Resolution: Slight improvements are possible

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From other materials here, you should know things about the native resolution from these various surveys. You should have a gut-level understanding now that you can't get more information out of the image than was recorded by it in the first place.


I have swept some things under the rug. IRAS data was so interesting, and it was going to be so long before astronomers got any more data in those wavelengths on that scale, that very clever people got to work on how to get even more information out of IRAS data. Imagine those big IRAS pixels scanning over a patch of warm sky. The next time the spacecraft scans that same patch of sky, the pixels are offset a little bit from where it was on the last pass, and consequently the fluxes it measures are just a little different. Same for the next scan, and the next. If you have lots of scans over the same region, each of which are at slightly different positions (that's important), you can recover a little bit of the information on a slightly higher (better) spatial resolution. This page has some general information on the specific application of this method to IRAS, called "Hi-Res", along with example pictures. It uses the Maximum Correlation Method (MCM; H.H. Aumann, J.W. Fowler and M. Melnyk, 1990, AJ, 99, 1674). It is computationally expensive (meaning it takes a while to run), and requires lots of individual tweaking and customization, so it has not been run (blindly) over the whole sky. The degree of improvement is related to the number of scans; as for WISE, the number of passes is a function of the ecliptic latitude, so just running Hi-Res doesn't get you a specific improved resolution. Hi-Res got famous in the context of IRAS. People have developed ways to run this kind of algorithm on WISE and even Spitzer data, but we're not going to try and use it, as there are no particularly user-friendly interfaces to it (at least at the level we would need), and the incremental benefit we'd gain from this probably outweighs the work it would take to get there.

Note - critical to making this process work is that the camera moves between scans to slightly different positions, and the source it is looking at is not changing in brightness. Will this process work on security camera videos?