Slashdot Mirror
Improving Digital Photography
Milican writes "'It's easy to have a complicated idea," Carver Mead used to tell his students at Caltech. "It's very, very hard to have a simple idea...And now one of Mead's simplest ideas--a digital camera should see color the way the human eye does--is poised to change everything about photography. Its first embodiment is a sensor - called the X3 - that produces images as good as or better than what can be achieved with film.'" We had a previous story about Foveon last February.
How is this at all like the way the human eye sees?
I hate pixel noise in my digital pictures. I have heard that since red color has to be detected at the deepest part of the silicon there is an abudance of noise in the reds.
0xfeedface
in Photography. Check out the article here.
Random is the New Order.
For those of you interested in a review of a X3 camera and a simple explanation of the technology behind it, this review is pretty decent.
for an excellent (as usual) review of a camera based on this sensor check dpreview
http://www.dpreview.com/reviews/sigmasd9/
-- the cake is a lie
It sees a real "color" instead of on red/green/blue (dispersed in fine pixels of course). It may not be able to see red quite as well as other colors, but it only means that the sensitivity at the red level is the limitation you have for the picture as whole.
What you don't get is Moire patterns - at all!! That is what you probably hate when you say you hate "pixel noise" because it's totally obvious (due to the color changes), very distracting, and annoying to clean up after.
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Film still rules for taking pictures in low-light. Digital cameras just can't handle low-light situations, by their very nature.
Plus, the speed of film is better. Digital cameras aren't very good for action photography.
So, uh, yeah. Digital is great for posed shots in good lighting. So I guess it is the best. Whatever.
Remember, I said "please be sure you have used the gear".
The ISO 1600 and 3200 shots from the pro digitals are easily less grainy and have better dynamic range than their film counterparts. Try it. And my EOS-1D can do 1/16,000 shutter speed with zero lag. Is that fast enough for you?
Yet another person who is bashing without trying.
STOP . AMERICA . NOW
How many people own a $4-5k (or more) camera? The models you list are wonderful for professional photographers and studios, but don't slam the average user for not being able to afford pro gear. Current consumer devices take relatively good photos. Still not as good as a hobbyist with a midlevel analog camera can do.
Most importantly, not many consumer level output devices can print photos as well as film. I have seen some really nice photo prints from digital but, on the average, still not as good as well developed film.
Actually, for really low light situations(astronomy) digital cameras are preferred by many because they are much more light sensitive and have no reciprocity failure (the pixels do not "tire" of getting light like film does). We (amateur for me) call them CCD cameras but the technology is the same.
Do you mean long exposures, or low contrast? For long exposures, this four minute exposure disagrees with you. In the article the guy says he couldn't even see that terrace it was so dark.
:D
What do you think it is about low light situations that precludes digital cameras from working well?
As for speed.. yeah, my digital camera only goes up to ISO 1000. But you don't have to go to 1000 to take normal non-posed shots successfully (There's a lot of space between posed shots and extremely fast moving action shots.)
You forgot to add that you can't use UV or IR film in digital cameras.
Trees can't go dancing
So do them a big favor
Pretend dancing stinks!
No new screens would be needed. This new sensor only affects the way an image is captured, not how it is displayed. Current CCD chips actually use 4 "pixels" to record each pixel of the image. 1 red sensing pixel, 1 blue sensing pixel, and 2 green sensing pixels. It is set up like the following for each pixel the camera records...
:)
RG
GB
The CCD device in a digital camera has one of these set up for every pixel the camera is to capture.
This new way will allow all 3 colors to be captured on one "pixel" instead of 4, so that will allow much higher resolution pictures to be taken. Hopefully this simplified explanation makes sense, and didn't totally confuse everyone
Besides, night scopes are digital, and they seem to work ok. You can even buy them at CostCo.
t's pixelated still so you will still get Moire patterns as soon as the smallest details are finer than the resolving power of the X3 bins (think Nyquists theorem). However, the bizarre colours you get from a fine-grained black and white grid shouldn't be present to the same extent as all the measurements of colour intensity are done at the same point in the X3 layer, as opposed to the different spatial positions of the red green and blue bins in a colour CCD.
The bizzare colors (what I really hate about digital photos) are not just reduced - they are gone. If you read the review at DPReview.com you'll find that it has resolution right up to Nyquist is noise free and you get some detail beyond. Here's the relevant section (near the very end of the review, where they test against some resolution charts):
The SD9 is capable of delivering all nine individual lines of the horizontal or vertical resolution bars up to its maximum absolute resolution (sensor vertical pixel count) and slightly beyond. Note also that because the X3 sensor doesn't need a color filter array it doesn't suffer from color moiré.. Absolute resolution is just less than the Canon EOS-D60, Nikon D100 and Fujifilm S2 Pro (at 6 mp).
However, because the X3 sensor doesn't use a low pass (anti-alias) filter it is able to resolve detail all the way up to Nyquist. Beyond Nyquist the system will alias without any objectionable color moiré. Where a Bayer sensor camera would turn detail beyond Nyquist (such as distant grass texture) into a single plane of blurred color the SD9 will continue to reproduce some individual pixel detail (without color moiré).
"There is more worth loving than we have strength to love." - Brian Jay Stanley
Film still rules for taking pictures in low-light.
So that's why the shuttle keeps visiting the Hubble Space Telescope, to pick up the film!
The is also a company called SBIG that makes a line of digital imagers for amatuer astronomers.
Steve M
As much as Foveon's well hyped and widely advertised (*cough*thanksslashdot*cough*) idea seems to make sense on the surface, their solution is far from perfect.
To sense an RGB (Red, Green, Blue) pixel one can use a veriety of methods. At the center of this technology lies the ability to turn a stream of photons into an electric current. This photodetector is colorblind, it is only capable of measuring the _amount_ of light, not it's color. To recognize color the estheblished method used to be to put several photodetectors near each other and put color filters in front of them. The most widely used color filter array is known as the Bayer pattern and consists of 2 green photodetectors (diagonal from each other) a blue and a red detector in a 2x2 grid. These 2x2 blocks are then repeated over and over to create the full image sensor.
Specialized software or hardware needs to take these individual Red, Green or Blue pixels and recreate a single RGB pixel, this technique is known as demosaicing. The major advantage of this method is the simplicity of the photodiode (photodetector). It allows for the creation of very dense image sensors that are now passing the 10MegaPixel barrier while keeping the cost down (start seeing 5MegaPix sensors for less then $100 before the end of this year).
Foveon's approach is to layer these color filters vertically.
The good:
- idealy you get R,G,B at each pixel.
The bad:
- very complex layered photodiode technology, this makes the pixels significantly bigger. Currently the pixels are bigger then a 2x2 bayer image pixel. The complexity also adds to the manifacturing cost, these chips will not be cheap for the forseable future.
- Color bleeding. For example: Photons in the green wavelenght do not nescecarily stop in the green layer, but might be picked up by the underlying red layer. This means that specialized hardware needs to apply a non-trivial color correction for each pixel layer.
Foveon's idea is a very interesting approach. Since they nicely pattented their idea shut, we will have to patiently wait for this single company to provide the world with this technology.
Side fact: The human eye see's colors using pigments that respond differently to different wavelengths. In the simplest model we can say that we see Red Green and Blue with spatially seperated pigments that resemble a bayer image sensor closer then the foveon's sensor.
Too much hype. All they did was stack pixel detectors rather than mosaic them. The mosaic was simpler and now cheaper, this thing costs $1800 in a camera, else I'm sure someone could've come up with it. The real accomplishment is creating those silicon layers precisely, not coming up with lets stack em
They say the resolution is like a 120mm film, and the color lattitude is big. So are CMOS sensors in Canon and Nikon's cameras. Checkout the awesome photos on photo.net. A lot of those have been shot by modern digital cameras with CCDs and they dont look bad. Mead has his own marketing to do to try and take Foveon to Intel and Microsofts level, so he has to push down CCD. Theres a reason why people are buying digital cameras with sensors smaller than fingernails and submitting their pictures on professional photography site. I think Mead has work to do.
"Give orange me give eat orange me eat orange give me eat orange give me you." -Nim Chimpsky
Ha!
Yes, and don't forget the other end of the spectrum too, that these cameras can take wonderful long exposures as well. The D60 in particular can sit on Bulb for minute after minute without any major noise or pixel errors. Taking ten minute bulb exposures seems fairly "low-light situation" to me. I've had comparable results with the D100 has well. I also regularly take 10 to 15 second exposures with it, and never once have I had to contend with excess noise, boomy shadows, or any other difficulties.
Me thinks these people are playing with their friend's Kodak DC3400 or something.
V
The resolution (as determined by number of pixels) will not get better. Manufacturers are currently counting each one-color pixel in the
RG
GB
blocks as one. That block is 4 pixels. Foveon-based cameras would have
(RGB) (RGB)
(RGB) (RGB)
which is still 4 pixels, but gives you more accurate color information at each pixel and reduces moire. So, while there will not be any more pixels per area with Foveon CCDs, the *effective* picture resolution will be much better.
I wish I had known this before I shopped for digicams-- it feels like false advertising to me, and I learned after I had made my purchase. Manufacturers ought to be required to state "4 single-color Megapixels" or "1 Megapixel effective with color" for 4MP cameras with traditional CCDs.
This is amazing technology, and it will revolutionize digital cameras if/when it comes down in price. HOWEVER, this is not how the human optic system works. Even in our optics, we have seperate receptors for red, green, and blue, and our brains do the interpolating. As most will remember from basic elementary biology, our eyes detect light through rods and cones. All quotes are from this link. "The retina has ~126 million photo receptors, 120 million rods and 6 million cones." Rods gather any light they can, and compile the data together to show the best possible image in the dimmest light; therefore, rods will display a black and white image. This is why the darker it gets, the harder it is to differentiate yellow from white: you are depending more and more on the rods.
HERE is where it gets interesting, and where I get to my point. Cones are what we use to see color. An individual cone cannot see red green and blue as this marketing hype would lead us to believe. "The cones come in three types: Red (60%), Green (30%) and Blue (10%). The red and green cones are randomly distributed in the center of the fovea and the blue cones form an annulus around the outside." So in effect this camera will actually surpass the human eye.
As a side note, the link goes to a very interesting document that states how "126 million photoreceptors must be transmitted to the brain via 1 million fibers in the optic nerve [while] [t]he overall compression ratio of 126:1 is not evenly distributed." Check it out.
Primarily because it is still a bit buggy and bleeding edge. CCD is a proven technology, with a lot of time put in to its development. That is why Nikon has stuck with CCD chips. Canon has been using Bayer CMOS chips in some of their prosumer cameras, but the top of the line 1Ds still uses a CCD chip.
X3 still displays some odd behaviors under certain conditions, and until these problems are resolved, the "big guys" aren't going to want to put it into a high end camera -- especially when their customers have grown to expect a certain level of all-around quality and attention to detail from them.
V
It all depends on your definition of "nice film-based SLR." I was $3-4k into Canon film cameras before I bought my D60; I don't think that's uncommon--one lens now, a new flash later, then a new body, it all adds up over the years.
So, adding a $2,200 D60 wasn't a *huge* step, price-wise. I've had it around 6 months, and I've shot around 7,000 frames with it. Assuming for the moment that I'd have shot the same number of frames had I been using film, that averages out to $0.35/frame, which is in the same general range as film and processing (that's $10 for 36 exposures).
Assuming that I've got at least another couple years of functional use in the camera, the per-frame cost should drop down under a dime. Plus, I get instant feedback (nice when fiddling with lighting problems) and it's easier for me to sort, edit, and produce prints with digital then it is with film.
So, with six months of use, you can start to argue that it's paid for itself. Add another couple years of use, and it'll be hard to argue that it would have been cheaper to use film. So, even if it has no resale value in 3 years, it'll still have been a good move, financially speaking.
I suppose it all depends on how much you shoot.
Film does have pixels, in one word, grain. The advantage of film is the grain is randomly distributed, not rigidly organized into rows and columns. That helps blend edge transitions, reducing the prominence of jaggies and Moire effects.
The pro cameras have significantly better dynamic range than the consumer cameras. There is, however, a great deal of variation among pro cameras as well with the Fuji S1/S2 apparently turning in the best results (I shoot with Canon glass, so I haven't used the Fuji cams). This site's pro -level camera reviews often quantify each camera's dynamic range compared to others.
In my opinion, the real key is the storage format. Consumer cameras generally store in 24-bit (8 per channel) compressed (i.e. JPEG) format and you lose a great deal of information that way -- the limitation is the storage format itself (JPEG), which isn't capable of holding all of the color and light information the camera captures -- the camera simply throws it away before storing the image. Of course in some low-end consumer cameras, the sensor is that poor to begin with.
With pro cameras you generally store the important shots in a raw format (12-bit per channel, 36-bit total) that discards nothing; you can then manipulate this in Photoshop as a 48-bit uncompressed image in a wide colorspace and get dynamic range and color reproduction very similar to what you can get with good quality film. If you happen to be on the road with your pro digital and need your images to stay as small as possible, many higher-end cameras will also allow you to shoot in JPEG format but using an enhanced colorspace (i.e. Adobe RGB rather than sRGB) to try to preserve this additional information while still gaining the benefits of compression. However, to use such JPEG images you must have software which supports these enhanced colorspaces (i.e. Photoshop does, GIMP does not).
STOP . AMERICA . NOW
But that's not all you're paying for. You're not counting the cost of storage and printing. DIY-enlargements work out to a couple bucks per 8x10 (about the same as having film enlarged to the same size). And what about ink longevity?
You have a lot of good points. I've spent about a hundred on film storage since I took up photography (negative/slide sheets, storage boxes, etc), and I've bought an extra 80 GB hard drive to store pictures from the digital camera. I have a 35mm film scanner, and I was using it to scan and print negatives before I got the D60, so a lot of the printing comparisons break down. Anyway, 90% of the time, I get prints by burning a CD and dropping it off at the local Costco with a Frontier, so the print cost and longevity are the same as film prints. I have a decent inkjet, and I use it occasionally, but you can't really compare it to conventional prints--I can print any size up to 13x19, and I can spend hours tweaking it to look the way I want it to look. 95% of the time, there's something wrong with machine prints, either from digital or film, but it's ususally too much of a pain to get it fixed. A DIY printing solution gives you a lot more control, at the cost of taking longer. So, I use both--if I'm not feeling super-critical, I let Costco handle it. Otherwise I do it myself.
Also by storage I don't just mean the cost of a single hard drive, regardless of size. You've got backups, transfers to other media, etc., to worry about. And 20 years from now my negatives will still be in the box on the bookshelf, available for prints and enlargements. Where will your photoshop files be?
Good points, and mostly looking for a good solution. Except I've had a hard time finding several pages of negatives for the last year, and I have a bunch of other negatives that I cheaped out and had Costco reprint (rather then scanning them and giving them the files), and now they're scratched. Film and Digital *both* have storage issues. They're just not the same issues :-).