Quote Originally Posted by Bill Burk View Post
0 is really a logarithm and it's arithmetic value is "1". It's not arithmetic "No Exposure".
Exactly! However, making an "exposure" with a lens cap IS an arithmetic "No Exposure," and cannot be expressed as a log exposure value (try to find the log of zero). Therefore the lens-cap exposure cannot be graphed on this chart. I think this was Michael's only serious issue, apparently a misunderstanding as Henry didn't actually say to do this.