I like Hubble a lot, but other missions which don't require (or allow) Shuttle service and cost on the order of $0.3-0.8 billion seem to me far more cost effective. The mirror is a tiny fraction of the cumulative operations costs.
It shorted, and burned enough plastic or wiring to trip the overpressure sensor (do wire shorts smell in space?). See this message from the Space Telescope Science Institute. Side A electronics are available which might be able to run a portion of the instrument. This has been expected since the first failure last summer, and "contingency" proposals are available to keep the observatory running using its other instruments (ACS has recently been the most used).
Trees are not permanent carbon sinks. On timescales of several decades, they release the carbon they have stored right back into the atmosphere, as they decompose, or are burned in clear cutting or natural fires. At best they buy us 20-50 year to figure out how to deal with the problem, and at worst they accelerate global warming by reducing the albedo at crucial latitudes. There are many other good reasons to plant trees, but as a panacea to global warming, nothing can match simply not releasing the excess carbon in the first place.
Except the human eye can resolve no more than about 1 arcmin. So, assuming you sit close enough to your 25' screen so that it fills your field of view, you'd need only 27 mega pixels to fully saturate the human visual system. A more careful calculation reveals the true limit is around 15 mega-pixels:
This is about 230x fewer pixels than you assume in the first step of your calculation. The only reason to demand more pixels is so you can walk right up to your screen, stand 2 feet away, and appreciate the rich detail in the 1% of the scene you can see. This may be useful for still pictures (which is why even 20 mega-pixels is always not overkill for digital imaging), but it is complete overkill for video.
I highly doubt this. In my experience, it's much easier to pick up a decent digital signal, even with a small indoor amplified set of rabbit ears/UHF dish, than the equivalent analog signal. That's the beauty of a digital signal: it takes amplification very well. From my point of view, mandating digital will only improve the quality of over the air reception of the average user.
All TVs 36" and larger were mandated to have built-in HD tuners (known as ATSC tuners) beginning March 2005. By March, 2006, the maximum size without tuner will drop to 26", and by March, 2007, all new televisions will be required to carry the tuners. If you bought a TV recently, it likely has an ATSC tuner. If you aren't using it, you should be.
I recently set up my father in law with a cheap amplified set of rabbit ears for his new Panasonic 42" EDTV Plasma TV. He's in Las Cruces, NM, and we were easily able to pick up 5-7 digital channels from El Paso, TX, over 60 miles away! Most prime time networking is transmitted in 720p or 1080i, and even the non prime-time programming, which is simply up-converted to HD, looks clean and static free -- a remarkable improvement over traditional analog broadcasting, and analog cable quality. The broadcast HDTV is of remarkable quality (even on a widescreen EDTV display). PBS in particular has some outstanding HD programming, and typically most prime time, major sporting events (think: Olympics), and other high-rating programming is now being produced originally in HD.
He liked it so much, he's cancelling his cable, and just enjoying the pristine, over the air programming brought to you free of charge by the largesse of our fine friends at the FCC. My mother in law calls the little radioshack antenna "the satellite dish". Somehow I just can't manage to convince her that what she is watching is being beamed free over the air.
If you have a new TV, but are too cheap to get HD cable or a satellite service, check the digital transmission status of your local broadcasters, drop $40 at your local radio shack, and let the fun begin.
Today's announcement that Apple will be phasing itself to the Intel architecture comes as no surprise to this writer since it's simply a smart move. I also first got wind of this deal back in 2003 and expected it to have been announced this January. I missed it by one keynote and 5 months. It's not a secret that I have been suggesting that Apple do this through most of the 1990's and most recently in 2001 (see links below). So when I got wind of it actually happening and wrote it up in this column it seemed, at least to many Mac heads, that I was making it up in desperation. I'd invite the readers to go back to those columns and read what the Mac blowhards had to say about it.
The best explanation I heard of this somewhere was by analogy to authors and books. The codec (MP3, AAC, OGG,...) is like the language a book is written in, and the encoders are like authors. Authors well versed in an old, out of date language can still produce exceptional books. A new language sometimes comes along which has greater power of expression, more nuance, etc. This doesn't mean good books are written with it by default. Authors may not be familiar enough with it yet to take advantage of all its improvements. Eventually, the best authors master the new language, and produce new books which surpass even the best written in the old language, but this depends on the supply and attention span of authors.
Re:Extra Special Olympics
on
Juiced
·
· Score: 4, Funny
Dennis Miller: In response to what its sponsors claim is an idea whose time has come, the first All-Drug Olympics opened today in Bogota, Columbia. Athletes are allowed to take any substance whatsoever before, after, and even during the competition. So far, 115 world records have been shattered! We go now to correspondent Kevin Nealon, live in Bogota for the Weightlifting Finals. Kevin?
Kevin Nealon: Dennis, getting ready to lift now is Sergei Akmudov of the Soviet Union. His trainer has told me that he's taken antibolic steroids, Novacaine, Nyquil, Darvon, and some sort of fish paralyzer. Also, I believe he's had a few cocktails within the last hour or so. All of this is, of course, perfectly legal at the All-Drug Olympics, in fact it's encouraged. Akmudov is getting set now, he's going for a cleaning jerk of over 1500 pounds, which would triple the existing world record. That's an awful lot of weight, Dennis, and here he goes.
[ Kevin steps aside to reveal the steroid-bulked athlete bent over to lift the 1500 lbs. weight. Sergei tightens his grip on the barbells and pulls up, but instead of lifting the weights, his arms are pulled off and blood squirts ferociously out of his pulpy stubs.
Kevin Nealon: Oh! He pulled his arms off! He's pulled his arms off, that's gotta be disappointing to the big Russian! [ Sergei's trainer wraps a towel around him ] You know, you hate to see something like this happen, Dennis! He probably doesn't have that much pain right now, but I think tomorrow he's really gonna feel that, Dennis! Back to you!
Dennis Miller: Thank you, Kevin. Very nice form on the Russian. Canada, of course, is leading that competition.
A perfect example of how a very lightweight programmable interface would be really useful: a common problem in digital (and film) photography is limited dynamic range. A scripting interface to a digital camera could help overcome this.
First the problem. Just to give you some walking around numbers, typical desktop displays offer about 7-8 stops of contrast (e.g. 100:1), high-end plasma TV's offer 10 stops (1200:1), typical natural scenes have a dynamic range of about 18 stops, and the human eye, at a single pupil dilation, can appreciate about 17 stops (well matched to natural, sun-illuminated scenes, not by accident!). When you allow for the adjustment of human vision to illumination conditions, the human brain-eye system can appreciate about 30 stops of dynamic range (a factor of 1 billion:1!), from the faintest star to full-on sunlight. Needless to say, it is impossible to come anywhere close to this with consumer imaging technology.
An interesting way to expand dynamic range and alleviate the problem is to take several exposures with an increasing sequence of exposure times. Typically, to maintain focus and field depth, you'd keep the aperture fixed, keep the CCD gain fixed, and only vary exposure time. With a simple programmable interface to a digital camera, you'd be able to roll your own HDR mode, "scripting" the camera to e.g., take a quick succession of 5 frames separated in exposure time by 1 stop, and store them all in an aptly named sub-directory on your flash card. Trivial to implement, if provided the hooks. Combining the 5 exposures with suitable post-processing can then simulate much large contrast than normally available. An example of this technique is here. As it is, we just have to hope the camera manufacturers provide something like this for us (at whatever price point they find compelling).
Re:Welcome to capitalism
on
HIV Vaccine
·
· Score: 2, Insightful
That would be a good argument, except the widely touted costs of research and development that pharmaceutical companies offer to justify their high prices are actually factors of two or more smaller than their gargantuan marketing budgets! When's the last time you've heard a mega-pharm complain:
We'd like to offer our product cheaper, but we have to recoup the tremendous costs of those sexy celebrity voice-overs exulting the horrible digestive and sexual dysfunction side-effects our drugs cause.
I find it interesting that the film-scanner crowd can claim increasingly large gigapixel images just by upping their scan resolution. At some point, your scan has resolved the film grain, and you are gaining no new information, just justifying your RAID array. They could scan their same filmstock at.5 microns and claim 100 GigaPixel images. It's not just the number of pixels, but what information they contain.
Impressive work, but if you are going to claim multi-gigapixel status, you need to back it up by clearly stating the inherent resolution limits in the film (which, in their case, are very high, but not unlimited).
I saw Michael Moore in Tucson, AZ this past Monday. At one point he said:
I think you know my film `Farenheit 911' came out on DVD today. And, you know, I don't really agree with the Copyright law as it stands today. I just want as many people to watch it as possible. So, when you get it, I think you know what to do.... burn baby burn.
He also mentioned that bootleg copies of F911 were widely circulating among troops in Iraq, and that he had "no idea how they got there".
... the chief distinction being that if they had just lowered the prices, the return refund would equal the amount paid, instead of more than the amount paid (after rebate). Yet another reason to get rid of rebates.
That's one of the true advantages of DSLRs like the Nikon D70: much better memory buffering (treating flash like a hard disk). You can take 17 6MP pix at 3fps and an indefinite number at ~2fps.
Actually, you're wrong. Imagine a set of mile markers set off in the distance you are imaging. Now imagine you've setup the same lens on a 35mm and DSLR, side by side, to capture the exact same field of view (same number of mile markers). To get the same field of view, you'll need to zoom the 35mm camera in. To get the same f-number, you'll need to open up its pupil aperture to 1.5x as big (it's collecting more light, as someone below points out, because it needs to preserve not total luminous input, but surface brightness per square mm of film). So we have our two cameras taking the exact same picture at the exact same exposure value, but one is zoomed in and has a larger aperture.
In order to reach the film/sensor, a bundle of rays must pass through the pupil aperture, aka the "iris". Consider the bundle for the mile marker post #123 on the extreme right-hand side of the scene. For the 35mm camera, the aperture is bigger (e.g. 1.5x as big), hence the bundle of rays accepted from that milepost is bigger, hence the actual amount of glass it traverses is bigger. If the aperture and hence bundle of rays is too big, and the field angle at the edge of the sensor is too large, part of that bundle will be shadowed by the lens hood and you'll have vignetting: again not so much of a problem for DSLRs (but a real problem for wide-angle lenses)! This is a real physical effect.
Yes, the front surface of the lens accepts light from mile post #123 over its entire diameter, but most of those photons are rejected by the aperture stop (i.e. they fall on the iris pupil and never makes it through). For a given FOV, the aperture diameter is *smaller* for DSLRs, simply because the focal length needs to be reduced.
The bottom line is standard 35mm lenses are overdesigned for DSLR usage, accomodating a larger pupil aperture than needed for a given field of view. Less of the lens really is used, and luckily, all problems of chromatic and spherical aberration increase drastically with field angle: in this case sticking to the "center of the lens" should be thought of the angular sense, and really does improve the image quality. The flip side of this is that DSLRs will be more forgiving when it comes to lens quality, since they don't stress the off-axis performance as much.
If you don't believe me, take a very wide angle lens on you 35mm film camera, open up the aperture as wide as possible, and take a highly-contrasting scene. Notice how the center of the image is sharper and more color-accurate? Get out your scissors and cut out the central 1/2 of that picture. You've just replicated what a DSLR at the same lens settings would have produced. Nicer looking, eh?
By the way, the terminology "equivalent focal length" when applied to DSLR lenses is a complete misnomer: see this comment.
Re:Focal length multiplier, DOF, and ISO/CCD issue
on
Beyond Megapixels
·
· Score: 3, Informative
The "focal length" multiplier is a complete misnomer. In reality, a given 35mm lens which is expecting a 35mm piece of film (24mmx36mm) is actually confronted with a smaller detector (e.g. 16mmx24mm), yielding a smaller field of view. Claiming a given lens is magically enhanced by a factor of 1.5 similar to the APS "panorama" format which consists soleley of chopping off the top and bottom of the frame, a feat you could accomplish just as well with a sharp pair of scissors.
The only way in which a 300mm lens is remotely like a 450mm lens when used with the smaller physical sensor is that they would deliver the same field of view. The problem is, a given lens produces a image whose sharpness is a fixed physical size (like.01mm) in the focal plane. The smallest point feature is blurred to this size at the film or sensor.
As a reductio ad absurdum which illustrates the issue, imagine a standard 35mm telephoto lens with 300mm maximum focal length, used with an ultra-tiny CCD sensor exactly.02mm across. The field of view present in the image is in fact equivalent to having a 360,000mm=3km lens -- I can see the bright red metallic print hawking this on the lens packaging now. Think of the stunning shots you can take of shy and endangered wildlife in the next state over from the comfort of your own porch! Sadly, thanks to the limits of the lens optics, such an image would contain only 4 independent blobs of color (completely independent of the number of pixels in which those blobs are captured).
In reality, since the cost drivers for lens design is performance "off axis" or away from the optical center, coupling a high-performance 35mm lens with a smaller sensor is wasting this off-axis performance: the maximum field angle is going to be smaller! This may however allow you to use cheaper 35mm lenses which would suffer from unacceptable aberrations at large field angles with digital cameras, since you're only using the "center of the glass".
The Nikon D70h can take more than 17 frames at 3fps and 44 frames in 20s. It is remarkably faster than the 300D. Take a look here, which also includes a sound clip of the high-speed action.
Re:As an ex-commercial photographer
on
Beyond Megapixels
·
· Score: 2, Interesting
1. Store data in RAW format. (Thanks to Sigma for pushing this.) This get rid of the useless "low/medium/high quality" switch on the camera. There goes one pointless switch.
2. Store all data at the highest resolution. Get rid of the "small/medium/large" switch. If I needed to store more pictures on my card, I would have bought a higher-capacity CF drive. I can get 4GB models now. That should be enough to store hundreds of pics. Another pointless switch, gone...
One reason storing RAW data at the highest resolution is not always the best idea: the bandwidth to flash needed to keep up with a stream of images being taken is greatly increased! This is because modern cameras have fast buffer memory, and slow (think hard drive) flash memory. The more images can be shuffled through the buffer before requiring a write to flash, the faster a sequence of images you can take! The consumer digital SLRs are up to ~3fps for 10's or even 100's of frames!
For those of you interested in digital panoramic photography, there's an excellent open source package making great strides, not just emulating but completely surpassing commercial offerings in its category. In the latest test releases, it can even fully automate the process of identifying and calculating the overlap of matching pictures, and compensating for color and intensity mismatches between adjoining frames.
It's called hugin, and is available here. It even outputs layered files which capitalize on capabilities recently added to the Gimp 2.0!
Take a look! You might also like to see the worlds first gigapixel image created using the techniques hugin employs here.
Do you really believe a WAV or FLAC file contains music in it's "original format"? Of course it doesn't. It's a compromise, designed to be "good enough", which limits the temporal sampling rate, the frequency bandwidth, and the digital encoding depth of sound intensities. The original recorded format, as created in the sound studio, likely has a much higher sampling rate and bandwidth, just as the film or digital master of production movies has much higher bitrate than DVD video.
The particular compromise for CD's produces very good results on good equipment, but there's no fundamental (physical or technical) reason that these precise limits were chosen: they were based on typical human acoustical response and the limitations of sound reproduction equipment, driven by the cost-to-market and feasibility of a given data volume/second! CD's could have been designed to hold only 22min of music sampled at 32bit and 88kHz, but that wouldn't meet marketing or customer expectation, and wouldn't actually benefit the majority of equipment (ears included).
The compressed file formats trade size by making more significant and less obvious compromises, but are nonetheless in the same class: a limited, digitized realization of a continuous source. Increasing download bandwidth and further research will likely yield future formats which rival CD quality for all practical (and conceivable) purposes. Of course, by then we'll have 24bit, 192kHZ DVD-audio (in, ironically for the present discussion, the AAC format), and you'll still complain that the newest generation of super-high-fidelity compressed music isn't "original". If you want your music "original", go hear it in person.
Comcast has recently begun a similar campaign of "bundling" cable service with cable television subscription here in Arizona (and nationwide, I believe), most likely as an attempt to plug the gaping torrent of cable customers leaving for satellite. What's amusing is that it's actually more expensive to get cable alone than it is to get cable+the cheapest TV service (which works out to about $55). When the Comcast representative explained their new bundling deal by comparing it to a Happy Meal at McDonald's, I asked him whether McDonald's ever offers just the hamburger for more than the cost of the entire Happy Meal. He failed to see the crushing nuance of this argument.
What you're failing to envision is the following rather likely scenario:
1. Thanks to the support of hundreds of developers, free
software application ABC is developing rapidly, and
quickly becoming the best application in its niche.
2. Company XYZ takes ABC, and in short order integrates it
into a proprietary product they call ABC++. They add
technical support, a fancy new interface, and improve
the speed. XYZ aggressively markets ABC++, giving it
away in the back of magazines. It can write the same
kinds of files and accept the same type of network
connections that ABC does, which serves to speed up its
adoption.
3. ABC++ gains in popularity. Every time the hard-working
ABC developers fix a bug or add a feature, XYZ quickly
integrates it into ABC++ and releases a new version.
ABC++ is rapidly becoming a nicer piece of software
than ABC, since XYZ relies on the work of its own paid
programmers in addition to the hundreds of ABC
developers.
4. Motivated by its controlling board to increase profits,
XYZ decides to increase the price of the now wildly
popular ABC++ program to $100. To avoid a backlash of
users "downgrading" to the still-free ABC program, they
change the internal file formats and network connection
protocols ABC++ uses to be incompatible with ABC.
Users must make a choice: pay for the nicer ABC++ with
its large base of installed users, or go back to ABC,
with its dwindling user base.
5. ABC developers, aware that their user base is about to
be stolen, reverse engineer the file formats and
network protocols used by the new ABC++ and release a
compatible version. XYZ threatens suit appealing to
the DCMA, since the new protocols made use of some
trivial encryption. ABC loses developers, and more and
more users adopt XYZ's product.
6. Five years later ABC is dead. It cannot interoperate
with any modern applications, and has very few users.
XYZ has effectively plucked ABC from the world of free
software and used it to make their fortune.
7. Five years later, the over-confident and now complacent
XYZ management makes critical errors, allowing company
QRS to surpass it with a new competing program. XYZ
declares bankruptcy, and ABC++ is no-longer supported.
No source is available; both ABC++, and ABC, are dead.
Slashdot Mirror
Total HST cost: $6 billion
Yearly HST operations budget: $337 million
Single servicing mission in 2008: $900 million
I like Hubble a lot, but other missions which don't require (or allow) Shuttle service and cost on the order of $0.3-0.8 billion seem to me far more cost effective. The mirror is a tiny fraction of the cumulative operations costs.
It shorted, and burned enough plastic or wiring to trip the overpressure sensor (do wire shorts smell in space?). See this message from the Space Telescope Science Institute. Side A electronics are available which might be able to run a portion of the instrument. This has been expected since the first failure last summer, and "contingency" proposals are available to keep the observatory running using its other instruments (ACS has recently been the most used).
Trees are not permanent carbon sinks. On timescales of several decades, they release the carbon they have stored right back into the atmosphere, as they decompose, or are burned in clear cutting or natural fires. At best they buy us 20-50 year to figure out how to deal with the problem, and at worst they accelerate global warming by reducing the albedo at crucial latitudes. There are many other good reasons to plant trees, but as a panacea to global warming, nothing can match simply not releasing the excess carbon in the first place.
Except the human eye can resolve no more than about 1 arcmin. So, assuming you sit close enough to your 25' screen so that it fills your field of view, you'd need only 27 mega pixels to fully saturate the human visual system. A more careful calculation reveals the true limit is around 15 mega-pixels:
http://www.swift.ac.uk/vision.pdf
This is about 230x fewer pixels than you assume in the first step of your calculation. The only reason to demand more pixels is so you can walk right up to your screen, stand 2 feet away, and appreciate the rich detail in the 1% of the scene you can see. This may be useful for still pictures (which is why even 20 mega-pixels is always not overkill for digital imaging), but it is complete overkill for video.
Also note that more than 80% of homes already get their programming from cable or satellite, and I can't see this move as anything but good, probably resulting in more over the air users than anytime in the last 15 years.
I recently set up my father in law with a cheap amplified set of rabbit ears for his new Panasonic 42" EDTV Plasma TV. He's in Las Cruces, NM, and we were easily able to pick up 5-7 digital channels from El Paso, TX, over 60 miles away! Most prime time networking is transmitted in 720p or 1080i, and even the non prime-time programming, which is simply up-converted to HD, looks clean and static free -- a remarkable improvement over traditional analog broadcasting, and analog cable quality. The broadcast HDTV is of remarkable quality (even on a widescreen EDTV display). PBS in particular has some outstanding HD programming, and typically most prime time, major sporting events (think: Olympics), and other high-rating programming is now being produced originally in HD.
He liked it so much, he's cancelling his cable, and just enjoying the pristine, over the air programming brought to you free of charge by the largesse of our fine friends at the FCC. My mother in law calls the little radioshack antenna "the satellite dish". Somehow I just can't manage to convince her that what she is watching is being beamed free over the air.
If you have a new TV, but are too cheap to get HD cable or a satellite service, check the digital transmission status of your local broadcasters, drop $40 at your local radio shack, and let the fun begin.
The best explanation I heard of this somewhere was by analogy to authors and books. The codec (MP3, AAC, OGG, ...) is like the language a book is written in, and the encoders are like authors. Authors well versed in an old, out of date language can still produce exceptional books. A new language sometimes comes along which has greater power of expression, more nuance, etc. This doesn't mean good books are written with it by default. Authors may not be familiar enough with it yet to take advantage of all its improvements. Eventually, the best authors master the new language, and produce new books which surpass even the best written in the old language, but this depends on the supply and attention span of authors.
First the problem. Just to give you some walking around numbers, typical desktop displays offer about 7-8 stops of contrast (e.g. 100:1), high-end plasma TV's offer 10 stops (1200:1), typical natural scenes have a dynamic range of about 18 stops, and the human eye, at a single pupil dilation, can appreciate about 17 stops (well matched to natural, sun-illuminated scenes, not by accident!). When you allow for the adjustment of human vision to illumination conditions, the human brain-eye system can appreciate about 30 stops of dynamic range (a factor of 1 billion:1!), from the faintest star to full-on sunlight. Needless to say, it is impossible to come anywhere close to this with consumer imaging technology.
An interesting way to expand dynamic range and alleviate the problem is to take several exposures with an increasing sequence of exposure times. Typically, to maintain focus and field depth, you'd keep the aperture fixed, keep the CCD gain fixed, and only vary exposure time. With a simple programmable interface to a digital camera, you'd be able to roll your own HDR mode, "scripting" the camera to e.g., take a quick succession of 5 frames separated in exposure time by 1 stop, and store them all in an aptly named sub-directory on your flash card. Trivial to implement, if provided the hooks. Combining the 5 exposures with suitable post-processing can then simulate much large contrast than normally available. An example of this technique is here. As it is, we just have to hope the camera manufacturers provide something like this for us (at whatever price point they find compelling).
You mean like this?
That's why they changed it to:
http://arxiv.org
I find it interesting that the film-scanner crowd can claim increasingly large gigapixel images just by upping their scan resolution. At some point, your scan has resolved the film grain, and you are gaining no new information, just justifying your RAID array. They could scan their same filmstock at .5 microns and claim 100 GigaPixel images. It's not just the number of pixels, but what information they contain.
Impressive work, but if you are going to claim multi-gigapixel status, you need to back it up by clearly stating the inherent resolution limits in the film (which, in their case, are very high, but not unlimited).
He also mentioned that bootleg copies of F911 were widely circulating among troops in Iraq, and that he had "no idea how they got there".
Good stuff.
That's one of the true advantages of DSLRs like the Nikon D70: much better memory buffering (treating flash like a hard disk). You can take 17 6MP pix at 3fps and an indefinite number at ~2fps.
In order to reach the film/sensor, a bundle of rays must pass through the pupil aperture, aka the "iris". Consider the bundle for the mile marker post #123 on the extreme right-hand side of the scene. For the 35mm camera, the aperture is bigger (e.g. 1.5x as big), hence the bundle of rays accepted from that milepost is bigger, hence the actual amount of glass it traverses is bigger. If the aperture and hence bundle of rays is too big, and the field angle at the edge of the sensor is too large, part of that bundle will be shadowed by the lens hood and you'll have vignetting: again not so much of a problem for DSLRs (but a real problem for wide-angle lenses)! This is a real physical effect.
Yes, the front surface of the lens accepts light from mile post #123 over its entire diameter, but most of those photons are rejected by the aperture stop (i.e. they fall on the iris pupil and never makes it through). For a given FOV, the aperture diameter is *smaller* for DSLRs, simply because the focal length needs to be reduced.
The bottom line is standard 35mm lenses are overdesigned for DSLR usage, accomodating a larger pupil aperture than needed for a given field of view. Less of the lens really is used, and luckily, all problems of chromatic and spherical aberration increase drastically with field angle: in this case sticking to the "center of the lens" should be thought of the angular sense, and really does improve the image quality. The flip side of this is that DSLRs will be more forgiving when it comes to lens quality, since they don't stress the off-axis performance as much.
If you don't believe me, take a very wide angle lens on you 35mm film camera, open up the aperture as wide as possible, and take a highly-contrasting scene. Notice how the center of the image is sharper and more color-accurate? Get out your scissors and cut out the central 1/2 of that picture. You've just replicated what a DSLR at the same lens settings would have produced. Nicer looking, eh?
By the way, the terminology "equivalent focal length" when applied to DSLR lenses is a complete misnomer: see this comment.
The only way in which a 300mm lens is remotely like a 450mm lens when used with the smaller physical sensor is that they would deliver the same field of view. The problem is, a given lens produces a image whose sharpness is a fixed physical size (like .01mm) in the focal plane. The smallest point feature is blurred to this size at the film or sensor.
As a reductio ad absurdum which illustrates the issue, imagine a standard 35mm telephoto lens with 300mm maximum focal length, used with an ultra-tiny CCD sensor exactly .02mm across. The field of view present in the image is in fact equivalent to having a 360,000mm=3km lens -- I can see the bright red metallic print hawking this on the lens packaging now. Think of the stunning shots you can take of shy and endangered wildlife in the next state over from the comfort of your own porch! Sadly, thanks to the limits of the lens optics, such an image would contain only 4 independent blobs of color (completely independent of the number of pixels in which those blobs are captured).
In reality, since the cost drivers for lens design is performance "off axis" or away from the optical center, coupling a high-performance 35mm lens with a smaller sensor is wasting this off-axis performance: the maximum field angle is going to be smaller! This may however allow you to use cheaper 35mm lenses which would suffer from unacceptable aberrations at large field angles with digital cameras, since you're only using the "center of the glass".
The Nikon D70h can take more than 17 frames at 3fps and 44 frames in 20s. It is remarkably faster than the 300D. Take a look here, which also includes a sound clip of the high-speed action.
One reason storing RAW data at the highest resolution is not always the best idea: the bandwidth to flash needed to keep up with a stream of images being taken is greatly increased! This is because modern cameras have fast buffer memory, and slow (think hard drive) flash memory. The more images can be shuffled through the buffer before requiring a write to flash, the faster a sequence of images you can take! The consumer digital SLRs are up to ~3fps for 10's or even 100's of frames!
It's called hugin, and is available here. It even outputs layered files which capitalize on capabilities recently added to the Gimp 2.0!
Take a look! You might also like to see the worlds first gigapixel image created using the techniques hugin employs here.
The compressed file formats trade size by making more significant and less obvious compromises, but are nonetheless in the same class: a limited, digitized realization of a continuous source. Increasing download bandwidth and further research will likely yield future formats which rival CD quality for all practical (and conceivable) purposes. Of course, by then we'll have 24bit, 192kHZ DVD-audio (in, ironically for the present discussion, the AAC format), and you'll still complain that the newest generation of super-high-fidelity compressed music isn't "original". If you want your music "original", go hear it in person.
Comcast has recently begun a similar campaign of "bundling" cable service with cable television subscription here in Arizona (and nationwide, I believe), most likely as an attempt to plug the gaping torrent of cable customers leaving for satellite. What's amusing is that it's actually more expensive to get cable alone than it is to get cable+the cheapest TV service (which works out to about $55). When the Comcast representative explained their new bundling deal by comparing it to a Happy Meal at McDonald's, I asked him whether McDonald's ever offers just the hamburger for more than the cost of the entire Happy Meal. He failed to see the crushing nuance of this argument.
What you're failing to envision is the following rather
likely scenario:
1. Thanks to the support of hundreds of developers, free
software application ABC is developing rapidly, and
quickly becoming the best application in its niche.
2. Company XYZ takes ABC, and in short order integrates it
into a proprietary product they call ABC++. They add
technical support, a fancy new interface, and improve
the speed. XYZ aggressively markets ABC++, giving it
away in the back of magazines. It can write the same
kinds of files and accept the same type of network
connections that ABC does, which serves to speed up its
adoption.
3. ABC++ gains in popularity. Every time the hard-working
ABC developers fix a bug or add a feature, XYZ quickly
integrates it into ABC++ and releases a new version.
ABC++ is rapidly becoming a nicer piece of software
than ABC, since XYZ relies on the work of its own paid
programmers in addition to the hundreds of ABC
developers.
4. Motivated by its controlling board to increase profits,
XYZ decides to increase the price of the now wildly
popular ABC++ program to $100. To avoid a backlash of
users "downgrading" to the still-free ABC program, they
change the internal file formats and network connection
protocols ABC++ uses to be incompatible with ABC.
Users must make a choice: pay for the nicer ABC++ with
its large base of installed users, or go back to ABC,
with its dwindling user base.
5. ABC developers, aware that their user base is about to
be stolen, reverse engineer the file formats and
network protocols used by the new ABC++ and release a
compatible version. XYZ threatens suit appealing to
the DCMA, since the new protocols made use of some
trivial encryption. ABC loses developers, and more and
more users adopt XYZ's product.
6. Five years later ABC is dead. It cannot interoperate
with any modern applications, and has very few users.
XYZ has effectively plucked ABC from the world of free
software and used it to make their fortune.
7. Five years later, the over-confident and now complacent
XYZ management makes critical errors, allowing company
QRS to surpass it with a new competing program. XYZ
declares bankruptcy, and ABC++ is no-longer supported.
No source is available; both ABC++, and ABC, are dead.