Though the EXIF data says this is a 15 second exposure, it is actually the combination of 80 separate 15 second exposures taken between 1:48 AM and 2:35 AM. I wanted a decent image of this scene at night at 80 ISO, but since the camera's shutter speed maxes out at 15 seconds, the only way I could think to do this was to take multiple shots and combine them. I tried combining 10 pictures in the neighboring deviation titled "150 Seconds of Night" and was decently pleased with the results. Hoping to get a sharper image, I knocked the aperture down from F/2.8 to the camera's minimum of F/8.0 and raised the number of exposures from 10 to 80 to compensate for the reduced aperture. I loaded them in groups of 10 addition-mode layers in gimp to add up the faint light I was able to collect in each image. I then did the same with the 8 resulting images. The final image had noticeable vertical bands. More specifically, it appeared that every 8th pixel-column was brighter than the rest. I'm honestly not sure what caused this. It could be that by using such a small aperture (theoretically, 0.625 mm in diameter), diffraction is affecting the image. The fact that the bright line occurs consistently every 8th pixel-column, and that I couldn't see any similar horizontal artifacts leads me to believe that it is more likely the result of either the microscopic arrangement of the elements on the CCD or the result of a propagated JPEG compression artifact, or possibly both. Heck, maybe it's all three. The camera, much to my dismay, does not offer a RAW format, but I keep it on Super-Fine which, according to gimp, is 95-quality. It's reasonable to suppose it's possible that after combining 80 images compressed the same way, some sort of propagated error would become noticeable. To remove the subtle lines, I applied an 8-pixel-wide "Destripe" filter in gimp. This did a decent job of fixing the line, but on areas of the image that were maxed out in brightness, it caused dark lines instead. I guess I could have fixed this by first finding the maxed-out areas in the original image and pasting them over top of the "fixed" image, but I didn't feel like it and it seems like photo-manipulation to me any time you modify only part of an image so I generally won't do that, unless photo-manipulation is my intent. The image also had a slightly grayish (as opposed to black) look in the dark areas, probably because of combining so much faint light bouncing around inside the camera's lens system. To help this without screwing too much with the image, I ran a "Normalize" adjustment on the image in gimp, which stretches the brightness values of an image to fill the maximum range (so the presence of a single black and single white pixel in an image is enough to cause this adjustment to have no effect).

Tell me what you think. The 150-second, F/2.8 image is here: [link]
Personally, I think it looks better than this one. I think this one is simply abusing the camera's output, trying to get too much information by combining too many, too faint images. What do you think?

Oh yeah, by the way, the light in the picture is coming from a (probably) 50-watt bulb behind an orange diffusing glass or plastic cover in the back yard of house on a road perpendicular to the road on which the house having the backyard in the foreground is located. It is shining through a thin section of forest that separates the properties.

Focus: Infinity
Combined Exposure Time: 20 minutes (1,200 seconds)
Download Resolution: 3648x2736 (10M)


Here is one of the 80 images used to make this picture: [link]