Am I oversharpening
in [Digital Cameras]
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From: Bart van der Wolf on 5 Jun 2005 08:00 <george_preddy(a)yahoo.com> wrote in message news:1117934606.605577.297030(a)g47g2000cwa.googlegroups.com... SNIP > Bayer DSLRs are characteristically blurry and soft because the true > optical resolution is the resolution of each, individual, tiny, > subdivided, R, G, or B exposure, [...] How typical, only half-truths (if any). Did you forget about lens quality and the anti-aliasing filter, which are the true source for blur? Resolution is limited by that, the sampling density, and output magnification. Bart
From: Big Bill on 5 Jun 2005 09:49 On 4 Jun 2005 18:23:26 -0700, george_preddy(a)yahoo.com wrote: >> >There is absolutely no reason why the three color samples have to be >> >taken at the same 2D location. > >The point is they have to be taken. Bayer hardly takes any color >samples given their phony monochrome MP ratings. Listing monochrome >MPs is a scam. There are NO WHERE NEAR enough color samples taken with >a Bayer sensor to support the advertised color MPs. You *do* understand, don't you, that the Foveon sensor only samples monochrome light, right? It's an inherent characteristic of today's photo sensors used in consumer cameras.The concept that Foveon somehow managed to capture color where everyone else captures only monochrome is wrong. Foveon measures luminance as filtered by the silicon, whereas Bayer filtered sensors use a Bayer filter. Each then asigns color according to where each sensor is located. If you didn't know that, you do know. So Foveon sensors have no inherent superiority or even ability to capture olor. All color is asigned by the firmware in the camera. What differs is *where* the filtering is done. -- Big Bill Replace "g" with "a"
From: Big Bill on 5 Jun 2005 09:50 On 4 Jun 2005 18:23:26 -0700, george_preddy(a)yahoo.com wrote: >Interpolation never adds optical resolution. Exactly. That's why somany are saying the Sigma SDx cameras are 3.43MP cameras; the 10+MP figure is arrived at through interpolation. -- Big Bill Replace "g" with "a"
From: george_preddy on 5 Jun 2005 15:12 C Wright wrote: > On 5/30/05 3:42 PM, in article > 1117485741.612985.156090(a)o13g2000cwo.googlegroups.com, > "george_preddy(a)yahoo.com" <george_preddy(a)yahoo.com> wrote: > > > > > > My point stands. Digital sharpening ruins images because it plows > > through every pixel blindly, instead of leaving sharpness/blur to > > optics. That is why film lovers hate digital, the result is flat and > > lifeless, often even inverted. > > > > If you sharpnen digitally, you are simply exceeding the capabilites of > > your camera at the expense of quality. The only proper way to handle > > digital images that are breaking down is to print them at the size they > > were intended. There are no acceptable algorithmic crutches that can > > substitute for sensor count. > > > George (if that is your name) you are a piece of work! Any digital > sharpening that I have done does not plow through every pixel blindly. > Sharpening that I am familiar with is adjustable according to threshold, > radius and degree or amount. That has nothing to do with lens optics that should produce blur in some places and sharpness in others. > Millions of images taken by thousands of > digital photographers, and sharpened digitally, disprove your assertion that > they are all exceeding the capabilities of their cameras at the expense of > quality. No it doesn't. Digital has a very bad reputation among no-comprimise photographers, because the overwhelming majority of people who use digital don't understand that their Bayers take 3 very small RGB exposures, then combine them while upscaling by 400%. The upscaling makes the pics blurry and flat. Artifically sharpening from top to bottom, without regard to optics may make some of the edges arbitrarily sharper, but flattens the overall image even more, or may even perceptually invert parts of it. It is no coincidence digital is criticized by serious photographers and clients--even if they don't understand why, they know a flat, lifeless, low resolution image when the see it.
From: george_preddy on 5 Jun 2005 15:51
Bart van der Wolf wrote: > It was already clear that you don't understand the difference between > monochrome (single color), and spectral band. Each sensel is natively > sensitive to a spectrum of roughly 350 to 1000 nm, and filters > restrict that to 3 (sometimes 4) slightly overlapping spectral bands. Oh, and I thought monchrome sensors always produced a big solid 1 color rectangle. |