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Nick Karagiaouroglou
{K:127263} 4/14/2008
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Zzzzactly, Andre! You just covered exactly as scientific one *very* main part of it, which goes back to the fact that the scanner doesn't know what distance it should focus on. A great example, that you gave, and I must take that into my notices about that!
For imagine the poor scanner "seeing" too lines. One is formed by the tips of those tiny "mountains" of the matt finish, the other by the pixels of something that was really captured. What should the poor machine choose? Though we, as human beings, are immediately able to recognize what was the depicted subject of the image, and immediately focus appropriately, it is such a hell of a work - and sometimes also imposiible - to express what we exactly do for recognizing the right pattern, and translate that to some programming language for making the software.
In this sense, perhaps a good thing would be to allow the user of such a scanner to directly see on the screen what the scanner "sees", and adjust a slightly different focus that falls on the plain of the real image rather than in the "plain of the tips of those "mountains". That should be already feasible with the available technology, I guess.
Cheers,
Nick
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Andre Denis
{K:66327} 4/13/2008
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Hi Nick,
What you say makes perfect sense about the matt print scans sort of distorting because of the texture. If you take it many steps further and scan some 3D objects like flowers or even a face, the distortion is many times greater. This makes for some interesting fun images, almost like reflections in disturbed water.
Now I know the scientific explanation for it :)
Andre
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Nick Karagiaouroglou
{K:127263} 4/13/2008
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Thanks a lot for the info on the word, Andre! Must remember that, matt finish!
Indeed one should expect more grain/noise in the low lights when using higher speed films. More sensitivity simply costs smoothness. But it can also raise contrast, so it's another nice subject to deal with a bit more.
About scanning, I've found some more info in photography books since it really wondered me. Unfortunately for me, though I consider a photo with a matt finish better to look at (it doesn't have so strong reflections), it is not as good for scanning. The higher resolution of the scanner does regognize the tiny details of textures exactly as any other detail on the image. Now, when the adjusted scan resolution is at the same resolution of that tiny texture, there is what is called "resonance", and in this case it is unwishable, since the scan of the pixels of the image is exactly at the same size order as the scan of those tiny texture elements. And the scanner gets "frustrated" because it can't tell the details of the image from the details of the texture. They also say that in such cases the best option is to choose a scanning resolution that is high enough *and* not an integer multiple of the resolution of the texture of the finish.
So much to learn and wonder about.
Nick
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Andre Denis
{K:66327} 4/12/2008
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Hi Nick,
Yes, we call it matt finish too. That's an interesting point about scanning matt finished prints. I would guess that the nature of the textured, duller surface will be more like a low light image than a shiney gloss surface, even though the image comes from the same camera, negative and settings. Certainly, the higher the film speed setting and the higher the film speed for use in low light conditions, the grainier or noisier the image will be.
Andre
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Nick Karagiaouroglou
{K:127263} 4/3/2008
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Hi Andre!
And many thanks for all the good info! I pretty soon also realized that quick scans are no good scans, and so I go for rather high scanning resolutions and bigger sizes when I am scanning. It takes more time but it minimizes the errors due to scanning, and so I have a file that can be downsized for posting etc. But most of the time I get also a CD of the images together with the prints from the processing company. And most of the time the images on CD are better than my scans.
This whole series is from such a CD. So it must have been only the way I shot the photo. And while low light is indeed always good for such a noise/grain, I get more and more the feeling that this gets enhanced by the a softer focus too. And this exactly is what I can't understand. Or perhaps it is only my impression?
BTW, about scanning again. Some certain higher resolutions can be tricky too. When I scan for a 30x20cm file from prints that are not glossy (What's the opposite of glossy? We say "matt" in German. :-/) then the scan is of middle-low quality at 180dpi, it gets completely terrible and full of jigging effects at 300dpi, then again middle-high quality at 450dpi, again terrible at 600dpi, and finaly high-quality at 1200dpi. I think that this is because of the coinciding resolutions of the scan and the physical texture of the "matt" surface of the print. I guess that all the tiny "bumps" and "peaks" of the non-glossy surface are also somewhere near 300dpi and so they interfere with the scan - but I might be also completely mistaken. Anyway, I don't know how to circumvent that. Any idea?
Cheers!
Nick
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Andre Denis
{K:66327} 4/1/2008
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Hi Nick,
I think it's a fairly common thing with low light conditions. I found when scanning some old colour prints, the situation seems to be even more visible when I enlarge a print digitally. I made a big mistake a few years back when I first started scanning old images. My computer was very slow and I got impatient with the time it would take to scan the images. So, I scanned hundreds of them much too small to be of any use. When I view most of those images on my computer screen they are quite poor quality. The ones that I took my time with and scanned into larger files came out much better.
Are your images scanned from prints or negatives. Or do you get them put on a CD from the company that does the processing? Before I bought my digital camera, I had a lot of rolls of film put directly onto CDs at the same time as the negatives were developed. The files of each print were huge when I had them done that way.
Andre
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M jalili
{K:69009} 3/30/2008
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Thank you very much my dear . All regards .............
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Nick Karagiaouroglou
{K:127263} 3/30/2008
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Thanks a lot again for the nice comment, and even more for your observing eye, Andre! I was really wondering why nobody up to now referred to that noise/grain/whatever. But I should have known that nothing escapes your eye! ;-)
If I am not completely mistaken, I think that I have observed some kind of dependence between such a noise and what I do on the camera. (At least T70 and T90) Under low light conditions in combination with just a bit softer focus, such a noise always seems to appear. What can that be? I like it many times but I don't have a clue at all, why it should appear.
If it appeared on all underexposed regions I would say that this is perhaps the result of too little light for a uniform consistent burning on that region of the film, but then why does it appear especially when using soft focus? I don't get it a bit at all, though I already use it so often.
Anybody any ideas?
Nick
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Nick Karagiaouroglou
{K:127263} 3/30/2008
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Oh no, no, please don't be sorry for that, Yazeed!
I just think about how much inflation of ratings we can stand! It seems that ratings start at 7 and go all the way up to infinity! ;-)
Cheers!
Nick
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Nick Karagiaouroglou
{K:127263} 3/30/2008
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Thank you very much again, Gustavo!
Nick
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Andre Denis
{K:66327} 3/29/2008
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This is a very lovely Tuscany image Nick. The image is a little noisy, but it doesn't distract too much. If anything it seems to add to the atmosphere. Even the electric wires seem to be arranged with artistic style in Tuscany :)
Andre
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M jalili
{K:69009} 3/29/2008
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In fact when I see the work is very beautiful pride myself in that I put a sign Evaluation. I am sorry .
Yours Yazeed
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Gustavo Scheverin
{K:164501} 3/29/2008
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Muy bonita, simpe, elegante y muy bien compuesta.
Felicitaciones!
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Nick Karagiaouroglou
{K:127263} 3/29/2008
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Thanks a lot for the generous comment, Julie!
Cheers!
Nick
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Nick Karagiaouroglou
{K:127263} 3/29/2008
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Many many thanks for the enthousiastic comment and the hyper-generous rating, Yazeed! (A normal 7 is already enough ;-))
Cheers!
Nick
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Julie Salles
{K:22654} 3/28/2008
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Absolutely wonderful Nick!
Best,
Julie.
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M jalili
{K:69009} 3/28/2008
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Woow wow . 7++++++++++++++
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