John Sheehy

Lives in NY, USA
Works as a Retired Communications Technician
Joined on Jul 9, 2003

John Sheehy's recent activity

  • Replied in Sensor Size
    Only if you want the added benefit of shallower DOF, and more light, for the same AOV. Otherwise, for the same AOV, the FF can use a lens with the same size aperture for the same DOF, and only the ...
  • Replied in Sensor Size
    The point that is often overlooked is that larger sensors only collect more subject light when they use a larger aperture and have shallower DOF, doing the same angle of view. That requires not ...
  • ... as you should be. Ask them to define "outperform", and what the conditions are. Sure, an add-on lens could potentially put more pixels on-subject than some cherry-picked DSLRs and their lenses, ...
  • I'm not sure any of the image comparison sites have any relevant material for the greatest potential difference between meta-Bayer shifts and single Bayer captures. That is why I suggested looking ...
  • ... but only by using a bigger lens, and/or accepting shallower DOF.
  • Replied in To what end?
    I don't like being hungry, either. That is why I eat foods and eat them in timing patterns in which I am almost never hungry. Eating all day, especially eating glycemic carbs all day, makes me hungry.
  • That sounds like something that makes sense on the surface of things, but it isn't borne out by endocrinology, and what experiments and trials have shown. The fact is, people who eat lightly all ...
  • ... and/or the low color resolution of most scenes. The spools of thread have no significant hue modulation in them; only luminance modulation. If the threads were made of a mixture of very ...
  • I'm not jealous of anyone who needs to park in the most chaotic and dangerous part of a parking lot. Even if it is raining, I park as far from the stores as possible with no apparent risk of the ...
  • Looks good compared to what ? Photos taken in isolation do not tell if the best choices were made.
  • Thanks for keeping the level of conversation low.
  • Replied in Sugar = sugar
    Agave syrup has more minerals that buffer some of the problems of sugar than sucrose, but fructose is fructose, and glucose is glucose. Most of what matters is how fast it digests and whether your ...
  • That depends on the context. At the right times, a small amount of sugar is completely harmless. If you wake up in the morning, go out for a 5 mile walk without breakfast, and then eat a spoonful ...
  • How strong is their message, though? I've seen ACS-sponsored war-on-cancer rallies where they were giving out name-brand candy bars. Is the AHA willing to pull their "Heart-Healthy" symbol from ...
  • I've watched or read a few experiments where randomized groups of people were given regular soda vs diet soda, and then let loose on a buffet where their food choices were measured, and the people ...
  • Not all cameras are as "ISO-invariant" as they are on paper. Just because your camera has 27% as much read noise (measured in RAW numbers or DN) at ISO 100 as at ISO 400, does not mean that it ...
  • True, but the eye shouldn't limit our equipment. Everything can be sampled at a higher resolution and magnified for our eyes. The limitations of human perception affect the final viewed product; ...
  • We need to stop simplifying things into untruths. The fact is, photographers have a varying range of needs, and people with modest needs need to stop living in a self-centered universe where ...
  • Stacked RGB gives the highest ratio of color resolution to luminance resolution. Foveon has weak color separation and high noise, though, and the aliasing, especially in the older models, can be ...
  • I went from 10D to 20D to 30D to 50D, and I found the image-level high-ISO noise to be similar for the 20D to 50D. 7D got a bit better, and 7D2 a lot better. Still room for improvement, though, ...
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