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James Webb first images – complete set of high resolution shots now live

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Re: James Webb first images – complete set of high resolution shots now live

#71

Post by jacquesm »

mike10921 wrote: post #53
crhulls wrote: post #15

Here is a Hubble side by side of the deep field for comparison https://www.facebook.com/photo.php?fbid=10159217085846758&se...

Ok to be honest I know it's not cool to admit it, but so far it all looks the same. If someone told me that the Webb picture was taken by Hubble I would not have thought about it for an extra second. I'm hoping that in the future we see pictures of locations and environments that are mind-blowing to the average person who loves space.

The very rough equivalent in computer terms: a 1997 PC computing something and taking a week or so to do it and returning the answer: 3.

The same by the 2022 version: 3.14159265358979323846 in a few milliseconds.

Both the speed of the computation and the resolution of the result are what makes it impressive, not the fact that the nature of the universe does not change fundamentally when viewed across a longer span of time.

It is mind-blowing, but maybe not to the 'average person who loves space'. But if you stop for a bit longer to understand what it took to create that image and what it is that you are actually looking at (the age of the objects involved, their apparent size and the resolving power and temperature of the telescope required to make it) it becomes a lot more impressive.

Re: James Webb first images – complete set of high resolution shots now live

#72

Post by anewpersonality »

sephamorr wrote: post #51
anewpersonality wrote: post #30

Dumb question. Why can’t we focus on a single exoplanet, look for mountains, grass, buildings? Why am I so stupid but isn’t this the obvious thing to do?

There is a fundamental physics limit at play here: the diffraction limit is linear with the aperture diameter and gives an upper bound on the resolution of a telescope. Having a longer exposure doesn't help - that's for resolving very faint objects (more light collected -> higher signal-to-noise). To resolve a building-sized object on an exoplanet, regardless of its intensity, we'd need a telescope the size of the so…

This is a good answer, though incredibly depressing

Re: James Webb first images – complete set of high resolution shots now live

#73

Post by jacquesm »

alberth wrote: post #32

Correct me if I’m wrong, but aren’t most astronomy photos colorized (and not actually such vivid colors in real life).

Absolutely, these objects would be completely invisible when using visible light so it is all false color, just like a FLIR would show you an image of the infra red light emitted by an object by shifting it to a spectrum that you can directly perceive.

Re: James Webb first images – complete set of high resolution shots now live

#74

Post by ceejayoz »

anewpersonality wrote: post #49
throwaway5752 wrote: post #46

Earlier quoted context omitted.

Maybe the link changed, but the 5th link down the page, "July 12, 2022 Release ID: 2022-032", is "Webb Reveals Steamy Atmosphere of Distant Planet in Exquisite Detail ", link is https://webbtelescope.org/contents/news-releases/2022/news-2...

Thats a spectograph

Yes, and if we do a spectral analysis on a small rocky exoplanet and find a bunch of oxygen, that tells us a lot more exciting information than the 2x2 pixels you might get from an image of it.

Re: James Webb first images – complete set of high resolution shots now live

#75

Post by ceejayoz »

mike10921 wrote: post #68
ceejayoz wrote: post #56

Earlier quoted context omitted.

The difference is in a) the details and b) the length of time the telescope has to gather light to get the photo. JWST got the photo in hours when Hubble took weeks, and there's easily 10x as many objects in the JWST shot. JWST can thus observe much fainter and much more distant objects - galaxies billions of years old, exoplanets, etc., and it can do more of it .

Of course, I get it, but we are allowed to admit that to the average person so far it looks like more of the same.

I'm honestly not sure how you someone can look at those two photos side-by-side and think they're the same. Hubble's is like slapping a 360p cam rip on a 4k TV.

Re: James Webb first images – complete set of high resolution shots now live

#76

Post by capableweb »

mike10921 wrote: post #68
ceejayoz wrote: post #56

Earlier quoted context omitted.

The difference is in a) the details and b) the length of time the telescope has to gather light to get the photo. JWST got the photo in hours when Hubble took weeks, and there's easily 10x as many objects in the JWST shot. JWST can thus observe much fainter and much more distant objects - galaxies billions of years old, exoplanets, etc., and it can do more of it .

Of course, I get it, but we are allowed to admit that to the average person so far it looks like more of the same.

Unless you know what you're looking at, most if not everything looks mundane. It's only with perspective that we can grasp the beauty of things like these, or just other things, like ants.

To most people, ants are just an annoying bug. But to scientists (and curious non-scientists), ants are endlessly fascinating creatures. Together with scientists who speak to "common folk", even they can understand the beauty in how ants work.

That's why outreach and education is so important. And sometimes the beauty doesn't come from the direct thing (like these images, although I'd argue they are beautiful by themselves too) but from the indirect implication of the thing (time to acquire the picture, the data gathered to "draw" the picture, the community for even enabling this picture from being drawn and so on).

Re: James Webb first images – complete set of high resolution shots now live

#77

Post by whiteboardr »

Watching the livestream i was more than surprised, that color correction actually happens in Photoshop.

Also, there seem to be multiple layer-masks involved for specific regions and objects.

I get that you can shift and composite color, based on hue, apply filters etc, but: Photoshop?

Curious if anyone can explain, that what we see is actual science or some touched up version of objects in our universe.

p.s.: What struck me the most is the absence of noise, especially for the deep field photo. Hubble took many exposures over weeks, which normally would allow for reliable reduction of noise, webb took some shots over the course of hours and there’s hardly any noise to see. Weirdest part is seeing them just “healing brushing” away some dots - how is the decision process on altering images like that?

(edit for typos)

Re: James Webb first images – complete set of high resolution shots now live

#78

Post by jacquesm »

leeoniya wrote: post #4

the Southern Ring Nebula (MIRI Image) is bizarrely very low res? https://webbtelescope.org/contents/media/images/2022/033/01G...

It's the effect of the wavelength of far infrared light being quite a bit longer.

Think of a reduction to extremes: if you have a sensor that is a centimeter square and you're trying to 'catch' a wave that is a meter long there is a fair chance the sensor will be bypassed entirely, but if you are trying to catch millimeter waves your sensor will be easily able to capture the photons.

The most practical example of this effect is the size of radio antennae, they get longer as the wavelength gets longer.

Re: James Webb first images – complete set of high resolution shots now live

#80

Post by wolfd »

quaintdev wrote: post #48
crhulls wrote: post #15

Here is a Hubble side by side of the deep field for comparison https://www.facebook.com/photo.php?fbid=10159217085846758&se...

A GIF comparing both Hubble and JWST https://i.redd.it/9uyhwijeo0b91.gif

I made this page (posted in another thread yesterday) because I was rather underwhelmed by the .gif. I think the page shows in much better detail the difference between the telescopes' capabilities.

https://blog.wolfd.me/hubble-jwst/

(If you're on mobile, you should be able to zoom in and still use the slider)

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