One afternoon in late December, Beverly had looked out the sunroom windows, which face in a southerly direction, and saw clouds which showed multiple colors which changed as she watched. She immediately called me and I came with my camera. The clouds involved were relatively thin and the only areas with the colors were near the sun. To photograph these clouds I had to keep the sun out of the picture frame, otherwise no colors were visible because of the brightness of the sun. As I watched, the colors changed and sometimes they disappeared and then reappeared. The phenomenon only lasted for a few minutes as the moving clouds got thicker and the color formation was no longer possible. The seven photos in the Additional Images gallery below were all taken within a minute and 43 seconds.
The formation of colors in clouds, known as irisation, is relatively rare. It is a similar to the colors seen in soap bubbles or the sheen of oil on a water surface. It is an optical phenomenon that occurs in thin clouds, only in the direction of the sun. The colors are caused by diffraction or bending of the sun’s light around the small water droplets in the cloud. This is different than mechanisms that form rainbows and sun dogs.
Additional Images
Additional Information
ThoughtCo: What Causes Rainbow-Colored Clouds in the Sky?
Cooperative Institute for Meteorological Satellite Studies: Iridescent Clouds
Technical Data
Iridescent Clouds 1
- Date: 12/26/2021
- Time: 2:22 PM
- Camera: Canon EOS 77D
- Lens: Canon EF-S 55-250 mm f/4-5.6 IS STM
- Settings:
- Lens: 84 mm, f/25
- ISO: 100
- Shutter: 1/400 sec
- Uncropped image is 6000 x 4000 px
Iridescent Clouds 3
- Date: 12/26/2021
- Time: 2:22 PM
- Camera: Canon EOS 77D
- Lens: Canon EF-S 55-250 mm f/4-5.6 IS STM
- Settings:
- Lens: 70 mm, f/20
- ISO: 100
- Shutter: 1/400 sec
- Uncropped image is 6000 x 4000 px
Iridescent Clouds 5
- Date: 12/26/2021
- Time: 2:21 PM
- Camera: Canon EOS 77D
- Lens: Canon EF-S 55-250 mm f/4-5.6 IS STM
- Settings:
- Lens: 61 mm, f/22
- ISO: 100
- Shutter: 1/400 sec
- Uncropped image is 6000 x 4000 px
Iridescent Clouds 7
- Date: 12/26/2021
- Time: 2:22 PM
- Camera: Canon EOS 77D
- Lens: Canon EF-S 55-250 mm f/4-5.6 IS STM
- Settings:
- Lens: 64 mm, f/20
- ISO: 100
- Shutter: 1/400 sec
- Uncropped image is 6000 x 4000 px
Iridescent Clouds 2
- Date: 12/26/2021
- Time: 2:21 PM
- Camera: Canon EOS 77D
- Lens: Canon EF-S 55-250 mm f/4-5.6 IS STM
- Settings:
- Lens: 84 mm, f/22
- ISO: 100
- Shutter: 1/400 sec
- Uncropped image is 6000 x 4000 px
Iridescent Clouds 4
- Date: 12/26/2021
- Time: 2:21 PM
- Camera: Canon EOS 77D
- Lens: Canon EF-S 55-250 mm f/4-5.6 IS STM
- Settings:
- Lens: 55 mm, f/20
- ISO: 100
- Shutter: 1/400 sec
- Uncropped image is 6000 x 4000 px
Iridescent Clouds 6
- Date: 12/26/2021
- Time: 2:22 PM
- Camera: Canon EOS 77D
- Lens: Canon EF-S 55-250 mm f/4-5.6 IS STM
- Settings:
- Lens: 64 mm, f/22
- ISO: 100
- Shutter: 1/400 sec
- Uncropped image is 6000 x 4000 px