Difference between revisions of "2645: The Best Camera"

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(touch-up, re-added bit about orbit)
(Explanation: link showing JWST orbit, grammar)
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''The Best Camera Is The One That's With You'' [https://www.goodreads.com/book/show/6921300-the-best-camera-is-the-one-that-s-with-you] is a book by photographer Chase Jarvis, celebrating mobile phone cameras, not for their photographic or technical quality but rather for the fact that you always have it when an interesting subject appears. This is advice often given to novice photographers, sometimes with the slight change "The best camera is the one you use most." A cheap {{w|Nikon Coolpix}} camera can be better than a professional {{w|Canon EOS}}, simply for the fact it is lightweight enough to be taken on ''every'' voyage you'll make. A fancy expensive camera that isn't at hand for you to use is of no value for taking pictures.
 
''The Best Camera Is The One That's With You'' [https://www.goodreads.com/book/show/6921300-the-best-camera-is-the-one-that-s-with-you] is a book by photographer Chase Jarvis, celebrating mobile phone cameras, not for their photographic or technical quality but rather for the fact that you always have it when an interesting subject appears. This is advice often given to novice photographers, sometimes with the slight change "The best camera is the one you use most." A cheap {{w|Nikon Coolpix}} camera can be better than a professional {{w|Canon EOS}}, simply for the fact it is lightweight enough to be taken on ''every'' voyage you'll make. A fancy expensive camera that isn't at hand for you to use is of no value for taking pictures.
  
However, in this case "the best camera" refers to the {{w|James Webb Space Telescope}} (JWST), the spacecraft depicted in the third frame. It can be considered a camera because it takes pictures. The first pictures taken by the telescope were released on 11-12 July 2022, days before this comic was published [https://www.nasa.gov/webbfirstimages]. The pictures from JWST show objects as they were 13 billion years ago, which was unprecedented. The title text references {{w|Lagrange Point|Lagrange Point 2}} (L<sub>2</sub>), one of the five places in space where something can be stationary relative to two celestial bodies (here, Earth and Sun), and which the JWST revolves around. The Sun-Earth L<sub>2</sub> point was chosen for JWST because orbiting a Lagrange point uses very little fuel for trajectory corrections, and it avoids the problem the {{w|Hubble Space Telescope}} had - orbiting around the Earth, it had a short observation window per revolution. The HST could be used for about 55 minutes of every 95-minute orbit for targets not sufficiently above or below the orbital plane. In addition, the telescope orbits around L<sub>2</sub>, rather than being stationed exactly at it, to avoid shadows from the Earth and Moon that would cause temperature variations in the instrument.[https://www.jwst.nasa.gov/content/observatory/sunshield.html]
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However, in this case "the best camera" refers to the {{w|James Webb Space Telescope}} (JWST), the spacecraft depicted in the third frame. It can be considered a camera because it takes pictures. The first pictures taken by the telescope were released on 11-12 July 2022, days before this comic was published [https://www.nasa.gov/webbfirstimages]. The pictures from JWST show objects as they were 13 billion years ago, which was unprecedented. The title text references {{w|Lagrange Point|Lagrange Point 2}} (L<sub>2</sub>), one of the five places in space where something can be stationary relative to two celestial bodies (here, Earth and Sun), and which [https://space.stackexchange.com/a/57378 the JWST revolves around.] The Sun-Earth L<sub>2</sub> point was chosen for JWST because orbiting a Lagrange point uses very little fuel for trajectory corrections, and it avoids the problem the {{w|Hubble Space Telescope}} had orbiting around the Earth, allowing only a short observation window per revolution. The HST could be used for about 55 minutes of every 95-minute orbit for targets not sufficiently above or below the orbital plane. In addition, the telescope orbits around L<sub>2</sub>, rather than being stationed exactly at it, to avoid shadows from the Earth and Moon that would cause temperature variations in the instrument.[https://www.jwst.nasa.gov/content/observatory/sunshield.html]
  
 
==Transcript==
 
==Transcript==

Revision as of 23:23, 13 July 2022

The Best Camera
The best camera is the one at L2.
Title text: The best camera is the one at L2.

Explanation

Ambox notice.png This explanation may be incomplete or incorrect: Created by an AMATEUR PHOTOGRAPHER - Please change this comment when editing this page. Do NOT delete this tag too soon.
If you can address this issue, please edit the page! Thanks.

The Best Camera Is The One That's With You [1] is a book by photographer Chase Jarvis, celebrating mobile phone cameras, not for their photographic or technical quality but rather for the fact that you always have it when an interesting subject appears. This is advice often given to novice photographers, sometimes with the slight change "The best camera is the one you use most." A cheap Nikon Coolpix camera can be better than a professional Canon EOS, simply for the fact it is lightweight enough to be taken on every voyage you'll make. A fancy expensive camera that isn't at hand for you to use is of no value for taking pictures.

However, in this case "the best camera" refers to the James Webb Space Telescope (JWST), the spacecraft depicted in the third frame. It can be considered a camera because it takes pictures. The first pictures taken by the telescope were released on 11-12 July 2022, days before this comic was published [2]. The pictures from JWST show objects as they were 13 billion years ago, which was unprecedented. The title text references Lagrange Point 2 (L2), one of the five places in space where something can be stationary relative to two celestial bodies (here, Earth and Sun), and which the JWST revolves around. The Sun-Earth L2 point was chosen for JWST because orbiting a Lagrange point uses very little fuel for trajectory corrections, and it avoids the problem the Hubble Space Telescope had orbiting around the Earth, allowing only a short observation window per revolution. The HST could be used for about 55 minutes of every 95-minute orbit for targets not sufficiently above or below the orbital plane. In addition, the telescope orbits around L2, rather than being stationed exactly at it, to avoid shadows from the Earth and Moon that would cause temperature variations in the instrument.[3]

Transcript

Ambox notice.png This transcript is incomplete. Please help editing it! Thanks.
[Each panel features an image of space, with text printed in white at the top of each panel. The first panel says:]
They say the best camera is the one you have with you.
[A panel showing more stars and galaxies visible.]
It turns out
[A panel showing even more stars and galaxies visible. At the center of the panel is an outline drawing in white of the James Webb Space Telescope.]
they're wrong.


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Discussion

Removed the part about L2 being in Earth's umbra. Although this is true, the JWST is not actually at L2; it revolves around L2, specifically to avoid being in the Earth's umbra (and the moon's) and therefore avoid changes in temperature. DKMell (talk) 17:52, 13 July 2022 (UTC)

Does anyone know whether they use SAOImageDS9 or Astropy to make full color images? Both are listed under post-pipeline tools. General instructions are in this paper but it's not a software tutorial, and it doesn't mention un-redshifting very distant objects like in Dr. Becky's video (and which they didn't do completely for the deep field because the lensed galaxies were actually red.) 172.70.206.213 05:35, 14 July 2022 (UTC)

Can we use the published image data files to produce a SMACS 0723 image with only the far-redshifted, lensed objects? 172.70.211.36 16:01, 14 July 2022 (UTC)
There is a tutorial at https://www.galactic-hunter.com/post/jwst-data by a guy who uses PixInsight, which unlike DS9 and Astropy is commercial (€230) but a anyone can use it free for 45 days. I think the instructions for what you want to do are at https://pixinsight.com/tutorials/PCC/index.html and the data is here for SMACS 0723.
You can use Imviz to colorize too. 172.70.207.8 00:44, 16 July 2022 (UTC)

When discussing biosignatures of exoplanets, should we draw the distinction between ozone and water? 162.158.106.113 11:58, 14 July 2022 (UTC)