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Artemis II crew take “spectacular” image of Earth

bbc.com

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Re: Artemis II crew take “spectacular” image of Earth

#221

Post by hdivider »

boca_honey wrote: post #219
1zael wrote: post #202

How are people still flat-earthers after stuff like this

This photo could be easily faked. I don't believe the Earth is flat, but I also don't think everybody on the planet should be 100% on one side of a discussion. Even if flat-earthers are kinda dumb, I think it's worse to force everyone into intellectual submission just because you're "right".

Even if clearly one side is correct without any doubt whatsoever, beyond any question? Such as 2+2=4 -- we should accept a situation where some people insist this is not true? It seems irrational.

Re: Artemis II crew take “spectacular” image of Earth

#222

Post by firefoxd »

Fun question: What time was this taken?

The exif includes time, but not time zone. They are not quite at the moon, and Lunar Time is under active development but not official. Also clocks tick slower under the moon's weaker gravity. (Or is it faster?)

Anyway, what time was this taken?

Re: Artemis II crew take “spectacular” image of Earth

#223

Post by GorbachevyChase »

Sharlin wrote: post #58
dylan604 wrote: post #47

Earlier quoted context omitted.

Who said you can't capture stars in space? What do you think the purpose of Hubble, JWST, etc are? There's also plenty of imagery taken from ISS that clearly show stars. I've definitely seen Orion in some of that imagery and it put a different perspective on the size of the constellations when seen from that angle.

I referred to the common question (or accusation) of why there are no stars in, say, the Apollo photos taken on the moon. The answer is, of course, that you can't see stars if you're exposing for something bright and sunlit, like the day side of Earth, or the lunar surface.

Of course. But they are not visible in the Chang’e photos on the dark side either. I think in the interview of the astronauts following the first Apollo Mission, a reporter asked for a confirmation that the stars were not visible because of “the glare” (an interesting question in itself). The explanation given was that the stars were not visible with the eye, but were visible with “the optics“.

Re: Artemis II crew take “spectacular” image of Earth

#224

Post by jen729w »

porphyra wrote: post #120
hannesfur wrote: post #73

Looking at the EXIF (with exiftool) for the image uploaded by NASA ( https://www.nasa.gov/wp-content/uploads/2026/04/art002e00019... ), apparently this was taken by a Nikon D5 with an AF-S Zoom-Nikkor 14-24mm f/2.8G ED and developed with Lightroom. It also seems like very little was done in Lightroom. Amazing... I dumped the whole EXIF here: https://gist.github.com/umgefahren/a6f555e6588a98adb74eed79d...

I'd have probably shot it wide open at f/2.8 rather than cranking the ISO up to 51200. Incredibly impressed at the steady hands for a sharp image at 1/4 s shutter speed though! Maybe they just let the camera float in space with the mirror up, triggering it remotely.

You might misunderstand how ISO works on digital cameras. (I did.)

https://www.youtube.com/watch?v=ZWSvHBG7X0w

Re: Artemis II crew take “spectacular” image of Earth

#227

Post by chainingsolid »

rafram wrote: post #133
to11mtm wrote: post #98

Earlier quoted context omitted.

... My only curiosity, and yeah I know orders of significance etc... Buuuuut I wonder why they didn't consider a Z5[0][1] and the Z mount 14-24, or the Z5 with an adapter for the F mount 14-24.... There's at least a pound of weight savings on the table. Specifically, I wonder if it's a fun reason? i.e. it would be interesting if there was a technical reason like 'IBIS fails miserbly' or 'increased sensor resolution a…

When you're riding a rocket that weighs 3.5 million pounds...

Mass higher up the rocket costs several multiples more mass in propellant and propellant handling lower in the rocket. And the more deltaV you want the higher the multiplication. (If I remember right some weight issues of some kind on the Apollo capsule and or lander required a common bulk head in the first stage to make up the performance loss!)

However cameras probably fall into the variance in astoraunt weight somewhat.

Re: Artemis II crew take “spectacular” image of Earth

#228

Post by krapp »

boca_honey wrote: post #219
1zael wrote: post #202

How are people still flat-earthers after stuff like this

This photo could be easily faked. I don't believe the Earth is flat, but I also don't think everybody on the planet should be 100% on one side of a discussion. Even if flat-earthers are kinda dumb, I think it's worse to force everyone into intellectual submission just because you're "right".

>I think it's worse to force everyone into intellectual submission just because you're "right".

I think it's worse to consider the acceptance of reality as being "forced into intellectual submission" and to use scare quotes around "right."

There are discussions that everyone on the planet should be 100% on one side of and this is one of them. It is literally just wasting everyone's time to entertain the premise that opinions to the contrary hold any value.

Re: Artemis II crew take “spectacular” image of Earth

#229

Post by chainingsolid »

to11mtm wrote: post #152
rafram wrote: post #133

Earlier quoted context omitted.

When you're riding a rocket that weighs 3.5 million pounds...

Is that the Rocket or the Craft+Mission payload? My understanding is it's on the order of 5-10 pounds of rocket juice to get one pound of something to LEO, thus the question.

At 3.5 mil pounds that has to be the full rocket. But quick [1]googling is giving an even higher total mass number...

1. https://www.nasa.gov/wp-content/uploads/2026/01/sls-5640-sls...

Re: Artemis II crew take “spectacular” image of Earth

#230

Post by deathanatos »

jen729w wrote: post #224
porphyra wrote: post #120

Earlier quoted context omitted.

I'd have probably shot it wide open at f/2.8 rather than cranking the ISO up to 51200. Incredibly impressed at the steady hands for a sharp image at 1/4 s shutter speed though! Maybe they just let the camera float in space with the mirror up, triggering it remotely.

You might misunderstand how ISO works on digital cameras. (I did.) https://www.youtube.com/watch?v=ZWSvHBG7X0w

Good grief, that video suffers the YouTube-ism of "ramble on about how you don't understand X" for way too long.

Video alleges people think ISO makes the sensor "more sensitive or less sensitive". (I … don't think this is common? But IDK, maybe this is my feldspar.)

(The video also quibbles that it is "ISO setting" not "ISO" … while showing shots of cameras which call it "ISO", seemingly believing that some of us believe ISO is film speed, in a digital camera?)

Anyways, the video wants you to know that it is sensor gain. And, importantly, according to the video, analog gain, not digital gain.¹ I don't know that the video does a great job of saying it, but basically, I think their argument is that you want to maximize usage of the bits once the signal is digitized. Simplistically, if the image is dark & all values are [0, 127], you're just wasting a bit.

You would want to avoid clipping the signal, so not too bright, either. Turn your zebras on. (I don't think the video ever mentions zebras, and clipping only indirectly.)

The video does say "do ISO last" which I think is a good guideline. Easier said than done while shooting, though.

… also while fact checking this comment, I stumbled across Canon's KB stating to use as low an ISO as possible, which the video rails against. They should talk to Canon, I guess?

¹with the caveat that sometimes there is digital gain too; the video notes this a bit towards the end.

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