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MystyrMystyry
05-21-2011, 10:47 PM
There's been this tedious debate going on about the relative quality of digital sensors vs film (slide and negative) ever since the first digital cameras hit the shelves back in the nineteen nineties

The fact that they don't exactly compare seems to be missed on people who seek a definitive answer (there's a new one born every minute) and they just can't grasp the point about pixels (picture elements) not relating to film grain (organic visual noise)

Are 8 (or 10, or 12, or 14, or 16, or 18...) megapixels sufficient to replicate the smoothness of fine grain 35 mm film? This they ask over and over as though it makes an actual real world difference to the subject and execution of the picture

It never occurs to them that because 35mm was, for nearly a century, merely a consumer format (which happened to be used by professionals due to its omnipresent availability and therefore convenience) it was basically pretty bad quality due to its tiny size, and though far finer grained versions came and went (requiring ludicrously slow shutter speeds beyond the realm of simple hand-holding technique) the graininess became one of the aspects of photography that separated it from other artistic mediums (cinema veritae excluded because to what degree the camera may be purposely 'shaken' is entirely subjective)

Where most artforms seek clarity of both subject matter and representation, art photographers came to use grain (as well as blur, under- and over-exposure, various filters, black and white) as an extension of their self-expression (though rarely as their complete vision)

But curiously concurrent with the rise of digital imaging came print scanners, imaging programs, and the internet for all the after-manipulation any amateur or professional could ever wish for (I had more than two thousand plug-in filters and actions at one stage, which I knew was overblown, but they were there and they were free, so why not?)

But it struck me recently that in this striving for digital clarity the camera makers seem to have overlooked something. Sure they have included any number of effects and filters (simpler versions of standard Photoshop-type versions) but I've yet to see a 'grain' setting

So I designed one of my own - but I'll get to that in a minute

The thing with grain is that it allowed the film image some latitude in detail, that is it could be slightly out of focus or wobbly, but thanks to the grain adding perceived detail these slight defects usually went unnoticed and even undetected

With pixels you can obtain a relatively crisp picture within the confines of light rendering into a digital algorithm (remembering that even 28 megapixels will still be consumer grade photography relative to what the future holds - imagine adjustable filter plug-ins to recreate the 'quaint' quality of early 21st century photography)

So why the need for perceived clarity in photography at all, surely video cameras don't bother with it, shouldn't it be even less of an issue with a still photo?

Yes and no - a video usually involves a lot of movement to disguise the fact that it has limited dynamic range and quite low resolution but a still image requires a lot of detail, even if only in textures, to maintain interest

At this point some shall wish to cite Andy Warhol or Marc Rothko as composing some of the least detailed paintings ever, which is fine, but this isn't about art as much as art photography, which is a slightly different animal through general size constraints and expectations of the medium

Digital sensors are not perfect and do actually interpose a lot of messy digital noise (this is not the same as film grain) into the photo before a filter is applied to remove it, but in so doing, some of the perceived detail is invariably lost along with the 'hot spots'

So what I have done is take a series of high resolution photographs of unspoiled early morning sand (which is both organic and grainy) and by superimposing them over some less than scintillating pictures taken at various settings, created what look like high resolution professional film and slide photos

The effect is not just limited to my own, but to virtually any lo-rez picture downloaded from anywhere on the net

And those in the know shall ask but doesn't Photoshop and similar already have an add-noise filter - why not use that?

Because they look awful, and take an age to get the right settings for what I wanted to create - a meld of digital and organic clarity. We are largely stuck with infant digital and its slow evolution into a mature medium - at least at a consumer level (you can still buy film cameras and film for far less than the outlay of a shiny new digital Nikon or Canon - and you really don't want anything less - but by the time you've taken a hundred shots and had them developed any savings will be moot)

But in closing I urge you to try it - and don't limit yourself to sand - there are textures everywhere, with cracks and no, concrete, flywire, chipped paint, oiled wood, even plastic lawn from a hardware shop

Have fun!

Gilliatt Gurgle
05-22-2011, 02:38 PM
There's been this tedious debate going on about the relative quality of digital sensors vs film (slide and negative) ever since the first digital cameras hit the shelves back in the nineteen nineties...

...But it struck me recently that in this striving for digital clarity the camera makers seem to have overlooked something. Sure they have included any number of effects and filters (simpler versions of standard Photoshop-type versions) but I've yet to see a 'grain' setting

...The thing with grain is that it allowed the film image some latitude in detail, that is it could be slightly out of focus or wobbly, but thanks to the grain adding perceived detail these slight defects usually went unnoticed and even undetected...

...Digital sensors are not perfect and do actually interpose a lot of messy digital noise (this is not the same as film grain) into the photo before a filter is applied to remove it, but in so doing, some of the perceived detail is invariably lost along with the 'hot spots'

So what I have done is take a series of high resolution photographs of unspoiled early morning sand (which is both organic and grainy) and by superimposing them over some less than scintillating pictures taken at various settings, created what look like high resolution professional film and slide photos...

...at least at a consumer level (you can still buy film cameras and film for far less than the outlay of a shiny new digital Nikon or Canon - and you really don't want anything less...

But in closing I urge you to try it - and don't limit yourself to sand - there are textures everywhere, with cracks and no, concrete, flywire, chipped paint, oiled wood, even plastic lawn from a hardware shop

Have fun!

Interesting post. I recently made the leap into digital SLR with a Pentax K-7. I chose the Pentax partly for sentimental reasons, since I have been using a Pentax ME Super (film) since the mid 1980's and for the practical reason, that the new Pentax will accept any lens that fit the older Pentax SLR's. In other words, I get to use my old lenses. Of course, I must use manual mode for the manual lenses.

I suppose I would be guilty of equating "grain" with "noise". Of course with film, sometimes the "grain" may be partly attributed to the generational loss in quality when converting from print or negative to digital and if scanning from a print you may get more texture from a matte print versus a glossy.

I have experimented with the built in digital filters with good results and I am also toying with the manual screw on filters when using the older manual lenses.

You indicate that you have taken a series of photos of sand. Have you already done this or plan to do this? In other words, will we get to see them?
I look forward to seeing them.


.

Propter W.
05-22-2011, 03:06 PM
Very cool, Mr. Mystyry.

I had the chance to study photography, but I didn't take it and instead I learnt all about the wonderful world of printing :Yawn: I've been thinking about picking up photography a lot lately. I'd go analogue, however. Not because of romantic notions of the past but rather because I have access to excellent cameras and all the material one might need for a very decent price. I can always, and probably will, go digital later on and a grain filter, Mr. Mystyry, seems like a very good idea.

MystyrMystyry
05-23-2011, 01:40 AM
Gilliat! I love the ME Super - it's such a classic! I really wanted one for ages, but settled on my Yashica when the elective called for a manual SLR without cheating (still want one though - one day)

I just bought a Nikon s8100 for the complete convenience of a 30 - 300 mm zoom, and also because it's just so portable ('the best picture is the one you take'), and because it records video in full 1080p (with super slo-mo), has built-in hdr, a retina display, unbelievable macro mode, very good low light ability (hardly ever use flash except for fill, because all digitals suffer from clipping issues in the white), and it's just an all round excellent toy (whoops! I of course mean tool!)

And at twelve megapixels it's still pretty much the state of the art (24 mp is only a hundred and fifty percent better - you'd need 48 mp for it to be twice as many (that's 'perceived' better)

I have to work out a way to fit a polariser though - thinking of making a foam insert

Sorry, this is turning into a review...


I'm not uploading the full rez sands because they're just too big, but they look sort of like this, bland and bespeckled, different levels of grain and grey (this is a middle one, much much reduced)

http://i1134.photobucket.com/albums/m605/mystyrmystyry/sand.jpg

Now suppose I take an old out of focus underexposed low rez photo of some watches

http://i1134.photobucket.com/albums/m605/mystyrmystyry/DSCN0033.jpg

and then combine the sand pictured above

http://i1134.photobucket.com/albums/m605/mystyrmystyry/DSCN00332.jpg

That's an extreme example obviously, but I wanted to emphasise the effect, which can be as subtle or more extreme, as you wish

Happy days!


Propter, photography is a great hobby/obsession, and it's never been cheaper or more convenient - the cameras these days can store thousands of pictures, you already have the fully equipped electronic darkroom on your lap, and these modern digital cameras are plenty convenient (just make sure you buy a back-up battery or two, and a stand alone recharge unit before you leave the store so you don't have to go back later)

Actually that's the problem with camera manufacturers keeping costs down for the consumer - often they don't supply everything you'd think they should, but the extra cost isn't exactly highway robbery, and in my case I had a camera that was immediately useable out of the box for weeks before I got around to getting another battery (you can still recharge it from computer usb), which is nice - to have a couple spare for when that rare bird flies into view or the aliens land

MystyrMystyry
05-23-2011, 01:57 PM
Of course being limited to the number of megapixels your camera comes with isn't the end of the road for ultra high definition. It's quite easy (though time consuming, but anything worth doing is) to take a number of pictures - as you may have tried with a panorama - and stitch them together seamlessly in your preferred imaging program

It's very effective and allows you to make a (or 10, or 100) gigapixel exhibition quality 100 x 150" print, or 1000 x 1500", or whatever size and dimensions you like, and the viewer can personally zero in on any area they choose and see the water spiders in the froth at the base of the waterfall with perfect clarity

MystyrMystyry
05-24-2011, 10:27 PM
Why does digital representation of colour look different to the way I see it?

Colour is a phenomenon that exists only in the brain of the observer: an experience caused by the arrival of photons in the eye, and then the signals are interpreted by the snapping of neurons and synapses

Camera manufacturers are given the task of capturing these photons (which have not the property of colour, but wavelength) and then representing them in a way that creates a recognisably similar experience in the human brain. The systems involved in the process aren't the same as the actual physical environment and inevitably distort or modify the original: a colour reproduction can never be the same as the original: the important thing is that the experience created by the reproduction is recognisable

In digital photography the colour of the filters placed on the imaging sensor is the starting point for the creation of colour - these colours are processed in the camera to produce all the other colours needed to produce the final image. This process involves using highly advanced colour processing algorithms which - in high quality products - are designed to reproduce the image colours in a manner which fits the subjective memory of the viewer, who will be observing the result through a certain colour reproduction system (either monitor or print). The colour best to show the differences in the naturally experienced colour and reproduced, are purples

http://i1134.photobucket.com/albums/m605/mystyrmystyry/9820.jpg

The above image displays the visible light spectrum from 400-700nm and also the Ultraviolet and Infrared light spectrums at the far ends of the visible light. Purple doesn't exist in the visible light spectrum - it is generated in the eye (and digitally) from a mixture of blue and red, due to this reproducing purple is subjective, depending entirely upon our perception

More likely to produce differences because of their spectral characteristics, are colours like cobalt blue which have a spectrum going partly into the infrared region - we cannot detect this, therefore we memorise a blue colour consisting of only the cobalt blue spectrum which the eye can see

Both digital sensors and film are more sensitive to the red content of cobalt blue, resulting in the image appearing purple. Though digital cameras have a filter to cut infrared, differences arise between the colour we observe and the reproduction

http://i1134.photobucket.com/albums/m605/mystyrmystyry/spectrum-difference.jpg