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On November 21, 2022, the Orion Navigation Camera made several images of the lunar surface.

Flight Day 6: Orion's Optical Navigation Camera Captures Lunar Surface
NASA ID: art001e000333 - 2022-11-21
Flight Day 6: Orion's Optical Navigation Camera Captures Lunar Surface

The image quality is much lower than those from the Lunar Reconnaissance Orbiter (as an example). The images have poor contrast, blown out brightness and some have white lines across them that makes them look like they were faxed.

Outside of Giordano Bruno - LRO - 2011-08-25
Outside of Giordano Bruno

Is this due to a priority for navigation over higher quality (cost, weight)? Or are they unprocessed or "previews" of slower-to-transmit, higher quality images?

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    $\begingroup$ I haven't been able to find the mass of the Orion navigation cameras, but the LRO cameras are quite hefty. Each near field camera is 8.2kg, and there's two. The wide field is about 1 kg. Plus another 1kg to pull them all together and compress the data. That's about 20% of its mass. $\endgroup$
    – Schwern
    Nov 26, 2022 at 18:35
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    $\begingroup$ I would not be at all surprised if the Orion navigation camera is intentionally overexposed. The purpose of this camera is to easily identify the outline of the Moon or the Earth, thereby aiding navigation, and an overexposed image helps in that regard. Aiding navigation is why the camera exists. Taking pretty pictures is not in the picture. $\endgroup$ Nov 28, 2022 at 18:57
  • $\begingroup$ @DavidHammen: Makes sense, but I find it curious that I've seen these pictures referred to as "gorgeous". $\endgroup$ Nov 28, 2022 at 20:24

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A navigation camera is going to have different goals than one designed to study fine details. Specifically, the navigation camera's goal will be to make recognition of key objects as reliable as possible. Most computer vision algorithms are going to pre-process the image into something that doesn't look all that pretty, but makes feature detection more reliable.

According to the video FSW 2021: Orion Optical Navigation - Lorraine Prokop, it's only goal was to match the arc on phases of the Earth and Moon in order to compute a trajectory home in the case of loss of communication. So it simply was never intended to take pretty pictures of the moon. More specifically, looking at the test images, it appears to deliberately blow out the brightest parts to make the circular shape easier to detect.

The "fax machine" lines, appear to be "dead rows" on the image sensor. From this video you'll see the lines are in the same place on all images.

Also, if you click on any of the images in your link, you'll see some text stating that these are tests of the camera's reliability.

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Probably the images are raw and not stacked yet, and NASA may need to release a large number of images of the same place after merging and combining.

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  • $\begingroup$ What do you mean by "stacking" here? You can't stack images of nearby objects unless they are taken with the exact same perspective with the exact same illumination. I doubt there was any stacking happening with the LRO images. $\endgroup$
    – asdfex
    Nov 27, 2022 at 13:41
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    $\begingroup$ Stacking does not help on overexposed images. It only helps to reduce noise on underexposed ones (to increase the signal to noise ratio). $\endgroup$ Nov 28, 2022 at 14:45

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