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herbko

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Everything posted by herbko

  1. Very nice! I like the second one best also. The first sawblade shrimps shot look good also. Too bad there's another critter in the background that's a bit of a distraction.
  2. 1. Image quality, mostly dynamic range 2. Fast Auto focus and no shutter lag 3. High ISO range
  3. I think I share you view about this branding gibberish. The point I'm trying to make is that the image processor's tasks are dependent on the sensor design. Canon is up to Digic III. All the Canon CMOS cameras have one of the three chips. If Nikon did the same thing they may be up over 10 by now, which may make the branding of those chips less effective. The fact they are choosing this time to brand their image processor suggest to me that they've converged on a design, and do not plan to do one CMOS camera followed by a CCD followed a LBCAST.... I also read that the sensors on these cameras are their own design and not from Sony. The two suggest to me that they've finally got their design and process act together and plans to use that in the future. If it really is true that the two new sensors are not from Sony. I'll stick my neck out and predict that with the possible exception of the D40x upgrade, Nikon is done with Sony.
  4. Renaming it to "visually lossless" is their new face saving spin. Have a look back at the D70 introduction. It was just lossless at that point. I guess the spin is working. http://www.dpreview.com/reviews/nikond70/page2.asp
  5. Sure. Canon marketing played up their DSP. The point is this is not possible if you're using a different one for each camera you build because each has a different sensor design. The fact that Nikon is now doing this suggests that they will continue with one line of DSP design which I think really only works if they stop switching sensors with every camera.
  6. Nikon had called their previous lossy compression scheme "lossless". They'll have to come up with a good face saving way to explain the new format to the masses.
  7. I think this is more than sales and marketing at work. The new sensors are Nikon designed processed by their own contract fab. I think they will now converge on this and evolve both the sensor and the DSP and use it all the new designs as Canon has done all along. Previous to this they been using CMOS and CCD from Sony as well as their own LBCAST which probably required different DSP's. Going forward I think they'll dump Sony and go with their own for all new designs. It makes sense. I wouldn't depend on a competitor for such a key component in a market with so few players.
  8. Since the housings probably won't be ready until that time, there's no rush. If it's roughly the same camera with more pixels and more noise and lower dynamic range which would you choose? Looks like Canon will have to adjust their prices on the 1DsIII in light of this new competition.
  9. First, they are 12-bit converters, and the state-of-the-art in that is probably good enough to be not much of a factor. Also, multiple A/D's have threshold matching problems which can show up as noise or patterns. Since, Sony is sending this out they're likely to have a good handle on it, but it's not clear that is not a noise contributer.
  10. The 6 db/bit is the range. The difference is that to get to the maximum signal-to-noise, SNR, that most specs quote, you have to divide by the quantization noise which is a fraction of a bit, so that number is about 2db higher. It could be limited by the sensor or the A/D. If a careful test gives 12.5 bits we still won't know which it is.
  11. The maximum dynamic range of a 12-bit A/D is 20*log(2^12) = 72db. State of the art for high speed ones seems to be around 70db. http://www.analog.com/IST/SelectionTable/?...on_table_id=197 The 14 bit converters are probably ~1.5 bit better than the 12-bit ones. The 5D cell area is about 30% bigger. The new generation sensor design from Canon may not have improve things that much.
  12. That seems to be close to the state-of-the-art: http://www.analog.com/IST/SelectionTable/?...on_table_id=203 The 12-bit A/D don't have 12 effect bits either, so the 14-bit ones are about 1.5 bits better. Has anybody checked amazon.com
  13. Perhaps I didn't word that very well. I'm not saying that the 14-bit converter will give 2 stops better ISO performance, and I agree that the extra bits are at the "bottom" of the range. Let me try again with an example.... Set the 14-bit camera at ISO 100 and the 12-bit camera at ISO 400. If the exposure is correct for ISO 400, both cameras will give the same signal-to-noise raw outputs with the same number of useful quantization levels with the top two bit of the 14-bit camera always 00. However, the shot of the 14-bit camera will not be over exposed if the "correct" exposure happened to be ISO 100. So in effect you can shoot ISO 100-400 exposure at ISO 100 setting and get at least a good 12-bit output. If the exposure level is ISO 400, the 14-bit camera will not give a better output than the other one. If you happen to over expose what you thought was an ISO 400 exposure, you're protected by a couple of stops. I think the high dynamic range mode in the 1DIII is doing something like this. What's more interesting is that you can think of exposing the bright parts of you image at ISO 100 ( the sunball for example ) and dark parts at ISO 400, and bring the ISO 400 parts up to ISO 100 in post processing. The signal-to-noise of the dark parts will be no better than an ISO 400 exposure, but it would not be limited by quantization problems. As I mentioned before even if the sensor has less than 12 stops of range as defined by the RMS noise level, there is still information below this level. It's better to record it than to cut it off, especially in cases where you have to bring up the darker levels for dynamic range reasons.
  14. The area of the 1.6x sensor is about 2/3 the area of the 1.3x sensor, so the signal-to-noise of the 40D should be within one stop of the 1DIII at the same exposure and ISO. Even if by the usual definition of dynamic range, max signal/noise level, the sensor is not quite 12 bits, there is still information below the RMS noise level and the extra resolution will still help. It'll make the parts below noise level fuzzy instead of banded. Looking at it another way, with a 14-bit A/D the parts of a shot that are 2 stops under exposed will have the same sensor output as the same sensor with a 12-bit A/D set to 2 stops higher ISO. Assume the same sensor, the output of an ISO 100 shot with the 14-bit A/D will be no worst than an ISO 400 shot with 12-bit A/D. If nothing else, it will give you room for underexposure in cases where you want to really be sure to preserve the highlights. I'm not surprised that Canon put the 14-bit A/D in the 40D. It probably cost them less to make just one Digic III and associate IO that process 14-bit and use it for all the camera than to make 2 versions. The only incremental cost is a little more memory for the same shot buffer.
  15. Here's some old data on the flash duration of a few underwater strobes. http://wetpixel.com/i.php/full/inon-d-2000...al-explanation/ The Inon D-2000 has a significant advantage over the others. This came out before the Z-240. My guess is that the brighter Z-240 will be a little slower to deliver full power.
  16. I agree. If you decide to go with Photoshop, you'll want the version with the raw converter. If you already own Photoshop 5 you can get a Photoshop 7 upgrade + a Photoshop CS3 upgrade. The two will probably cost less than the full CS3.
  17. There must be an inside joke somewhere. Beautiful shots Jenny. You've even managed to make a tail shot look good. Very creative. I love Cannibal Rock and Yellow Wall also.
  18. I traded my Ys90's for Z220's a few years ago. In my tests, the Z220's have a wider beam and is about one stop brighter.
  19. I think you may be confusing the 8-bit color graphic scheme with the 8 bits per channel format of common photo encoding like JPEG. For display and print, 8 bits per channel is enough. I'm not aware of any display or print devices that are much better than that. 16 bits per channel is better when you are adjusting the image. After the final adjustments are done, you shouldn't see a difference in converting to 8-bits.
  20. The low noise sensor and 14-bit A/D converter is a combination that's unmatched for the capture of images with large dynamic range, like sunball shots. The 1.3x crop format does not have a lens that's optimal for sunball shots. I'd wait until Canon puts the new sensor and A/D into the 5D and 1Ds2 replacements.
  21. Nicely done Jenny! I really like the Bumpheads also.
  22. I wouldn't worry about that. I think there's more ways to do a web site than sewing a shirt together, and fashion designers are still in business.
  23. I see from the EXIF of the photo that you shot that with an 85mm lens. The shark is too far away; there's too much water between the lens and the subject. You'll have to get closer with a wider lens. For your Canon 300D the typical lenses for that kind of shots are 15mm fisheye or 10-22 zoom.
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