Archived posting to the Leica Users Group, 2007/09/10
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Hi Steve. My information was from an LFI article as I've only shot about 30 frames with an M8. LFI does say that the camera does better at discriminating darker tones. Purportedly this agrees with human vision characteristics. The nature of the A/D converter is that half of the tonal values are used to delineate the first, brightest bit, then half the remainder for the next, etc etc, down to very few obviously for the last (darkest) bit. So I was trying to say that you want to use the complete possible tonal range of the brightest bit or you are starting with a lot less tonal values than the possible maximum. Naturally there is a great deal of manipulation of the recorded values in further processing and purpose, so it may be less important. The files that I have are extremely robust and tonally smooth. Whatever you're doing is making good images anyway. I can see that -.3EV will make clipping less likely. The M8 that I borrowed was setup that way too. Practical performance is what counts, I just am very interested in the mechanics as well. It is inevitable that there is a digital M in my future. Cheers Hoppy -----Original Message----- Subject: Re: [Leica] Steve Unsworth PAW - week 33 Hi Hoppy It's my understanding that the compression algorithm isn't linear, and more of the values are allocated to the shadows than the highlights, so the usual 'expose to the right' advice isn't as relevant. Steve On 10/9/07 01:56, "G Hopkinson" <hoppyman@bigpond.net.au> wrote: > According to Leica, yes 14 bit, with 2 of 16 having been discarded due to > noise contamination. > Yes also on the non-linear, and the magic of storing as 8 bit but being > able > to recover the high bit information even though the > file is smaller. > Half of the tonal values are used to resolve the first (brightest) stop. > So you don't want to clip but you do want all of that right side > information. > I think Tina has the right of it in her explanation. _______________________________________________ Leica Users Group. See http://leica-users.org/mailman/listinfo/lug for more information