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ISS Solar Transit
I guess it's also the right setting for pictures of the Moon at night.
Title text: I guess it's also the right setting for pictures of the Moon at night.

Explanation

Ambox notice.png This explanation may be incomplete or incorrect: More on the title text. Would the direct sunlight not be a bad choice for taking pictures of the moon, although the full Moons surface is in more direct sunlight thatn anything down on Earth (due to the atmosphere). What is DSLR camera. Is this a similar camera like the Superzoom comic?

Cueball is trying to take a photograph of the International Space Station moving in front of the sun (example). He has his camera with a long lens set up with a fixed setting to keep it still while he contemplates the best way to get the photographs he wants.

A normal camera is not able to take a photograph of the sun due to the extreme brightness. This is why Cueball is using a solar filter, which makes the sun look orange instead of white as shown in the second panel.

Digital cameras need to determine the color temperature of a photograph to correctly display colors. This is done using the white balance setting. The joke here is that Cueball selects the "direct sunlight" option, as he feels it is the option that best suits his unusual situation of directly photographing the sun, even though the "direct sunlight" setting is intended to be used for photographing objects directly illuminated by the sun and not for the sun itself.

The light from an object illuminated by "direct sunlight" is, in fact, indirect sunlight when it reaches the camera sensor; so when photographing the sun itself, the camera receives sunlight that is even more direct than "direct".

The use of a solar filter influences the color temperature, so "custom" would probably be the correct option here. A camera using the "custom" option usually requires you to focus on a white or gray object first to determine the correct setting. Most high-end cameras, like the superzoom camera that is likely depicted here, are able to capture in raw image format, allowing the user to adjust the white balance afterwards in software.

The title text is pointing out that the sunlit side of the moon is also in direct sunlight, which is why we are able to see it, and so "direct sunlight" would actually be the correct setting in this case.

It is the second comic within a week where Cueball is using a camera, similar to the one he used in 1719: Superzoom. The previous comic was 1826: Birdwatching two comics before this one.

Transcript

[Cueball is kneeling in front of a small platform while operating a camera with a very long objective. The camera is angled sharply upward toward the sky as it is attached to a tripod standing on the platform. An off-panel voice calls ut to him.]
Off-panel voice: What's going on?
Cueball: ISS solar transit. From this spot, the space station should briefly line up with the sun.
Cueball: I got a sun filter and I'm trying to take a picture of it crossing.
[Two half height panels above each others follow. The first shows an image of the very orange sun on a black background, as seen through the camera.]
[The second of the two half height panels shows Cueball making further adjustments tot he camera, as in the first panel.]
Cueball: Perfect. Hmm, I should set the white balance.
[Once gain there are two panels above each other. The top is black with white text and icons from the white balance menu. It has the following options shown after each of the icons as mentioned below in the square brackets:]
[Shining light bulb]: Incandescent
[Shining fluorescent lamp]: Fluorescent
[Shining sun]: Direct sunlight
[Lightning]: Flash
[Cloud]: Cloudy
[A house that cast a shade]: Shade
[Two triangles with a circle between them]: Custom
[In the panel below Cueball still operates the camera as before]
[A frame-less but full height panel follows where Cueball leans back from the camera with his hands on his thighs.]
[The last two panels are again above each other. It is almost the same panels as before the frame-less panels, except that the direct sunlight option has been selected as shown with a blue selection band across that option.]
Incandescent
Fluorescent
Direct sunlight
Flash
Cloudy
Shade
Custom
[In the bottom panel Cueball again operates the camera.]


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