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Message: <blockquote data-quote="Vespobuteo" data-source="post: 3322882" data-attributes="member: 120830">The TF experiments were done in a time (100 years ago) when the transmission of a binocular was about 50-60%, and transmission of the blue spectrum even lower, and as Holger mentions in the article (linked above), experiments were biased towards higher mag bins.Quality dimensions will always be lost when you try to put a single number on a complex issue.TF might be an example of that.*It's like putting a gourmet dinner in a blender and then serve it in a can with a spoon...talk about not taking the observer into account...*Just to clearify:I have no problem with the underlying facts on vision in low light etc,it's the model/formula (TF) I have problems with,an 8x56 (with lower TF) will actually perform better than a 12x42 (with higher TF) if you are around 30 years or happen to have large pupils (see Holgers paper for the example).So the bottomline is that TF might produce false predictions on binocular performancefor a lot of people.</blockquote>