Film vs digital: image texture and the rendition of edges ...

droj

droj

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A photograph even in its very texture is more than a technical accomplishment - it has certain qualities that accord (or don't accord) with the human heart and a sense of naturalness.

In this regard, I can't help noticing that in many images that are wholly digitally produced, there's an awkwardness about 'edges'. What edges, you may ask? Say that there's a 'subject', and it's largely in focus. And that there's a background that's less in focus. The edge I'm talking of is the one that separates those two zones. There are many examples in these very forums.

In many a digital photo, the 'subject' looks uncomfortably as if it's a cut-out that's been pasted in (even when it patently hasn't been).

I've never been aware of this effect with film, even film that's been scanned and its image digitally processed. It's as if the engineering has gone too far. But I haven't got a clear sense of when it happens and why, though it may be a result of lots of pixels coupled with aggressive firmware / software processing defaults?
 
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or maybe the way the image has been sharpened ?

i notice the almost super imposed effect on some of my own images of birds with a bland background especially if iv'e been a little to keen with the sharpening tool
 
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Most digital photo's are taken with shorter lenses, in front of smaller 'capture' frames; as the focal length increases, so the nearest focal distance increases, as does the range of variable focus before infinity, as that too travels further from the camera.
Consequently, near to far Depth of Focus 'Sharpness', for the same framing of a subject would tend to increase, but the flip side is that when DoF is reduced in selective focus, the transition from sharp to soft, is over a much shorter range, hence will appear that much harsher...
But yes, I agree, was thinking similar about a shot I took a few months back, where my daughter & g/f look like they have been photo-shopped into the back-ground!
 
A lot of folk seem to think they absolutely must shoot their fancy lenses wide open to get the "pop", maybe that contributes?

But a lot of film shot these days is with much older cameras and lenses (mine are from the 1970s), and I guess contrast and acuity (?) are lower than modern lenses; OTOH transitions and mid tones seem to work better. I see this particularly with black and white; I do enjoy the Black and White thread here, but a proportion of the shots are just weird, way overdone "conversions".
 
I'd put it down to the 2D nature of digital rather than the 3D of film - there's more scope for "image bleed" in a 3D film emulsion. Plus the wonderful unsharp mask which works by accentuating edge differences.

I looked at the edges of a couple of my tree photos, one from a Sony a7r with a 1970s/1980s OM lens and the other from a 5x4 negative taken with a 1950s Schneider lens and couldn't see much difference when both were viewed at the same screen size (meaning 100% with the digital, and much less for the 5x4). The 5x4 was the straight scan, with no sharpening.
 
droj said:
In many a digital photo, the 'subject' looks uncomfortably as if it's a cut-out that's been pasted in (even when it patently hasn't been).
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I have also noticed this. And I don't think it's sharpening.
 
I put a lot of it down to much messing around in pp,to me it seem that every shot must be pp out of existed so it no longer looks natural (n)
 
simonblue said:
I put a lot of it down to much messing around in pp,to me it seem that every shot must be pp out of existed so it no longer looks natural (n)
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I've noticed it on certain shots of mine that've had pretty limited intervention apart from the basic RAW import functions.
StephenM said:
I'd put it down to the 2D nature of digital rather than the 3D of film - there's more scope for "image bleed" in a 3D film emulsion. Plus the wonderful unsharp mask which works by accentuating edge differences.
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This sounds something like it ...
 
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An effect which is very popular today is something called "3D pop", where the background is slightly and smoothly blurred, and the subject seems to float in front of it with the background seeming really further away. The effect depends critically on acute sharpness of the edge of the subject adjacent to the background. This can be seen on large images which have that "3D pop" when viewed at screen size (i.e. reduced in size), but the effect disappears when you look at the original image size because the edge has become softer when magnified. Accurate focus, good sharpening, and a really good lens are required to keep the effect up to the original image size.

If a comparison of my old 35mm film SLR photographs with today's digital ones is any guide, the effect happens much less often on film because the lenses aren't as sharp, the focus isn't as accurate, and the only sharpening was mild and due to bleed of exhaustion of developer across wide light/dark transitions. If you don't like the effect it's easy to make it look like the film image just by means of a slight amount of gaussian blur. If you don't post process your images and don't want the effect in your ex-camera jpegs, just turn down the sharpening until it goes away. Nothing to do with any special difference between analogue and digital, just an effect which is now popular, and easier to get with digital if you want it. If the effect is exaggerated (which it often is by clumsy enthusiasts) it can look oddly unnatural. Closer examination will reveal digital sharpening artefacts.

You don't get digital sharpening artefacts in film. But you can get film over-sharpening artefacts. Solarisation is a well known example (and does involve more than just edge sharpening).
 
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Yeah Rog, your lenses are crap, your focusing off and digital can replicate the film "look" with gaussian blur.......:ROFLMAO:
 
droj said:
In many a digital photo, the 'subject' looks uncomfortably as if it's a cut-out that's been pasted in (even when it patently hasn't been).
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That's because most people don't know how to correctly handle their images in post-production, or are over sharpening them. It's the curse of amateur (and a great deal of professional) digital photography: People just don't know when to stop. It's like when a 17 year old decides to "modify" their car... but worse because it's all over the internet.

There's no reason why edges should look any different on a digital image, assuming there's enough resolution to avoid obvious aliasing.

Either that, or you're talking about something I've never noticed.
 
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Pookeyhead said:
That's because most people don't know how to correctly handle their images in post-production, or are over sharpening them. It's the curse of amateur (and a great deal of professional) digital photography: People just don't know when to stop.
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Yes, this is prevalent, but not all of what I meant ...
Pookeyhead said:
There's no reason why edges should look any different on a digital image, assuming there's enough resolution to avoid obvious aliasing.
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Maybe the structure of film grain comes into it? (See Stephen's post 5 above).
 
chris malcolm said:
If a comparison of my old 35mm film SLR photographs with today's digital ones is any guide, the effect happens much less often on film because the lenses aren't as sharp, the focus isn't as accurate, and the only sharpening was mild and due to bleed of exhaustion of developer across wide light/dark transitions.
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StephenM said:
I looked at the edges of a couple of my tree photos, one from a Sony a7r with a 1970s/1980s OM lens and the other from a 5x4 negative taken with a 1950s Schneider lens and couldn't see much difference when both were viewed at the same screen size (meaning 100% with the digital, and much less for the 5x4). The 5x4 was the straight scan, with no sharpening.
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Even if there is any genuine difference in the first place., like StephenM, I can attest that my 70s and 80s FD, C/Y and OM lenses are perfectly sharp when used on modern digital cameras (a 24 Mpx Sony A7, 12 Mpx 5Dc and a 12 Mpx 2x crop Panasonic G2) so I think that particular hypothesis can be ruled out.

Besides, the optical formula for a number of Canon's FD lenses remained exactly the same with the transition to autofocus are are still for sale today and I'm sure there are any number of Nikon shooters using older lenses on their digital bodies.
 
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I don't think it's anything to do with lenses.
 
droj said:
I don't think it's anything to do with lenses.
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Can you post a hi-res image of what you mean? Post up a full res example of one you feel suffers from the edge issue.

I read post #5.. I can't see it being that somehow. I certainly haven't noticed anything like that on my own images.
 
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Pookeyhead said:
Can you post a hi-res image of what you mean? Post up a full res example of one you feel suffers from the edge issue.
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Nothing to hand at the moment, sorry David.

It's only guesswork, but essentially I feel that it's connected with rendering ... film grain having a more random disposition than pixels being at the root of it. I might compare it with a difference between vinyl and cd ...
 
It will be down to some clever science, but its just as simple as this. Two different tools for a job.

Just like each film has a look, MF has a look, so does digital, in fact each brand has a look.

That's whats amazing about photography, the variety.
 
Maybe you're right. All I know is, that image I posted above, when viewed at 100% is equal to a print around 1.5 metres wide by nearly 3 metres tall, so if you need to zoom in more than 100% to see whatever the artefact in question is, it's irrelevant. Stop pixel peeping :)
 
No pixel peeping here - the effect(s) I'm on about can be visible across various magnifications - it's not to do with size!
 
The only other thing I can fall back on is the "all or nothing" of digital. It either resolves or it fails - no graceful fall off like film. A lens test chart will show a sudden switch from resolve to grey mush, whereas film will gradually tail off.

Edit to add: the only difference I see is that digital at 100% looks clean, and a film scan (at the size I scan) at 100% shows blur. Given Ctein's comments on visual accuity to the effect that how sharp something looks depends on the resolution at 30 lppm, this may have a bearing.
 
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droj said:
No pixel peeping here - the effect(s) I'm on about can be visible across various magnifications - it's not to do with size!
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Still baffled. I'd like to see an image you feel suffers from this artefact. Maybe I'm being thick, but if it's something you can see at even low resolutions, it must be fairly obvious.
 
droj said:
No pixel peeping here - the effect(s) I'm on about can be visible across various magnifications - it's not to do with size!
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If it is so obvious to you then surely it is easy to post some examples of what you actually mean...
 
dejongj said:
If it is so obvious to you then surely it is easy to post some examples of what you actually mean...
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+1 I'd like to see what he means.
 
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