Lunch atop a (Springfield) skyscraper

Lunch atop a (Springfield) skyscraper
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2

I think you are seeing strong chromatic aberrations. Those come from different colors of light getting refracted slightly differently, so the focus points for the different colors are in different positions. The result is typically that parts of the shot off-center (and not necessarily out of focus) have purple and/or green halos. Green halos would not pop ...


2

I had the same problem with the EF 75-300 lens. I found out that the optics in the glass is made poorly and has a really bad drop off around the edges and when its out of focus the poor contrast on the images. I sold the lens for almost the price I paid for it and saved up for the EF 70-200 f2.8 II USM. Even the EF 70-200 f4 hands down better. The Price ...


6

There's nothing obviously wrong with the image. You've got a very narrow depth of field, so the grass in the foreground and background is out of focus, but that's not surprising if you were shooting something relatively close at a long focal length. There's some chromatic aberration (red and purple fringing) in the unfocused areas, which also isn't ...


2

What you're seeing is know as bad bokeh. What's bokeh? It's a term that describes the quality of the out of focus areas in an image. What is good bokeh and what is bad bokeh? Umm... if you like the look of the out of focus areas it's good, if you don't, it's bad. That being said, characteristics of good bokeh include circular highlights with no "edge" to ...


1

if it is possible to view a number of scenes stereographically after the lens distortion is removed from them Yes. In theory all distortion correction does is undo some distortion a lens introduces because it is not an ideal ( theoretcally perfect ) lens. You will note this distortion is radially symmetrical and the effect is most notable in the ...


5

No, these are unrelated. Distortion removal is a 2D mapping which moves pixels to remove barrel and pincushion distortion. Parallax correction requires multiple images or depth information for each pixel and is performed by completely different software algorithms.


10

Does anyone know if this software uses the Brown-Conrady model to achieve the lens correction? Yes they do use those very common camera calibration coefficients. I added some copyable text versions of the formulas to the following quote: Adobe Camera Model Geometric Distortion Model for Rectilinear Lenses xd = (1 + k1*r^2 + k2*r^4 + ...


3

I can't speak specifically about LR, but many raw processing applications don't use one of several generic mathematical models (such as Brown-Conrady) that are based on an assumption of rotational symmetry at all if the lens used is a fairly popular one. Instead they use a calibrated correction profile to correct for the measured distortion of the lens at ...



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