Leonard Migliore

Leonard Migliore

Lives in United States Sunnyvale USA, CA, United States
Works as a Retired
Has a website at http://www.laserk.com
Joined on Jan 4, 2004

Leonard Migliore's recent activity

  • Replied in Wow
    Humans are primates.
  • For distant objects, doesn't a 100mm lens produce an image twice the size of one generated by a 50mm lens? Isn't that why we use telephotos?
  • Replied in Wow
    Most of our problems are due to crazed primates.
  • I had no issue with the 12MP of my D300. I only got a 24 MP D750 for its substantially better high ISO performance. But I could do reasonably big prints from the D300 as long as I didn't crop much. ...
  • The exposure will be the same. That's what f/numbers are for. The entrance pupil of the 100mm lens is twice the diameter of the entrance pupil of the 50mm lens. This means it has four times the ...
  • Sometimes it's hard to tell. That's wrong because it doesn't take into account the distance between the principal planes.
  • I believe that walking a test chart out to infinity is not practical. Also, what would that tell you about focal length?
  • What do the parenthetical numbers signify?
  • But mirrorless cameras should be cheaper; they have fewer moving parts and internal optics. I realize they're trying to recoup development costs but the manufacturing cost of a Z7 should be much ...
  • That was what I attempted to point out. Unless you understand the mathematics, it's nothing but received wisdom; it doesn't clarify anything.
  • The problem is that you're attempting to understand optical concepts without going to the effort of understanding the principles behind them. Focal length is actually something quite abstruse. I ...
  • Replied in Human nature
    Well, I feel cheated if I don't get everything I can out of the image. So with a high-rez camera, I'm going to try to get the picture sharper by, say, using a shorter exposure time. It lets me ...
  • You will need a neutral density (ND) filter to allow long exposure times with proper exposure. If you want, say, a 1 second exposure in daylight at f/8 and ISO 100 you need an 8-stop filter. Such ...
  • Replied in Definitions
    Well, if you put an extension tube or a close-up lens on a camera lens, you have to move closer to be in focus. That's the whole point of those devices. Note that if you move closer to an object ...
  • Replied in f/1.0 lenses
    How are you supposed to use that 90mm Elcan on a rangefinder camera? You can't see out the RF window because the lens blocks it. And you'd really want to get the focus right on that thing.
  • By "aperture" one may mean the relative aperture (like f/2.8), the entrance pupil diameter or the physical size of the opening in the diaphragm. I was trying to remove the possible ambiguity in ...
  • Replied in Less confusion
    As I read the instruction sheet, it seems to me that the adapter cuts off any light above f/4. But it doesn't change the aperture from what you set. For example, if your exposure was 1/250 at f/8 ...
  • Replied in Less confusion
    Yes. Front-mounted converters do not change the f/stop. Now, they usually degrade the image, distort and vignette but you still have the same f/stop.
  • Replied in An attempt...
    Maybe it can be defined like that but it would not be correct. As a counterexample, I have a 20mm focal length lens for my Nikon DSLR. You can't have any glass closer than 38mm from the sensor or ...
  • Replied in Less confusion
    you probably mean a 20mm f/2.8 Yes. Front-mounted converters do not change the f/stop.
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Total messages 17467
Threads started 30
Last post 2 hours ago
Total comments 4
Total likes 40
Last post Mar 22, 2019
Total reviews 0
Entries 1
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Last entry May 6, 2015
Photos uploaded 127
Last upload Feb 3, 2017