Archived posting to the Leica Users Group, 2000/01/24
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]Jonathan Borden wrote, in part: > > Are you suggesting that neither employs statistics? I don't know much about > either but I recall that there is at least a statistics based branch of > anthropology. > Most (in fact all) literature I've read on anthropology stresses the importance of qualitative descriptions and analysis. Numbers don't enter in to it, essentially. Statistics certainly haven't, in what I've read, but I admit I haven't studied anthropology extensively. Besides, what is statistics if not just a convienent shorthand for mistaking correlation for casality? > > Every field of science *does* have experiments which produce observations. > The English language is somewhat problematic when it comes to the word "science". Basically, it can have two meanings: (1) classic, hard-core, quantitative, natural science (physics etc.) (2) a scientific approach to research The easy way is to exclude everything which isn't physics as "not being scientific". Unfortunately, this does little to explain how we can learn anything about the world around us in fields that physics is unconcerned with. The more difficult is to realize that nothing is set in stone. Observations depend on an observer. The very nature of observing depends upon being able to recognize significance, which in turn depends upon how we view the world (ontology) and what we consider to be worthwhile knowledge (epistemology). If you change those beliefs and understandings, your observational data and analysis will also change. You mentioned yourself: "...assuming you believe in systems theory". That's the key, it's a theory. I need to understand, when reading lens tests by those who employ MTF measurements (or any other test or evaluation, for that matter), what the assumptions are that those tests rest upon (such as systems theory and well focussed images) to understand what they are (and are not) testing. I then employ that knowledge, along with the knowledge of what *I* believe, understand and have experienced, to draw conclusions about suitability. Even if the concept of bokeh is captured by the MTF theory, every single practical MTF test I have ever seen has looked at how the lens renders something that it is focussed upon (usually at infinity). Not how it renders something that it is *not* focussed on, either infront of or behind the plane of focus. We observe what we know to look for. M. - -- Martin Howard | "Very funny Scotty. Now beam down Interactive Systems Designer | my clothes." email: mvhoward@mac.com | www: http://mvhoward.i.am/ +---------------------------------------