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Detector data - image versus raw data

Below is a picture of pedestal values of the first 10 events for 'Quad3'. The data is recorded in a 3-d shape of (4,......). For each of these pixels, we have x,y and z arrays for their relative center positions. It is possible to setup the geometry so that these x,y,and z values can be used with their absolute values, although we usually do not do that. 

When you now want to display this data on a 2-d screen, we assign each pixel and ix and y values. You can see that in this example, the data in the top left ASIC seems to be aligned while you can see that the bottom left ASIC data is rotated relative to that and this shows up as a discontinuity when placing the values on a grid. This discontinuity is what you can see in the tiff files. Most of the time, this does not matter a lot, but if you care to use the most precise data available, you should use the pixel data and their pixel-center positions rather than the assembled 2-d images.

Image Added<I will add an example picture where you can see the effect of going from 3d to 2-d space

One time processing versus psana use (standard smalldata workflow)

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