Archived posting to the Leica Users Group, 1998/11/28
[Author Prev] [Author Next] [Thread Prev] [Thread Next] [Author Index] [Topic Index] [Home] [Search]At 14:58 28/11/98 +0100, Erwin wrote : First of all, Dominique, I am well aware that the edge spread function approach for image analysis, has been developed by Leitz, more to the point by Mr. Thomas from the Leitz Rechenbüro (Optic Design department). Comment : I'm not quite sure Mr Thomas would appreciate your previous valuation :"Let me be quick and mercifully: this 'edge spread width criterion' does not exist". The ethical problem is that, when you criticize a method, there is no way for the defender to answer. On the contrary, when I write that one of your statement is neither fair nor academic, you can reply. As an example, see the answer of a researcher after I criticized his paper : <smaller>From: Tamim Bayoumi <<TBAYOUMI@IMF.ORG> To: pelliss@droit-eco.u-nancy.fr Subject: your paper on a formal model of OCA -Reply Content-Disposition: inline Thanks for the question. I do not think the algebra is written very well, so you confusion is understandable. Sigma squared j - 2 sigma jk + sigma k is the variance of the sum of the two shocks. It rises with the variance of the original shocks and falls with their covaraince. The root of this is simply the standard error of the sum of the shocks. The half operated on the entire square root, which is why in the last line of the algebra it cancels with the 2 in the 2 phi zero term. Tamim Bayoumi Rm 5-320 </smaller> You wrote : I am not aware that I gun down or condemn "once more" a research or a method which has been made by others than you. That's neither fair nor academic.I have clearly stated in all my posts around this evaluation topic, that I know and appreciate the methods used by PopPhoto (in fact I am quite alone in defending the SQF as a valid approch), that I know the MTF measurements by ColorPhoto, Photodo and Chasseurs. Comment : in a previous message (Date: Mon, 23 Nov 1998 23:49:03) you wrote exactly the opposite : "BTW: PopPhoto uses this Ealing measurement apparatus too. Most Lugmembers are not satisfied with or convinced that the popphoto results are meaningfull. So here we have at least four companies (popphoto, cdi,photodo, leica) using the same testing equipment. Why should we believe cdi or photodo while we disbelieve popphoto". You wrote : Now that was the explanation demanded by you. Eric does not want me to take things personally . Still I feel a bit annoyed by your tone: "gun down" "not fair or academic" especially as these accusations are made without any knowledge of my way of work or background. Comment : I asked you previously your methodology. You wrote : Also your demand: "(why ? I'm waiting for a rational explanation)" sounds quite agressive to me. Why should I have to explain indepth my statements to you where you never have given any explanation about your statements or claims besides citing other sources. Comment :I beg your pardon, Sir, but YOU are the first to impeach. I've NEVER charged Chasseur d'images, Photodo, Popphoto or Erwin Puts with misusing MTF analysis. I think that the more tests there are, the more consumers will be informed and will become hard to please with idiotic ad. So you have your place among the testers and I recognize that I appreciate your work and your Website...as I appreciate Chasseur d'images..etc. Dominique Pellissier