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hmathias

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About hmathias

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  1. When the leading digital cinema motion picture camera manufacturer ARRI had to make this decision with their industry-leading ALEXA camera, they chose High Dynamic Range sensors (14 camera stops) over resolution and kept the native chip sensitivity at EI 800. When they wanted to increase resolution, they also made the sensor chip larger and added the ALEXA LF camera to their lineup. I trust that Leica will make the same prudent judgements. They never chose big numbers over image quality. Harry
  2. Higher noise, unfortunately, is a byproduct of higher sensor resolution. Given the same imager dimensions, the smaller the size (higher density) of photosites in a high-res sensor means that less photons impact each site. This reduces the quantum efficiency of the light-to-image signal transfer. Higher resolution sensors — baring new technological breakthroughs — have more noise, are less light sensitive and usually exhibit harsher gray scale reproduction. Sorry, but that is physics. Harry
  3. Yes image format and maximum image blowup is considered as two of the main considerations when choosing CofC.
  4. Actually, it is well-known that DoF is a mathematical formula with the main variables being f/stop, lens focal length, and object distance to the point of lens focus. But there are 2 other variables that must be taken into account, diagonal of the final image (image format). That is why a medium format lens (or an 8x10 view camera lens) must have a smaller DoF than a full-frame 35mm image. The other variable is maximum permissible "CofC". This is a variable that tells the DoF formula what the maximum permissible size of the out of focus “circle” that will be tolerated before the image i
  5. No, in the long run, subtle artistry is the best part. But, I conceded that many of my students would agree with you. (subtle needle with no hostile intent).
  6. That’s actually pretty straight forward: a 40mm anamorphic lens has the DoF of a 40mm lens but the horizontal coverage of a 20mm lens, plus the height of a 40mm lens. Plus it produces oval “circles of confusion” and you can’t throw focus without making the audience motion sick. See my my still photography and some motion picture reels at: HarryMathiasImages.com
  7. In addition to the factors mentioned, lens DoF depends on the “circle of confusion” factor used to compute the DoF tables (or lens barrel engravings). “CofC” gives the diameter of the maximum allowable out of focus “circle” that will be tolerated before the image is considered out of focus. Theories of what this should be could vary between lens design generations. For example, in motion picture applications we use smaller CofC than still photography because motion picture images are blown up much more to be shown on theatre screens.
  8. My 21mm SEM f/ 3.4 is a superb lens with no issues at all, ever. It has been my experience using dozens of extremely wide angle lenses in my Cinema work, (and many of these lenses are even more expensive and exotic in design then even the Leica 21 mm SEM F3.4 lens). Typically in cinema we don’t care what these lenses cost as long as their performance is superb, because we rent these lenses for the duration of the film project, and we don’t buy them. Most of the finest extremely wide-angle lens designs do not have a very large maximum aperture, compared to the higher focal length l
  9. Remember, Ansel Adams was using an 8"x10" view camera. It was easier to move the van then the camera. Harry
  10. The 21 SEM f/3.4 is a fantastic wide lens that I frequently use in situations where I wouldn’t use any other wide lenses, because it has no distortion to speak of. And it’s reasonably priced, for a Leica lens. there is a thread here of Ulta-wide M lens pictures and all of the best are taken with the 21 mm SEM.
  11. Not sure where it fits on the old vs new rendering spectrum… But the 21 SEM f/3.4 is a fantastic wide lens and would help you on the wide end if you got rid of the 24mm. And it’s reasonably priced, for a Leica lens.
  12. As most of you know: One of the three factors of the amount of Depth of Field is the distance to the point of focus. The other two being aperture, and lens focal length. Many of the examples in this excellent thread of pictures where the DoF seems excessively small is simply the result of the principle point of focus being too close to the camera. This is easily fixed (if it’s a problem) by stopping down slightly. This isn’t a problem that can be blamed on the Noctilux as a lens of choice.
  13. OK. So someone is renting the lens that they "teardown" to see if it is built correctly? Or do they just throw it away afterwards?
  14. In my experience (extensive in evaluating and testing lenses) There is rarely a reason to "tear down a lens" unless it has been dropped, and then tearing down lenses won't help because lens companies won't sell you (or their dealers) individual barrel parts and lens elements. And you couldn't cement the elements and center them properly if they did. The major lens companies are masters at evaluating their own lenses and have extensive testing tools to do this, (not the ones suggested). That is how Leica and Zeiss decide which designs to bring to market. And do glass melt re-optimizations, as g
  15. I looked over Lensrental's testing procedure. I found it to be very rigorous, very nerdy, and nothing like the optical industry's standards for lens evaluation. I am sure that it works for their own needs, but I am not sure that you can extrapolate any general conclusions from their results. Whether NASA does or not. I would also question "their years of experience" compared to Leica, Zeiss, or Panavision. Harry
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