Skipping the Low Pass Filter: What am I Missing?

astrosecret

Recovering rollei snob
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I'm trying to figure out what removing the moire filter does for image quality. Moire happens when minutia is so fine that the camera's sensor cannot resolve the information. Anti aliasing filters blur the image precisely to the point where the sensor is able to resolve such fine detail. So all you're losing is the resolution that wouldn't be there anyway, nothing more. So actually, you're not gaining or losing anything. at least that is what i understand low pass filters to do. Where am I wrong and how does this actually make the sensor perform any better than a full frame sensor? it sounds to me like marketing bs.

The bayer pattern is not random either, it's just different. so? still the same amount of RGB pixels. more marketing bologna?
 
Well, not exactly. A low pass filter is required due to sampling theory. If detail exists at spatial frequencies greater than can be sampled by the sensor (determined by it's pitch and pattern) then that detail will produce false patterns (due to aliasing ie foldback of higher spatial frequencies into lower ones).

The semi-random non-bayer pattern of the PRO may make this aliasing less noticable or more pleasing perhaps.
 
Fujifilm's approach with the XP1 is an interesting attempt to overcome a fundimental problem with Bayer sensor imaging. Hopefully this new system will lead to other RGB micro lens schemes.

Filters, both physical and virtual, are commonplace when digital and analog data is recorded. All filters degrade the original data. The loss of useful information destroyed by the filter is offset by the attenuation of artifacts and in some cases by smoothing noise. The selection of an appropriate filter is a compromise and flexibility in filter choice is important.

A well-designed filter is not necessarily a bad thing. In digital photography the AA filter is part of the sensor assembly and unfortunately one filter must be used for every subject. This means sometimes the AA filter can do more harm than good.

AA filters were too strong in the early years of digital photography. More recently cameras have filters that are better matched to the sensor. The X100 has a weak AA filter for instance. Because the M8, M9 and very expensive medium format digital cameras do not use AA filters, people associate the absence of AA filters with quality.

It will be interesting to see how the D800E is viewed a couple of years from now.
 
Removing the filter MUST be important, because Nikon just announced that a modified D800 (called D800E) will be offered without moire filter! And they're charging an extra $300 for the priviledge of owning one of these un-filtered babies! Now Nikon wouldn't charge $300 for nothing, would they? Would they?? Hmmm... :)
 
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