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10/04/2005 02:08:51 PM · #51 |
Originally posted by riot:
A ccd or cmos is often sensitive to a higher range of wavelengths than silver halide crystals, reaching well into the ultraviolet... |
Then why don't I need a UV filter on my digital SLR in the mountains? |
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10/04/2005 02:13:00 PM · #52 |
Actually, having just repeated my maths with the 20D's sensor (which is smaller and lower res, but has a tighter pixel pitch), i get sensor element size of 22.5mm / 3504 pixels = 0.0064mm or 0.0000064m... you get a resolution of 3956dpi, which is near as dammit 4000dpi, and i'll bet it completely canes the 4000dpi scan for detail and sharpness.
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10/04/2005 02:13:20 PM · #53 |
Originally posted by thatcloudthere:
Originally posted by riot:
A ccd or cmos is often sensitive to a higher range of wavelengths than silver halide crystals, reaching well into the ultraviolet... |
Then why don't I need a UV filter on my digital SLR in the mountains? |
What do you think your antialiasing filter does? :)
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10/04/2005 02:16:29 PM · #54 |
Originally posted by riot:
Originally posted by thatcloudthere:
Originally posted by riot:
A ccd or cmos is often sensitive to a higher range of wavelengths than silver halide crystals, reaching well into the ultraviolet... |
Then why don't I need a UV filter on my digital SLR in the mountains? |
What do you think your antialiasing filter does? :) |
Prevent aliasing of my digital images?
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10/04/2005 02:21:19 PM · #55 |
Originally posted by riot:
[quote=dahkota]And, the color palette is unlimited in film where it is limited (though not noticibly for most applications) in digital. |
Not at all. A ccd or cmos is often sensitive to a higher range of wavelengths than silver halide crystals, reaching well into the ultraviolet and infrared if left unfiltered. In terms of colour separation, colour film has emulsions that split it into red, green and blue segments - thus each portion of the film (microscopically speaking) can be full-red, full-green, full-blue or any combination of the three.
In comparison (although ccd and cmos elements are generally larger than silver halide crystals in normal film), each pixel on a digital image is composed of three sensors (like the emulsion), with coloured filters - a red, a green and a blue. Except that each of the three sensors can have values between 0 and 255 (assuming only 8bit output), rather than just being off or on.
I think hes referring to the bit depth. A digital camera ca only capture in 12 bit, where film is much higher. I've constantly said that my pentax 67 velvia slides scanned in @ 4000 dpi produce a better file than what I see from digital. I haven't compared it to the 1ds Mark II, but I did compare it to a 1Ds. Not to mention that nice film look that my prints have over digital. For the studio, I wouldn't use anything but digital.
Off the subject a little, but anybody notice in the Photoshop CS2 that they have incorporated a 32 bit color mode?
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10/04/2005 02:24:26 PM · #56 |
Riot, I quickly did some googling and am getting conflicting information regarding the sensitivity to UV on digital sensors.
Let me know what you find.... |
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10/04/2005 02:29:09 PM · #57 |
Originally posted by MeThoS:
Originally posted by riot:
Originally posted by dahkota:
And, the color palette is unlimited in film where it is limited (though not noticibly for most applications) in digital. |
Not at all. A ccd or cmos is often sensitive to a higher range of wavelengths than silver halide crystals, reaching well into the ultraviolet and infrared if left unfiltered. In terms of colour separation, colour film has emulsions that split it into red, green and blue segments - thus each portion of the film (microscopically speaking) can be full-red, full-green, full-blue or any combination of the three.
In comparison (although ccd and cmos elements are generally larger than silver halide crystals in normal film), each pixel on a digital image is composed of three sensors (like the emulsion), with coloured filters - a red, a green and a blue. Except that each of the three sensors can have values between 0 and 255 (assuming only 8bit output), rather than just being off or on.
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I think hes referring to the bit depth. A digital camera ca only capture in 12 bit, where film is much higher. I've constantly said that my pentax 67 velvia slides scanned in @ 4000 dpi produce a better file than what I see from digital. I haven't compared it to the 1ds Mark II, but I did compare it to a 1Ds. Not to mention that nice film look that my prints have over digital. For the studio, I wouldn't use anything but digital.
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I was referring to the bit depth also. My point is, film doesn't magically "have a colour" - red, green and blue grains can be on, or off. That's one bit colour. You can scan that to whatever bit depth you like, but there's a relationship to the resolution in terms of the colour detail you will get - see the link i posted earlier about aliasing. If you are (theoretically) scanning at the full physical resolution of the film, and assuming a PERFECT lens, each of your pixels is going to be either black, red, green, blue, yellow, cyan, magenta or white - no gradations of hue or lightness. Any such gradations are introduced by unsharpness between the film and the scanner's sensor, or more often (at lower resolutions) the sensor seeing lots of grains together.
This is fine, and this is the principle of film after all, but it's a mistake to say it film has a bit depth without considering its resolution in the equation. At a lower resolution, you get more colour detail. At a higher resolution, your colour detail approaches 1 bit. This would take some very hardcore maths to quantify though, and i'm not even going to try.
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10/04/2005 02:31:37 PM · #58 |
Originally posted by thatcloudthere:
Riot, I quickly did some googling and am getting conflicting information regarding the sensitivity to UV on digital sensors.
Let me know what you find.... |
CMOS sensors are often used in industrial and astrophotographic application because of their ability to record UV well, although i THINK it may vary on the actual design of the cmos rather than what you put in front of it. My main point was also a cmos' natural sensitivity to IR, which you need special film for. Also, black and white film has only relatively recently become "panchromatic" - able to record all colours. Assuming no coloured colour filters on the cmos, a cmos is able to record all wavelengths of visible light.
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10/04/2005 02:32:11 PM · #59 |
i think this argument is silly.
comparing prints and numbers blah blah theyll both yield completely professional results, most people wont be able to tell the difference, and the ones that can (photographers usually) aren't going to be the people interested in putting any images they see to commercial use except their own.
I think it all boils down to preference.
I shoot digital when time or access to scanners or cost is an issue..or for the newspaper.
When I've got time and it's lookin to be an important photo, I'll shoot some 6x6 film. I prefer seein a nice chrome on a light table over a digital file on a screen, just looks soooo much cooler. The end output of printing would look pretty similar between the two in most cases.
If I could shoot 4x5 chromes I certainly would. Discounting Ken Rockwell is kinda rubbish...yea he's biased, but also has what I consider to be some amazing shots, with more pop and better colors than most professional websites I look at...dude knows what he's doing.
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10/04/2005 02:45:06 PM · #60 |
Originally posted by riot:
Originally posted by MeThoS:
Originally posted by riot:
Originally posted by dahkota:
And, the color palette is unlimited in film where it is limited (though not noticibly for most applications) in digital. |
Not at all. A ccd or cmos is often sensitive to a higher range of wavelengths than silver halide crystals, reaching well into the ultraviolet and infrared if left unfiltered. In terms of colour separation, colour film has emulsions that split it into red, green and blue segments - thus each portion of the film (microscopically speaking) can be full-red, full-green, full-blue or any combination of the three.
In comparison (although ccd and cmos elements are generally larger than silver halide crystals in normal film), each pixel on a digital image is composed of three sensors (like the emulsion), with coloured filters - a red, a green and a blue. Except that each of the three sensors can have values between 0 and 255 (assuming only 8bit output), rather than just being off or on.
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I think hes referring to the bit depth. A digital camera ca only capture in 12 bit, where film is much higher. I've constantly said that my pentax 67 velvia slides scanned in @ 4000 dpi produce a better file than what I see from digital. I haven't compared it to the 1ds Mark II, but I did compare it to a 1Ds. Not to mention that nice film look that my prints have over digital. For the studio, I wouldn't use anything but digital.
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I was referring to the bit depth also. My point is, film doesn't magically "have a colour" - red, green and blue grains can be on, or off. That's one bit colour. You can scan that to whatever bit depth you like, but there's a relationship to the resolution in terms of the colour detail you will get - see the link i posted earlier about aliasing. If you are (theoretically) scanning at the full physical resolution of the film, and assuming a PERFECT lens, each of your pixels is going to be either black, red, green, blue, yellow, cyan, magenta or white - no gradations of hue or lightness. Any such gradations are introduced by unsharpness between the film and the scanner's sensor, or more often (at lower resolutions) the sensor seeing lots of grains together.
This is fine, and this is the principle of film after all, but it's a mistake to say it film has a bit depth without considering its resolution in the equation. At a lower resolution, you get more colour detail. At a higher resolution, your colour detail approaches 1 bit. This would take some very hardcore maths to quantify though, and i'm not even going to try. |
That's if you scanned it at the res you stated previously ( like 12000 dpi), but no slide should be scannned above 5000 dpi. I'm only comparing digital 35mm cameras to meduim format or large format slides. There is no question that my 1D mark II is as good or better than 35mm film.
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10/04/2005 02:48:54 PM · #61 |
Originally posted by petrakka:
i think this argument is silly. comparing prints and numbers blah blah theyll both yield completely professional results, most people wont be able to tell the difference, and the ones that can (photographers usually) aren't going to be the people interested in putting any images they see to commercial use except their own.
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If everybody in the history of photography said "ah nobody will be able to tell the difference anyway", there'd never have been any development in technology at all. It's the discussion of this kind of issue that goads along progress, and helps people to know what they're getting themselves into (when they choose film or digital, for instance). Besides, are you seriously suggesting the only motive for trying to get the best results you can is for commercial use?
Originally posted by petrakka:
I think it all boils down to preference.
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Yes, but most people's preference is grounded in something or other, usually a set of facts that are important to them. Here is a discussion that presents such facts, allowing people to form an informed preference.
Originally posted by petrakka:
Discounting Ken Rockwell is kinda rubbish......dude knows what he's doing. |
Of course, he knows exactly how to push his agenda by giving skewed reviews as ammo to obsessive film-is-better fanatics.
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10/04/2005 02:58:05 PM · #62 |
Originally posted by MeThoS:
That's if you scanned it at the res you stated previously ( like 12000 dpi), but no slide should be scannned above 5000 dpi. I'm only comparing digital 35mm cameras to meduim format or large format slides. There is no question that my 1D mark II is as good or better than 35mm film. |
Nope, if you scanned it at 12000dpi you'd get on average one grain per pixel, that would give you either black, red, green or blue. Not even combinations. Dividing that resolution by 3 will give you an average of three grains per pixel, and assuming we get all three and in each pixel there's one of each a red, a green and a blue, then if your scanner is optically perfect, you'd at most get 1bit colour - one of black, red, green, blue, cyan, magenta, yellow or white.
In order to get full, true 8bit colour, or a possible 255 gradations of each red, green and blue, (sticking with our same super-vague theoretical approach) you'd have to have at least 255 grains in each the red, green and blue layer of the film - that's 765 grains per pixel. Using my previous figure of 12700 grains per inch, you'd need to scan the film at at most 12700/765 = 16.6dpi. You read that right. To get this full true 8bit colour guaranteed, you'd have to halve this number again to account for irregularity of grain on the film to make certain there are actually 255 grains in each layer on every section you scan. This is why scanning prints is generally preferable, but that's another discussion :)
[edit for clarification]
Message edited by author 2005-10-04 14:59:50.
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10/04/2005 03:04:34 PM · #63 |
Originally posted by riot:
This is why scanning prints is generally preferable, but that's another discussion :)
[edit for clarification] |
You lost me here. EVERYBODY knows it's much better to scan the original slide or neg over scanning a print. your figure's also don't make sense. 16 dpi? Come on.
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10/04/2005 03:06:22 PM · #64 |
| 12000 dpi is one grain per pixel? Huh? |
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10/04/2005 03:09:11 PM · #65 |
| 16.6 dpi...isn't that a dot matrix printer? |
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10/04/2005 03:13:47 PM · #66 |
This discussion reminds me of a conclusion I came to when first looking around the web for information about photography -- that there are some professional photographers that might use a medium format as an everyday knock-around camara, but consider any serious photography must be done with a large format. Anything smaller is considered a toy for those that don't know any better. I imagine comparing the quality of different toys would be kind of silly to them. But, boys will be boys when comparing the size of their 'toys'.
David
-slinks back into the shadows with my little p&s that 35mm shooters view with the same 'toyee-ness'.
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10/04/2005 03:19:00 PM · #67 |
Originally posted by MeThoS:
Originally posted by riot:
This is why scanning prints is generally preferable, but that's another discussion :)
[edit for clarification] |
You lost me here. EVERYBODY knows it's much better to scan the original slide or neg over scanning a print. your figure's also don't make sense. 16 dpi? Come on. |
That's my point. Your suggestion you can get "true colour" is nonsensical on the grounds i stated above. To even get true 8bit colour, you'd need the number of grains per pixel only a 16.6dpi or lower scan could give you. Therefore scanning a (chemical) print would be better for colour reproduction (theoretically), but worse for clarity.
Just to clarify, i'm not saying you can't scan at high res with 8bit or 12bit or 16bit, you can, and you'll still get colours all the way throughout the range - but you cannot get every possible colour within the 8bit range (which is only 255 shades of red, green, blue) on the actual film if you sample such small parts. There simply aren't enough grains. In comparison, a digital camera can record every value between 0-255 in red, green and blue for each pixel, giving much more colour detail.
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10/04/2005 03:25:18 PM · #68 |
Originally posted by MeThoS:
Off the subject a little, but anybody notice in the Photoshop CS2 that they have incorporated a 32 bit color mode? |
For making HDR (High Dynamic Range) photos, by combining three or more images of different exposures of a particular scene. The training video that comes with CS2 has a pretty good explanation and demo.
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10/04/2005 03:32:26 PM · #69 |
Originally posted by riot:
Originally posted by MeThoS:
Originally posted by riot:
This is why scanning prints is generally preferable, but that's another discussion :)
[edit for clarification] |
You lost me here. EVERYBODY knows it's much better to scan the original slide or neg over scanning a print. your figure's also don't make sense. 16 dpi? Come on. |
That's my point. Your suggestion you can get "true colour" is nonsensical on the grounds i stated above. To even get true 8bit colour, you'd need the number of grains per pixel only a 16.6dpi or lower scan could give you. Therefore scanning a (chemical) print would be better for colour reproduction (theoretically), but worse for clarity.
Just to clarify, i'm not saying you can't scan at high res with 8bit or 12bit or 16bit, you can, and you'll still get colours all the way throughout the range - but you cannot get every possible colour within the 8bit range (which is only 255 shades of red, green, blue) on the actual film if you sample such small parts. There simply aren't enough grains. In comparison, a digital camera can record every value between 0-255 in red, green and blue for each pixel, giving much more colour detail. |
Then why do my medium format film scannned @4000dpi out do a 1Ds?
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10/04/2005 04:08:02 PM · #70 |
Originally posted by riot:
Originally posted by petrakka:
i think this argument is silly. comparing prints and numbers blah blah theyll both yield completely professional results, most people wont be able to tell the difference, and the ones that can (photographers usually) aren't going to be the people interested in putting any images they see to commercial use except their own.
If everybody in the history of photography said "ah nobody will be able to tell the difference anyway", there'd never have been any development in technology at all. It's the discussion of this kind of issue that goads along progress, and helps people to know what they're getting themselves into (when they choose film or digital, for instance). Besides, are you seriously suggesting the only motive for trying to get the best results you can is for commercial use? |
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Hey buddy, you're gettin your undies in a bunch over nothing. Of course people want great quality in their images, but personally, I would rather spend time attempting to make the images than wasting time what medium they are on. This statement does not slow progress, it urges people to go shoot instead of count pixels. I would bet that more people that advanced photographic technology spent more time working on that than on making good photographs.
Originally posted by petrakka:
I think it all boils down to preference.
Yes, but most people's preference is grounded in something or other, usually a set of facts that are important to them. Here is a discussion that presents such facts, allowing people to form an informed preference. |
Of course preference is grounded in something, it's not like random. This discussion does present facts, but the overall message, in my opinion, is that you can great results with either medium. Arguing which is 'better' is a waste of time..because there are instances of either topping the other medium . Now efficiency, cost, etc...those are things to consider much more than which one is 'better' I think.
It's not always about choosing the highest quality medium, or what you can blow up the biggest.
National Geographic photographers still shoot 35 mm slides for the most part. That should tell you something. Each medium suits a purpose.
Originally posted by petrakka:
Discounting Ken Rockwell is kinda rubbish......dude knows what he's doing. |
Of course, he knows exactly how to push his agenda by giving skewed reviews as ammo to obsessive film-is-better fanatics. [/quote]
Well you're putting words in my mouth there...but yeah he knows how to get a reaction out of people which is another skill altogether...but
man, I'd rather listen to Ken Rockwell, by making amazing photographs he's proven that he has a valid opinion. It's better than listening to some pixel peeper spout resolution and DPI etc at me. I'd rather make a great image than can be printed only 8x10 than make a lame photo that maintains quality at 40x50.
I'm sure I leave myself open to more criticism here, but bottom line to me is different mediums fit different people, and the actual image matters a lot more than how big you can blow it up.
Message edited by author 2005-10-04 16:12:30. |
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10/04/2005 04:16:16 PM · #71 |
This tread was an interesting read. I recently had the opportunity to review a book by one of our local ladscape photgraphers that was a collection of photos shot in 35mm film, high end digital and medium format. His contention in the intro was that digital is getting so close to film that you coould not tell the difference anymore.
Well, I went though the book and picked our EVERY medium format photo in it without looking at the index. Now telling the diffenece between the digital and film Canon cameras was much more difficult.
Moral of the story, at least for me, is that digital is getting there but has a ways to go before it can meet the clarity and depth of a great medium fomat landscape. I confirmed this again at an art show by walking around looking at the large prints. There was no doubt which came from medium format.
With that said digiatl is still young. It will surpass film for sure. Hell, it already has for most applications. But put up a larger than posrter size print of a great landscape and you will be able to tell the difference.
IMHO of course. |
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10/04/2005 04:27:05 PM · #72 |
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10/04/2005 04:45:14 PM · #73 |
This has been interesting, but confusing for a SOG(Sad Old Git) like me, however to answer the original question:
For me, digital is easy and cheap and I can see what I take on the PC in minutes.
Film is kewl, expensive and I don't see what I took until I get the prints back...then it's too late.
I shot loads of film with 120, 35mm - but I just like digital now, cos it suits my type(tightass)
Steve |
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10/04/2005 04:51:25 PM · #74 |
Film definitely takes more skill.
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10/04/2005 05:16:21 PM · #75 |
Originally posted by MeThoS:
Film definitely takes more skill. |
No disagreement here. No chimping and no histograms. Not that I have any experience with film, to that degree.
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