I'm still not sure how to interpret Lonelyspeck's Google Sheet's lens astro score
https://docs.google.com/spreadsheet/ccc?key=0AomVJ2lbrwb1dDRGeHJOaVZfYnlFR2ZDTFNlSnk2emc&usp=sharingI mean, on paper, I get that it's a synthetic score and comes with its limitations, but as it's a synthetic score, it's also quite helpful in comparing different focal lenghts and apertures. 2000 will be 2x better than 1000 for this application.
But I'm surprised at how much 24mm is favored compared to UWA. Though it's true the best milky ways I've seen are more often than not from 24mm f1.4 lenses, so there's probably some truth to it.
Still, to take an extreme example, I'm not sure why a,20mm f1.8 lens with its 25sec of exposure time (rule of 500 is shit but whatever) doesn't have the same score as a 10mm f2.8 score that can expose for 50sec. I mean, sure, you lose 1 full stop, but you can expose 2x longer, so it should compensate. No?
