The spatial resolution matters a lot when comparing images across wavelengths, or even just between telescopes.
Most coherent, developed, tested materials
- Resolution Overview -- Dr. Luisa Rebull (created 2010, last substantially updated 2017)
- Resolution and YSOs, examples and exercises (used to be integrated with the overview above) -- Dr. Luisa Rebull (created 2010, last substantially updated 2017)
- Resolution: Calibrating your expectations - worksheet addressing what sizes you expect to find in the sky and in images -- Dr. Luisa Rebull (2020 but refined over nearly 10 years)
- Resolution: Slight improvements are possible -- Dr. Luisa Rebull (2020 but refined over nearly 10 years)
Less coherent, developed, tested materials
Useful Related Links
Article on resolution from Bad Astronomy - this is in the context of debunking the moon hoax, but resolution issues are important for his discussion.
Another resolution discussion from Bad Astronomy.
Why can Hubble get detailed views of distant galaxies but not of Pluto? by Emily Lakdawalla at the Planetary Society
xkcd on angular size (link is actually to the explainer, which has more information than just the comic.)