The images were taken at indoor dark room (Temperature : 20C~22C) and the exposure time was 450sec ( 7.5 minutes).We croped 224×224 pixels in center area of original images and not resized.

In order to distinguish the deferance of each shots more easily we stretched the tone levels in Photoshop program. The default value of highlight Levels is 255 and we stretched this to  30Levels.

1.Original Images ( ISO1600, 450sec, RAW file center croped)

2.Levels stretched 255 to 30 in Photoshop ( ISO1600, 450sec, RAW file center croped)