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

webbtelescope.org

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

#23

Post by DiogenesKynikos »

fumblebee wrote: post #11
leeoniya wrote: post #4

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

Wow you're right, huge difference in the sizes of the "full res" images: > MIRI: Full Res, 1306 X 1133, TIF (1.78 MB) [1] > NIR Cam: Full Res, 4833 X 4501, TIF (24.06 MB) [2] Maybe it's a mistake, they suggest it should offer an "incredible amount of detail": This Mid-Infrared Instrument (MIRI) image also offers an _incredible amount of detail_, including a cache of distant galaxies in the background. [1] https://web…

MIRI works at longer wavelengths than NIRCam, so its angular resolution is lower (longer wavelengths mean more diffraction). It also has a smaller field of view.

Those two factors mean that it has fewer pixels per image.

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

#26

Post by ceejayoz »

historynops wrote: post #10

A lot of the pictures have some bright stars with 6 long lens flare like points coming out of them in a consistent pattern. Is that because of the hexagonal shape of JWT's lenses/mirrors?

It's not the mirrors, it's the three struts supporting the reflector.

Hubble shows four spikes because it has two struts.

https://bigthink.com/starts-with-a-bang/james-webb-spikes/

https://www.universetoday.com/155062/wondering-about-the-6-r...

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

#27

Post by throwaway5752 »

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...

My understanding is that it is also 12-13 hours of exposure for the Webb image vs weeks for Hubble.

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

#29

Post by rbliss »

historynops wrote: post #10

A lot of the pictures have some bright stars with 6 long lens flare like points coming out of them in a consistent pattern. Is that because of the hexagonal shape of JWT's lenses/mirrors?

Yes, it's a combination of both the primary mirror and struts. The JWST website has a very helpful infographic explaining: https://webbtelescope.org/contents/media/images/01G529MX46J7...
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