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bobn2

bobn2

Lives in United Kingdom Worcestershire, United Kingdom
Joined on Aug 28, 2007

bobn2's recent activity

  • @Androole re:"Of course, in these examples the smaller sensors will actually tend to be slightly better in terms of real-world signal-to-noise ratio. 1" is not a full stop behind M4/3, M4/3 is not...

  • When equivalence might be useful:
    1. When someone who has developed their technique on one format is thinking of moving to another, it gives a guide as to which settings to use to achieve the...

  • @boggis the cat re: "almost nobody wants to reproduce a shot as closely as possible using two systems, so "equivalent photos" is a pointless confusing factor."
    I don't think that's true. I don't...

  • @ Fygaren
    "Theta is the range of half-angles of whitch the light can enter the lens."

    Which is defined by?.....

    "I dont see the contradiction.Both depends on aperture is what Ive been...

  • @ Zdrasviti, re: "pixel size is the most important thing in terms of image quality thats why 12 mp full frame ( d3-d700) sensor is still the lowest noise level on planet."
    Wrong on both counts....

  • @MichaelJP, re: "that is the sensor performance at different ISO,
    that is how the sensor behaves with more amplification of the signal from each pixel".
    The signal to noise ratio of a competently...

  • @fygaren

    Interesting. I found the following that supports it:
    "f/number = 1 / [2sin(theta)]
    For very small values of theta sin(theta) can be approximated simply by theta which then allows us to...

  • @fygaren

    Re: "Interesting. I found the following that supports it:
    "f/number = 1 / [2sin(theta)]
    For very small values of theta sin(theta) can be approximated simply by theta which then allows us...

  • In atomic physics, it's conventional to define masses in atomic units, the mass of a proton or neutron. However, mass is energy, so unfortunately the binding energy of atoms changes their mass, so...

  • The magnification changes the spatial distribution of the noise, which might render it more visible. The SNR is determined by the number of photons captured, so strictly cropping reduces the noise,...

  • @rfsIii, re "There is nothing simple about optical science especially at the level we're discussing."
    Sorry, this is an application of very simple 'optical science' - from the introductory text....

  • @fygaren, re:"The hyperfocal formula you refer to is a simplified, easier to use in the field, version of Louis Derrs derived formula from 1906. His formula is considered to be the strictly correct...

  • @fygaren re: "I have already explained how one is the result of the other and not the other way around, you can not "set" the result and think what makes the result follows, this is...

  • @Fygaren
    Re: the f-number show the quantitative measure of lens speed so that you can set the right shutterspeed (before we had auto metering). An example of use is the sunny 16 rule."
    And so? You...

  • @ nigelht, re: "There are still differences. Just like there is a difference between using a TC and cropping but it's close enough to get the idea of what cropped sensors do."
    And if you put a 2x...

  • @Fygaren:
    Re: "The markings on the lens SHOW THE RESULTANT BRIGHTNESS" - well yes, but that 'brightness' really isn't of much significance. It isn't the same 'brightness' as you're going to view in...

  • @rfsiii - neither of those things. The photon noise SNR increases as the square root of the number of photons in the image and that increases linearly with the exposure time, other parameters kept...

  • @ Fygaren - of course, this whole discussion is a semantic game, so it depends on what you'd mean by lens speed. I would think that fundamentally lens speed depends on aperture diameter and angle...

  • @mostlyboringphotog - re "The reason exposure is/was the primary parameter in photography is that the correct exposure puts the image in the linear region of sensitivity of your sensor, film or...

  • @nigelht, re being at your ISO limit. Not by coincidence, ISO limits tend to be related in the same way as equivalence (that is, ff cameras have available ISOs higher than smaller formats) In any...

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bobn2 has not added any gear yet.
Total messages 5
Threads started 0
Last post 9 months ago
Total comments 44
Total likes 53
Last post 1 week ago
Total reviews 0
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Photos uploaded 211
Last upload Nov 28, 2010
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