• Foundation 1482 posts
    April 27, 2023, 1:41 p.m.

    This thread started off quite reasonably, like this:

    and after nearly 400 interventions (mostly by the usual suspects)...

    I despair

    David

  • Members 369 posts
    April 27, 2023, 4:57 p.m.

    I often include a comment that photography is all about the light. Without light (or some form of electromagnetic radiation) there is no photography.

    That observation leads naturally to acknowledging that ISO isn't an exposure setting due to the fact it has no direct effect on exposure.

  • Members 3952 posts
    April 28, 2023, 1:45 a.m.

    That may all be true if the goal is a nice looking sooc jpeg. The lighting is also important for the final image when shooting raw, but ISO is not very important.

    But if shooting raw, and if as in my case the aim is to minimise visible noise then ISO has zero influence on how I set the optimal exposure** when hand-holding the camera. When I am ETTRing using a tripod then I lock in base ISO.

    How/why I set exposure* the way I do is explained in my "Why are my photos noisy?" thread.

    * exposure - amount of light that struck the sensor per unit area while the shutter was open
    ** optimal exposure - the maximum exposure* within dof and motion blur requirements without clipping important highlights.
    *** under exposed - more exposure* could have been added with the DOF and blur constraints still being met without clipping important highlights.

  • Members 2306 posts
    April 28, 2023, 6:19 a.m.

    iso 4000 raw processed no adjustments. iso 100 pushed to reach the same brightness as the iso 4000 image. the difference is in the shadows. WB is also off shooting underexposed.

    test shot noise.jpg

    test shot noise.jpg

    JPG, 1.6 MB, uploaded by DonaldB on April 28, 2023.

  • Members 3952 posts
    April 28, 2023, 6:29 a.m.

    Those images are meaningless because I cannot verify what processing might have been applied to the jpegs.

    Post links to the raw files.

    The exposures* are clearly different for each image because the scene luminances are different.

    * exposure - amount of light that struck the sensor per unit area while the shutter was open
    ** optimal exposure - the maximum exposure* within dof and motion blur requirements without clipping important highlights.
    *** under exposed - more exposure* could have been added with the DOF and blur constraints still being met without clipping important highlights.

  • Members 2306 posts
    April 28, 2023, 6:36 a.m.

    they are 1 at iso 4000 and the other at iso 100 😁 look at the exif info. thats the shift in WB look at the histogram.

  • Members 3952 posts
    April 28, 2023, 6:40 a.m.

    ISO has nothing to do with it, assuming the values displayed in your jpeg image are not falsified which is very easy to do.

    The aperture and shutter speed are the same in both, again assuming you didn't falsify the exif data displayed in the jpeg image, so the difference in exposure* is due to a difference in scene luminance as I described earlier.

    Those jpegs could have had strong noise reduction and who knows what other processing applied to them.

    You are withholding the raw files so clearly you are hiding something 🙂

    * exposure - amount of light that struck the sensor per unit area while the shutter was open
    ** optimal exposure - the maximum exposure* within dof and motion blur requirements without clipping important highlights.
    *** under exposed - more exposure* could have been added with the DOF and blur constraints still being met without clipping important highlights.

  • Members 2306 posts
    April 28, 2023, 6:53 a.m.

    You are withholding the raw files so clearly you are hiding something 🙂

    Do your own tests then as you dont seem to trust anyone so im not wasting my time discussing this any further.

  • Members 3952 posts
    April 28, 2023, 6:56 a.m.

    That's another example of you making statements that are not true.

    It is you I don't trust because you have not told the truth on too many occasions in these forums for me to just blindly accept any images you post as being authentic and legitimate.

    You are withholding the raw files, which is obviously your choice to make, but who knows what noise reduction or other editing might have been applied to those jpeg images.

  • Members 2306 posts
    April 28, 2023, 7:22 a.m.

    i will PM them to everyone else, but not you. easily fixed ,you dont want to be part of a sensible conversation then i will leave you out.

  • Members 3952 posts
    April 28, 2023, 7:28 a.m.

    No problem, and I assume you are certain no-one will then email them to me as well 😊

  • April 28, 2023, 8:12 a.m.

    Don, my own experience is that very often your posted 'tests' should be take with a very large pinch of salt. I'm sure that a lot of other users here that have wasted time taking them seriously could attest to the same. we even have examples in the lifetime of DPReview. I for one would not trust them an inch until you published every bit of surrounding information which would allow where the trick is without wasting time.

  • April 28, 2023, 8:15 a.m.

    I think it's wisest to tread Don's 'demonstrations' as entertaining conundrums, if you enjoy hunting out trickery, not as statements of fact. If you don't enjoy hunting out trickery, just ignore them.

  • Members 3952 posts
    April 28, 2023, 8:26 a.m.

    Yes. that is all true for anyone who is aware of his history and what he gets up to.

    But further down the track of time new members to DPRevived who might not be aware of his history here or at dpreview might end up wasting a lot of time if he tries the same things and members who know what he might be doing simply ignore him.

  • Members 2306 posts
    April 28, 2023, 9:55 a.m.

    do think taking an image at iso 100 and iso 4000 of your kitchen is rocket science ? im glad im me. do you guys actually take test images ?

  • Members 2306 posts
    April 28, 2023, 10:05 a.m.

    back peddling are you both after your exposure triangle theory hit a brick wall 😁 i have so much more info would make you and Bobs head spin on the whole history of photography. You guys just preach everyone else's info without doing your own research.

  • Members 3952 posts
    April 28, 2023, 10:07 a.m.

    No, it's quite easy just like faking and editing them to suit an agenda would be if someone wanted to.

  • Members 2306 posts
    April 28, 2023, 10:08 a.m.

    childish accusations