FZ200 Diffraction Limit - Panasonic Tech Service

Started Aug 27, 2013 | Discussions thread
Stephen Barrett Contributing Member • Posts: 683
Re: Does the Panasonic FZ50 violate the laws of Physics?


Thanks very much for your kind remarks. I must say that I am somewhat confused by your statement that you thought that the letter E looked fairly legible most of the time and your question about a sentence sample at one pixel per line width. I assume that the image for which you state that most of the Es are legible is the one for which the Es have a line thickness of 1.5 pixels.


When I said that the E looked legible most of the time with 1 pixel per line width, I was referring to your greyscale simulation, not the actual camera test. There are 11 Es at different heights with respect to the pixels and 10 of them are recognizable as Es. Only the middle one lost its arms and looks like a letter I.

The question that I asked was stupid, as a result of posting in a hurry before I had to go somewhere. What I had in mind was some telephoto tests that I did with my Canon SX30, resolving about 30 microradians (~9% MTF line-pair resolution using the USAF test chart). At the same time, I did some tests with printing "The quick brown fox jumped over the lazy dog." using various fonts. With simple fonts, the printing became legible at a height corresponding to 55 microradians. This is probably a poor test because I knew the words ahead of time and, even if I that were not the case, one could probably guess a lot of the words from a few legible letters and the shape of the word. So your tests with a single letter make more sense.

In spite of my the obtuseness of my question, I think that you answered it when you said that 1.4 pixels per line width might be enough for intelligibility, but not 1.3.
Thank you.

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