Yes, hours vs days, which makes them a lot more impressive if you know a bit about photography. I wanna see what this thing is able to do with a 10 days exposure. Let it loose.
>I wanna see what this thing is able to do with a 10 days exposure. Ever seen a solid white square? =) As with all things, it totally depends on what's being imaged. Exposing the Orion Nebula for 10 days would result in a totally over exposed image looking like a solid white square.
I trust astronomers to know how to set the exposure.
I want the Webb focusing 10 days on a patch that looks pitch black on Hubble’s 10 days deep field
Aesthetically, I like the Hubble images better, they are more painterly and colorful. However there is no doubt that the JWST contains way more information and is exponentially more valuable.
For the professional (or former professional) astronomers among us, I will make my somewhat amused observation that what people are most paying attention to is not really the distinguishing features of JWST. People seem most impressed by the apparent increase in resolution of the images, which is not from a certain point of view the hardest thing to do . HST might have done that if its instruments had been of differe…
.. and why is infra-red more useful ? Can we see through dust or something ?
Seeing through dust is part of it. Another part is redshift: because of relativity, things moving away from us appear redder (longer wavelength) the faster they’re moving away. That’s the same principle (Doppler effect) as the lower-pitched siren sound as the ambulance drives away. Because the universe itself is expanding, the farther something is from us, the faster it’s moving away relative to us, and the more redshifted it appears to us. And again because of relativity, the oldest objects we can see are the ones that appear farthest away (i.e. their light is just now getting here, after 13 billion years, from 13 billion light years away). Thus, if we want to study the earliest times of the universe, we must study the most redshifted objects—which have shifted all the way out of the visible spectrum and into the infrared. Hence, Webb is an infrared telescope.
For the professional (or former professional) astronomers among us, I will make my somewhat amused observation that what people are most paying attention to is not really the distinguishing features of JWST. People seem most impressed by the apparent increase in resolution of the images, which is not from a certain point of view the hardest thing to do . HST might have done that if its instruments had been of differe…
In the second image it is clear that more of the nebula is visible, isn't this because more wavelengths of light are being detected? In this case an amateur absolutely can appreciate the technical improvements, the IR is mapped to a visible RGB spectrum...
Downvote me to hell, but as a person who has zero understanding of what differentiates Hubble from Webb, the pictures alone just aren't doing it for me. I was excited to see something completely new given 30 years and 10 billion dollars and instead I feel like I'm seeing what looks like an enterprise upgrade and feel slightly disappointed. What am I missing?
Webb isn’t optimized to produce maximally pretty pictures, because most of Webb’s groundbreaking science is not necessarily going to involve pretty pictures. For example, Webb will tell us otherwise-unknowable things about the atmospheric composition of exoplanets—but it will not produce stunning photos of them (too small and far away to look like more than a pinpoint). Webb will tell us discipline-defining things about the cosmological conditions in the very earliest years of the universe—but that doesn’t mean it can show us pictures of the earliest galaxies in the same close-up detail as it could of a nearby galaxy. The latter image, while more breathtaking for us laypeople, would not tell us much of anything new.
With that said, NASA is not unaware of the PR value of pretty pictures (they weren’t the point of Hubble either!) and I have no doubt that we will be getting plenty of them.
They're not lens flares, but they're still an artifact of the system, which is probably what most people mean by "lens flare" anyway, due to lack of a better common term.
According to the Wikipedia definition, I'd say that Webb's artifacts could be classified as "lens flares". >This happens through light scattered by the imaging mechanism itself, for example through internal reflection and forward scatter from material imperfections in the lens. Lenses with large numbers of elements such as zooms tend to have more lens flare, as they contain a relatively large number of interfaces at…
Diffraction spikes are caused before the lens gets involved; improving the lenses cannot remove the spikes (though there may be structures causing diffraction spikes in-between lenses).
The spikes from JWST are primarily caused by the edges of the mirrors and the three support struts.
There likely is some amount of lens flare (though I don't know if it is significant, the optics are Very Good), but the dominant artefact is the diffraction spikes.
> Why does that only come from Webb images? Re-read comment.
"It's hard to look at the Webb images without thinking..." What am I missing?
A charitable interpretation.
You're making the assumption the poster meant they didn't have this feeling before. They might just be repeating that, once again, it's difficult to do this with Webb. Hubble is irrelevant. Anything else is irrelevant. They're talking about the pictures here in front of us.
Question for anyone who happens to be an expert: Is there any way to quantify how much better Webb is independently of the amount of time used to take the exposures? Like, could Hubble achieve the same quality of images as Webb if it was given 100x (or whatever) more time exposure? I'm trying to understand how much the improvement is "speed of convergence" vs. "quality of asymptotic result". (Though... is that even a…
The Hubble image of SMACS was a 10 day exposure, the Webb image was a 24hr exposure and is far superior.
Aesthetically, I like the Hubble images better, they are more painterly and colorful. However there is no doubt that the JWST contains way more information and is exponentially more valuable.
It's kinda like listening to music on vinyl vs. digital.
High quality digital is clearly superior sonically, but vinyl has a dullness around the edges that is so aesthetically pleasing.
I agree that the Hubble images are just pleasant to look at, warm and wonderful.