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User: jdg

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  1. bought a 12 inch powerbook on Forbes Predicts 5% Desktop Share for Apple in 2005 · · Score: 1

    I recently bought a 12 inch powerbook rather than an x86 laptop to run linux. I'm still running Linux/x86/Suse9.2 on my desktop and servers, OpenBSD on my firewall.

  2. Re:There's MUCH more going on than "Bush & Ker on Blackboxvoting.org Raises Vote-Audit FOIA Request · · Score: 4, Insightful

    This audit needs to be done. A significant fraction of the US population is losing confidence that elections are being run fairly. The next step in this thought process is to decide that change can only come from methods outside the democratic process. Then we have bigger problems. Everyone, regardless of their political beliefs should be behind this.

  3. Re:35mm on Beyond Megapixels - Part II · · Score: 1

    You mean like this:

    http://www.kodak.com/global/en/digital/ccd/produ ct s/interline/KAI-11000CM/specifications.jhtml?id=0. 1.8.4.21.4&lc=en

  4. Re:Article is Wrong on Lenses on Beyond Megapixels - Part II · · Score: 2, Informative

    Well, the article did not state it quite correctly, but the size of the sensor certainly drives the maximum diameter of the lens elements in almost all lenses of the design forms used for cameras. In real life, the diameter of the lens elements is determined by two things: 1) the speed of the lens (f-number), and 2) the coverage (field of view & sensor size).

    Think of a limiting case. If you had a lens element in contact with the sensor, that lens element would have to be larger for a larger sensor. Often lens elements are quite close to the sensor because it is helpful in correcting field curvature.

    If you are interested in this stuff, take a look at Modern Optical Engineering by Warren Smith.

  5. Re:Telecentric Lenses and Silicon on Beyond Megapixels - Part II · · Score: 5, Informative

    I design lenses for a living.

    This statement is sort of correct. The real need for telecentricity is the limited acceptance angle of the lenslet arrays that are put on many sensors, particularly small pixel size consumer grade sensors. This is what causes the drop off in corner illumination with non-telecentric lenses in consumer grade digital cameras. Telecentricity is a real requirement, particularly in sensors which pixel sizes smaller than say 4um.

    Large pixel, higher end CCDs generally don't need the lenslet arrays because the fill factor on the pixel aperture is much larger, so there is not much of a problem with non-telecentric designs. There are no lenslets present to limit the acceptance angle. I have never seen reflections off the sensor be an actual problem. People also talk about ray bundles from one obliquity passing through the wrong filter on the color filter array in a non-telecentric design, but I have never seen this happen either.

    Longer wavelength light is generally eliminated by an infrared reject filter, so light rarely bleeds from pixel to pixel.

  6. Re:Kodak's been failing for a long time on Kodak Lagging in Digital World · · Score: 1

    Full disclosure -- I am a Kodak engineer.

    The poster seems unaware of the actual history of photography.

    Kodak made 135 format film (35mm format) before and after the introduction of the Instamatic in , I believe the early 60s.. The point of the 126 Instamatic and 110 cameras was to make it easy for customers (think your mother) to load the film. This was a big problem on 35 mm cameras of this era 60s-70s for many, many people. In addition, the 35mm cameras of this era were very expensive for anyone without a serious interest in photography. The Instamatic and 110 cameras were designed and priced for the mass market. They were never intended for professional or serious amateur photographers, who make up a small fraction of the market.

    Cameras and film in all these formats were available from multiple manufacturers. Indeed, under a DoJ agreement, Kodak was required to help other manufacturers compete. This is pretty far from a proprietary standard. In this era, by any standard, the quality of Kodak's color film was far better than any competitors.

    During the 80s and 90s, the Japanese manufacturers perfected reliable auto loading point and shoot (non-SLR) 135 mm cameras with reasonably good zoom lenses. Now your mother could load the film, and lower cost 35 mm non-SLR cameras became the mass market standard. While the Japanese manufacturers were doing this, Kodak developed the Disc camera system, which flopped in the market place. In this same time frame, Fuji developed high quality color film. Fuji and others certainly gained market share for film during this era, but it's quite a stretch to say that they cleaned Kodak's clock, considering Kodak still is the worldwide leader in sales. The Kodak KB series of 35 mm cameras are huge sellers worldwide.

    The APS camera system (aka Advantix, SmartFilm, etc.) was developed by a consortium of companies including Kodak, Fuji, and several Japanese camera manufacturers. From a technical point of view, it offered a lot of nice features -- better storage of negatives, 3 formats, smaller form factor. The quality of many of the cameras was very high and the slightly smaller negative drove advances in camera optics and film technology. The APS system had some success in the marketplace, but did not displace 35mm non-SLRs.

    My Kodak digital cameras (DC240, DX4900) are open standard. Jpeg files, Compact Flash, FAT file systems, USB connections. If I plug either my DC240 or my DX4900 into my Suse 9.0 box, it just works. You can upload images to Ofoto (a Kodak company) for printing using any web browser. I'm not sure what part of this "philosophy", the poster thinks needs changed.

  7. Re:Difficult to use or? on First Preview of GIMP 2.0 Ready for Testing · · Score: 1

    I struggled with the gimp program, read some book, struggled some more, then I discovered a book called "Grokking the Gimp". It worked for me, it might work for you. I have no relationship with the author or publisher, etc.

  8. Re:Pentax K-1000 on Best 35mm SLR Camera for Beginners? · · Score: 1

    The Minolta XD-11 also has one great feature. Although it has an electronically timed shutter, they retained one completely mechanical shutter speed, so the camera will operate and take photographs with the battery completely dead, provided you can estimate or bracket the exposure.

  9. Numpy and other modules on FSF Awards Guido van Rossum For Python · · Score: 1

    The Numerical extensions to Python make it a fabulous language for engineers and researchers trying to get stuff done in a hurry. The language itself is easy to learn and use for real work.

    Similarly, their is tremendous power and ease of use in the other modules that come with the language.

  10. Re:Lack of Choices on What's Holding Up Broadband in the U.S.? · · Score: 1

    In Rochester, NY, you buy the DSL line from the phone company and then choose from one of the multiple ISPs available. The phone company (Frontier) bills you for the DSL line and the ISP bills you for their service.

  11. wrong, wrong, wrong on Build Your Own 10Mbit/sec Optical Data Link · · Score: 1

    power/area on the retina is what matters.

    Laser systems can be beamshaped to provide much
    higher power densities than incoherent thermal sources.

  12. Re:can anyone compile it? on Kernel 2.4.17 Out · · Score: 1

    I built it without problem. net/network.o build
    okay. I haven't installed it yet. I'd be happy to email you my .config file if you want.

    jdg at eznet dot net

  13. Re:Correction on More Links And Reports On Terrorist Attacks · · Score: 1

    Our local TV news (Rochester,NY) reports border
    crossings at Niagara Falls are closed.

  14. use pat2pdf to get pdf formatted patents on Delphion To Start Charging For Patent Access · · Score: 3

    You can use the pat2pdf script to get nicely
    formatted pdf formatted patents.

  15. Re:Gore really did on Experiences w/ Tech-Savvy Politicians? · · Score: 1

    Not true. Go read the New Yorker interview with
    Al Gore from about a year ago.

  16. Rochester, NY / Frontier residential DSL on A Study on Regional DSL and Cable Speeds? · · Score: 1

    1 Mbps down
    128 Kbps up

    I routinely get these rates.

  17. write to your elected representatives on More About Copy Control on Hard Drives · · Score: 1

    What we need here is a campaign where everyone writes to their elected representatives (congessman/woman, senator, M.P., whatever) and expresses concern about this. I would phrase it in terms of "Not only is this morally wrong, but I can no longer operate my business with this hardware."

  18. Re:Vision Station: 1024x768? blah on [In]expensive Immersion? · · Score: 1

    What matters is the angular resolution. That is, what angle is subtended by each pixel from the viewing location. The human eye only resolves about 1 minute of arc, except for the case of horizontal lines parallel to the horizon, where we can resolve about 4 seconds of arc.

    You'd have to work out how much angle is subtended by each pixel at the viewing distance of this thing.

  19. Re:Laptop on Red Hat Linux 7 Released · · Score: 1

    Not exactly a response, but I've run Red Hat 5.2 and 6.2 on a IBM Thinkpad 701 for a long time. This is a 486/75, 24MB ram, 650mb disk machine with sound and modem built in. Everything works well and out of the box, although I've always built custom kernels. Gnome/KDE are too heavy for this machine, so I've used icewm.

    Not sure how "ancient" your laptop is.

  20. Re:Achieving Parity With CCDs? Not quite... on Startup Claims 16.8M Pixel Camera Sensor · · Score: 1

    Motion images are much more forgiving than still images. A single frame of a motion picture projected as a still image won't look real great to you.

  21. Re:4096x4096 on Startup Claims 16.8M Pixel Camera Sensor · · Score: 1

    The chip is built with 0.18 micron technology.
    The pixel size is much larger - you can calculate the pixel pitch from 22mm/4096=.0054mm=5.4um.

    Note that 0.18 um is about 1/3 the wavelength of green light.

    Photographic grains have a size of around 1um

  22. Re:Technology is getting crazy... on The VLT Observes Comet LINEAR's "Shower" · · Score: 1

    I heard a talk (for a nonspecialist audience) this spring by a University of Rochester astronomer. He said that the improvements occuring now in the technology of astronomy are of the same importance as the Galileo's first use of the telescope. It's that big a change in what can be done.

  23. It's worthwhile reading "Database Nation" on Advertisers Agree To Privacy Restrictions - Kinda · · Score: 2

    Before you make up your mind about this issue,
    you might want to read Simson Garfinkel's new
    book "Database Nation". I found it informative
    and thought-provoking.

    I have no financial interest in the book, don't
    know Mr Garfinkel, etc.

  24. CNN reports Japanese monitoring system fails on Y2K Rollover - Post Your Experiences Here! · · Score: 1

    http://www.cnn.com/1999/TECH/computing/12/31/japan .nukes.idg/

  25. etoys screwed me on Online Gifts Not There Yet? You're Not Alone. · · Score: 1

    subject says it all