...


8

The D800E doesn't have an optical low-pass filter (LPF). The filter sits on the chip before the photosensitive diodes. I suspect the D800E is more expensive because of lower volume for the camera (think an order of magnitude lower), maybe it is also more expensive because it speaks to very specialised users, and maybe even as a deterrent. The D800E will ...


8

A traditional AA filter consists of two parts, one splits the image horizontally with a ~1 pixel offset (effectively giving one image superimposed on itself with a very small horizontal offset). Behind this is a second filter that does the same vertically. The effect of this is to split each light ray four ways so some of it lands on each of the four RGGB ...


8

Aliasing means quite a few different things. They're all generally related (effects from digital sampling) but in different situations, it takes considerably different forms. For example, even though they're both digital graphics, what you see with a digital camera is considerably different than what you see in computer generated graphics (and both are ...


6

You can't get the same effect in software. You can get somewhere nearby, given certain assumptions. But the AA filter spreads light so that it strikes multiple different coloured pixels giving you information that is absent from the no-AA filter sensor. The Nikon D800E doesn't do anything at all to try and replicate the AA filter. If there are high ...


6

Aliasing is characterised by "jagged" diagonal lines. If you try to draw a diagonal line on a pixelated image where each pixel can be only either black or white it will appear stepped or jagged, as in this very bad example: ---- ---- ---- So if you have hard edge in a digital image you will get this effect regardless of the number of colours ...


5

The physics simply doesn't work that way. Aliasing irreversibly transforms frequencies past the Nyquist limit to appear as frequencies below the limit, although those "aliases" aren't really there. No amount of processing a aliased signal can recover the original signal in the general case. The fancy mathematical explanations are rather long to get into ...


5

In contrast to the standard 2x2 bayer pattern the X-Pro 1's sensor uses a 6x6 pattern (see this link for images) R,G,R,G,R,G G,B,G,G,R,G G,B,G,B,G,B R,G,R,B,G,B R,G,R,G,R,G G,B,G,G,R,G G,B,G,B,G,B G,R,G,G,B,G R,G,R,G,R,G B,G,B,R,G,R G,B,G,B,G,B G,R,G,G,B,G The new pattern results in every horizontal and vertical ...


4

There are much smaller cameras without anti-alias filters. The Olympus PEN E-PL5 uses a 4/3 sensor and the Fuji X20 uses a 12 megapixels 2/3" sensor which is only slightly larger than sensors of compact cameras and even lower resolution. What is seems like to me - and I am speculating - is that most digital cameras had anti-alias filters because everyone ...


4

To increase sharpness you get better results going to a larger frame. The technology advances in micro steps, mostly seeking to reduce power, increase light sensitivity, and rolling out few changes in features that could have been activated from the start, but strategically held back, just so they can get people to buy more cameras for those features. Pixel ...


4

The higher-resolution is certainly going to make things sharper for one camera :) Even when scaled down, this still shows since the downscaled image of one camera is generated with much more data. Differences between anti-alias filters are minuscule, so you can ignore them unless all else was equal, meaning you had a K-5 IIs and K-5 II or D800E and D800 ...


4

The effect of omitting the low pass filter decreases as resolution increases. That's why we're suddenly seeing AA filterless cameras, we've reached a point where aliasing is no longer a significant problem. The difference you see will depend on what glass you're using, really sharp lenses will still produce aliasing, at least in the centre. In most cases ...


3

It is because pixel density compared to lens resolving power has increased to the point where aliasing occurs less frequently and users are becoming increasingly demanding when it comes to resolution. AA filters are there to prevent aliasing. Aliasing is worse when the signal frequency is very close to the sampling frequency. If you increase sampling ...


3

I'd be surprised if you saw a difference. Remember, the image has to go through a re-sizing algorithm that would cause the slight difference between an AA image and non-AA image to disappear.


3

If the use of a second filter to reverse the effect of the first arises from the problem that entirely removing the AA filter would change the plane of focus, why not just do that, and calibrate the AF system in the camera accordingly? Adjusting the AF system calibration does not fix the focus offset for manual focus. You would have to adjust the ...


3

The answer is in the quoted article. "We know that the full low-pass filter cannot be completely removed, because it would cause the focal plane to move; plus, the camera still needs to be able to reflect infrared light rays." Manufacturing concerns, as pointed out by rfusca probably have some contribution, but you still need to have the 3 filters ...


2

What you're seeing is most likely the result of variability in the experimental conditions. Almost all the DXO mark scores relate to noise in some way. Dynamic range is measured by finding the difference in illumination between the saturation and the point where the signal to noise ratio drops to 1. The colour sensitivity score is the logarithm of the ...


2

The best way to find out if a cell phone is using an anti-aliasing filter is to ask the manufacture. There is no way to control it. The filter is a physical object, not a program. It sits in front of the sensor. That being said, I would guess that there is no AA filter because of the small size of the pixels. But that's just a guess. Someone who knows for ...


1

Not as of 2013. Canon is a bit late to the game. Nikon, Olympus, Pentax, and Fuji for example make various cameras without optical low-pass filters. It is quite a new development for a variety of reasons, most of which have been covered in existing questions/answers on this site. Take a look at: Why only recently are digital cameras being sold without ...


1

When talking about aliasing, pixel pitch is much more important than overall resolution. For the most part, the newer cameras without AA filters have pixels that are approaching a size smaller than details the lenses used on them have the ability to resolve. Pixel size for the 36MP D800 is 4.84µm. The smaller sensor of the 16MP Pentax K-5IIs and the Nikon ...


1

These are all good answers and good information. I have a very much simplified explanation. Let's go from 2D to 1D (same concept applies). When a frequency hits your sensor that is higher than the "max allowed frequency", it will actually create a mirror frequency into the lower side. Once your image has been sampled you will see this lower signal but the ...


1

As @ElendilTheTall suggested this question isn't really about photography, however I guess if you were making an app to scale photographs in a phone or such it isn't really that miss placed. The wiki about anti-aliasing has a lot of information, I believe it explains what your are looking for. From memory I seem to recall this is about the number of ...


1

The chance of moire with the D800E is very low, because of the pixel density. Maybe it could be a problem with fashion photography with very fine structure smaller then the pixel density of the Nikon D800E. So I'll go for the little bit more expensive D800E and I will be curious to see what the difference will be with the Leica S2



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