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Compare Webb's Images to Hubble

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11–20 of 254 posts

Re: Compare Webb's Images to Hubble

#11

Just needs to include exposure time differences and this is perfect. Glad to witness the power of this fully armed and operational battle station.

It's my understanding that Webb used much shorter exposure times than Hubble, correct?

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.

Re: Compare Webb's Images to Hubble

#15

Thank you so much!!! I really wanted to see the difference side by side and this was an even better presentation. Really cool!

Just to be clear I did not create this website, I just saw it on reddit. All credits to the original author: https://www.reddit.com/r/woahdude/comments/vxeeqo/i_made_a_t...

Re: Compare Webb's Images to Hubble

#16
post #4

Here's a backyard telescope versus Webb: https://twitter.com/AJamesMcCarthy/status/154694183270093209... More comparisons on Twitter, some zoomed in: - https://twitter.com/Batsuto_/status/1546899241880240128 - https://twitter.com/Batsuto_/status/1546900387931766784 - https://twitter.com/JBWillcox/status/1546881033597075457 - https://twitter.com/jason4short/status/1546626672488632321 I'm not a physicist, so I've only…

thank you very informative.

Re: Compare Webb's Images to Hubble

#19
post #4

Here's a backyard telescope versus Webb: https://twitter.com/AJamesMcCarthy/status/154694183270093209... More comparisons on Twitter, some zoomed in: - https://twitter.com/Batsuto_/status/1546899241880240128 - https://twitter.com/Batsuto_/status/1546900387931766784 - https://twitter.com/JBWillcox/status/1546881033597075457 - https://twitter.com/jason4short/status/1546626672488632321 I'm not a physicist, so I've only…

The spikes are caused by diffraction of light around the struts supporting the secondary mirror. Hubble has 4 supports for the secondary mirror. JWST has 3 support for the secondary mirror, which because...physics (I don't know I'm not an optics guy)...manifests as 6 diffraction lines.

https://en.wikipedia.org/wiki/Diffraction_spike

EDIT: It may be caused by both the diffraction spikes from the supports struts and the shape of the mirror and aperture. I'm not really sure. The JWST images also seem to have two additional small spikes that look more like the diffraction pattern from a single strut, which could also be a support strut for a stop further down the optics chain.

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