@Piet_du_Preez Welcome to the forum!
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Sharpness is a function of contrast.
Once you grok that, this whole thread - including the initial post - becomes mostly moot and everyone would be talking about conceptual and creative usage of contrast. Most of that would be through lighting and gradients and falloff and edges and whatnot.
Still, the algorithms to detoriate the image from the original RAW file even more are needed. Someone having spent the better part of the last years on exactly those algorithms should know better. Photography is the transformation of light into something else. It is never about reality but only about the remembrance of a possible perception of a moment in space and time. Another hard concept to grok.
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This does not necessarily have to be the case. When you lose sharpness, you first lose the contrast at the edges before you lose detail. Thus, if you restore the contrast on the edges that must not mean that you add something that was not there.
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@Thomas_Do you’re not adding the same thing that was lost though - only something that attempts to reconstruct the appearance of it — which is fine but it’s no the same thing.
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The ‘loss’ is not binary though.
‘Lost’ detail can mean that high-frequency detail is just underrepresented (as in: has the wrong ratio to low-frequency detail). Sharpening is not necessarily trying to reinvent lost information from thin air, it tries to guess what the true relationship is based on existing/captured information.
Superresolution techniques tries to reasonably ‘Invent’ lost Information. Big difference.
(Sharpening and SR-tech can have overlap…deconvolution touches both fields imho)
Yes, not the same thing. That’s why people searching for algorithms to generate results as similar as possible. The point is, applying a little sharpening might bring the appearence of the image closer to “reality” than doing without sharpening altogether.
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good point - guess we have to be clearer on whether we’re talking about boosting existing information or trying to recreate it.
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But the difference seems like mostly a moral one and that moral distinction is only relevant to a few niches of photography.
Actual “true” representation and believable truth in image are different things. The former doesn’t exist you can only be closer or further from it. Which leaves us only with the artistic judgements. Believable truth can be a goal but it has to be interpreted and selected . Created.
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That’s why I put resize sharpening in a separate category - down-resizing is a gross loss of information in the first place, so putting in a bit of sharpening afterward to enhance acutance doesn’t seem so egregious…
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Most mobile phones have that resolution. By referring to 1080p resolution did you mean low DPI actually?
i mean displays with ways less resolution then your camera captures viewed from shorter distance. if you look at your expensive 45+MP cameras output scaled to fit even your mobile phone display you’ll be disappointed without sharpening.
low dpi is quite uncritical, most large size posters are low dpi but viewed from quite larger a distance … it’s primarily the distance you’re viewing at an image.