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Comment by icc97 | Hacker News Reader

It was all super impressive until the last photo of the sunset shot over the bridge, there seems something artificial about that. Possibly the blur of the car on the far side, but it's more than that. Just not sure what.

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One problem is that if you don't live at the same longitude as where this shot is simulated, the colours are literally going to look wrong, giving you an overall feeling of "there's something off about this and I don't know what". It's the same reason why you can regret buying a beautiful jacket in Norway, only to discover it looks "completely different" when you get back to your homestead in Wisconsin.

Why would longitude affect an image like this? Can you elaborate?

They meant latitude.

As per the other comment, I meant latitude, not longitude.

but would we look at a photograph taken in another part of the world and suspect it of being computer generated?

You would if it were in an article about computer generated imagery.

That's true. I guess the context is key here!

It’s the trailer. Too much extra light on the rear surface to make it visible. Reproducing that shot with a camera would not produce such vivid clarity on that surface.

Which itself is a problem of global illumination. It's quite easy to mostly mask the lack of absolutely perfect ray tracing illumination by adding a basic ambient illumination, but it has this sort of odd effect.

The other problem is that the scene is too clean - there's no haze, or smoke which you'd expect from a highway shot.

Comparing it to three random pictures of roads at sunset:

https://pixabay.com/p-280863/?no_redirect

https://pxhere.com/en/photo/118396

https://pxhere.com/en/photo/1165757

The main difference appears to be that the pixar picture is way blurrier, the lines and detail in reality are just way more crisp. Perhaps the pixar picture is supposed to be in motion, but motion blur should be reduced over distance while even the background trees and sky are blurry.

The blacks in pixars image also don't really seem black enough for a sharp sun at sunset. You'd think at least the cabels right in front of the sun would have higher contrast. While on the other hand, some highlights don't seem to be as strong as you expect (the metal railing on the opposite side)

Overall, you kind of expect your eyes to hurt in a situation like this, but it's all very soft and gentle.

The foliage on the horizon looks like video-game flat sprites to me, with heavy blur to make up for lack of detail.

The rear of the truck is lit up in a way that is only achievable with flash, reflectors or other illumination tricks, but it is achievable.

Not just the car, the sides of the image are slightly blurred. The effect is a little similar to chromatic aberration, which tends to give an image an "artificial" feel.

It's probably a grab from the movie that has 1/24s motion blur effect. Note the car on the opposite side of the road.

I think the dynamic range is too compressed. In a real photo, you'd expect to see the difference in brightness between the clouds and the shadows be far greater.

The only part that really threw me off was the graphics on the race car hauling truck. Other than that it just looked like an over stylized picture with some sort of filter on it.

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