Lens Aberration in Superzooms?

Started Nov 28, 2013 | Discussions thread
OP Stephen Barrett Contributing Member • Posts: 683
Re: Lens Aberration in Superzooms?

Your tests sound very interesting, Ian.

If your white area is made small enough, you will be measuring the Point Spread function (PSF). Theoretically, after normalizing it, you can do a 2-dimensional Fourier transform to obtain the MTFs in every direction simultaneously. It is probably not really worth the effort to do that because there may not be enough pixels to make the statistical errors small enough (unless you average a lot of tests). If you sum over lines or columns in your spreadsheet, that will give you the Line Spread Function (LSF) which is what I was measuring, so we have been doing very similar tests. I look forward to seeing some of your results when you are ready to post them.

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