There is a school of thought that says that, if you have to pick one, MTF10, the spatial frequency where the modulation is 10%, is a more appropriate metric for imaging system sharpness, since more images will undergo capture sharpening, and MTF10 on the unsharpened image will translate to a higher modulation after sharpening. One… [Read More]

I ended a post a couple of days ago on an intellectually-unsatisfying note: So, in general, the answer to the question, “Would you like more lens resolution or more sensor resolution” is: “Yes.” Which would do you the most good depends on where you are on the 3D surface in the first graph. In this… [Read More]

I ran the curves from yesterday’s post for the simulated Zeiss Otus 55mm f/1.4 lens. MTF50, cycles/picture height, in three dimensions with no AA filter: In two dimensions, with f-stop as the horizontal axis: You can see that there is not much improvement as we go from a pitch of 2.4 um to one of… [Read More]

Now that I’ve got a fair amount of confidence in the MTF analysis, I went back to the model of the diffraction-limited lens, and ran a set of simulations at various f-stops and sensel pitches. Here’s a 3D look at the results, with MTF50 cycles/picture height the vertical axis, sensel pitch in um coming towards… [Read More]

Yesterday I went back and looked at some of the simulation results, and grew suspicious that there were problems with the way the simulated camera was sampling the simulated target. As I dug deeper, I started to question some of my original assumptions, and started experimenting with changes. What I ended up with is close… [Read More]