KrisCarnmarker
New member
John, thanks for that explanation. I may be incorrect, but you are basing your arguments on noise levels, are you not?
Noise levels are obviously not irrelevant, but to me at least, the purpose of ETTR is about tonal gradations more than about noise levels. These two are practically related of course.
If we use the LL article examples, a camera capable of 5 stops DR, with a 12-bit ADC provides 4096 distinct values. 2048 of those are used in the first (brightest) f-stop, 1024 for the next, etc.. Practically, this means I get better tonal gradations at the higher f-stops, which is what we want to exploit.
So, if I go to e.g. ISO 400, do I no longer have those 2048 levels available in the first f-stop any more? This is what I don't understand. Of course, I'm simplifying things, and it may be that although I do still have those 2048 levels, other parameters have worsened and whatever gains I have achieved by ETTR at ISO 400 have been made negligible by the other factors.
Noise levels are obviously not irrelevant, but to me at least, the purpose of ETTR is about tonal gradations more than about noise levels. These two are practically related of course.
If we use the LL article examples, a camera capable of 5 stops DR, with a 12-bit ADC provides 4096 distinct values. 2048 of those are used in the first (brightest) f-stop, 1024 for the next, etc.. Practically, this means I get better tonal gradations at the higher f-stops, which is what we want to exploit.
So, if I go to e.g. ISO 400, do I no longer have those 2048 levels available in the first f-stop any more? This is what I don't understand. Of course, I'm simplifying things, and it may be that although I do still have those 2048 levels, other parameters have worsened and whatever gains I have achieved by ETTR at ISO 400 have been made negligible by the other factors.