How come this isn't as good as in the paper?


The image in the recent paper is much better than the one on legacysurvey.org - how come?

It is likely that this really cool lens was found with the survey, and scientists found it interesting so they used a better telescope to focus specifically on it. For example, when a somewhat nearby galaxy is discovered, maybe in a survey or idk, they then look at it with hubble

Can you post a link to the paper, so that we can have a look at the text?
Maybe they used a larger telescope, as @NateSmartkid said. Or they used a different technique, which is usually described.

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Here is the paper. There is no mention of using any other telescopes.

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I think that image was created by the press folks at NOIRLab. You can see that the background is much blacker – they’re stretched it harder and suppressed the sky level. Perhaps also deconvolved, or maybe chose the clearest of the available images.

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In the paper from Huang et al. it looks just like the image you posted:
Figure 10, lower right:

“The fourth one (DESI-090.9854-35.9683) is a spectacular system: at least four lensed sources at different redshifts are apparent, including a quad (1, white arrows), a “broken” long arc (2, yellow arrows), one red arc near the core of the group (3, green arrow), and a giant red arc at approximately 14′′ away from the lens center (4, red arrow).”

~

Image link at NOIRLab website:

I would not call it “better”. For my taste it is pushed a bit too much to the limits.

Aha! The NOIRLab site has finally solved the riddle - it’s SIMULATED! I was wondering how they had managed to get so much extra detail in the central galaxy and in the arcs simply by enhancing the original data - the answer is they made it up! Tut.

…and I think it’s a bit naughty of them not to identify that in a publication. Bad form.

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Oh, did not notice this.
In the “Colors & Filters” I did read “Víctor M. Blanco 4-meter Telescope”, so I assumed it was real. I wonder how they managed to get the position of each galaxy and lens arc correct in a simulation. Never came across something like this.