Chasma Boreale – Mars Reconnaissance Orbiter

Chasma Boreale - Mars Reconnaissance Orbiter

Natural color image of Chasma Boreale, a large canyon carved into the edge of Mars’ north polar ice cap. The large cliff at image center is 1.4 km (4,600 feet) high, and exposes alternating layers of ice and dust that have accumulated over tens of thousands of years. Computer models suggest that this canyon is formed by cold air flowing off the polar cap during winter, creating gusty winds that favor the removal of material. Some evidence for this can be seen in the large dune field filling the canyon floor.

This natural color was created using the CRISM imaging spectrometer. Each pixel of a CRISM image contains a 500 point spectrum, from which a color can be reconstructed. This reconstructed color was overlaid on a higher-resolution image taken with the Mars Reconnaissance Orbiter Context Camera (CTX), which simultaneously took a photo while CRISM was collecting data.

This image was taken on November 28, 2006. It uses CRISM observation HRL0000330c and CTX observation P01_001593_2635_XI_83N241W

Image Credit: NASA / JPL / JHUAPL / MSSS / Justin Cowart

Posted by jccwrt on 2020-10-24 20:00:27

Tagged: , Mars , Mars Reconnaissance Orbiter , CRISM , CTX , Chasma Boreale , ice cap , Mars North Pole , dunes

Dunes

Dunes

Another from today’s walk. Believe it or not, most of the Presidio, and a good chunk of all of western San Francisco, used to be made up of grasslands covering fields of sand dunes. The City put streets, houses, and Golden Gate Park on them, while the Army installed massive forests of Eucalyptus and other trees as a show of its power and ability, creating the landscape that still remains in the Presidio today. The Presidio Trust is currently in the process of restoring these native dunes to a small part of the park, seen here, which was formerly home to a Nike missile site.

I typically do very little processing on my photos, limiting myself to lens corrections and some adjustments to contrast, saturation, and white balance, as well as some removal of my pesky sensor dust. I don’t want to get into heavy processing in general, mostly because I enjoy the part where I’m out taking photos so much more than the time sitting in front of a computer. That said, I am trying to experiment a bit more, since it can be important to know from time to time. This shot was my overprocessing experiment for the day. I liked the shadow across the dunes, but there was just no way to get the exposure right without blowing out the sky. I opted for a bracketed exposure setting the main exposure for the dunes, and going down 2 and 4 stops for the other shots to get good detail in the sky. I used an HDR merge to combine the exposures as both a black and white set and a color set, adjusted the saturation to where I wanted it, and then overlaid the color version on top of the b&w. Finally, I made the color layer slightly transparent to get a bit of the gray to come through and give it a slightly washed out look, and merged the layers for the final image.

I certainly wouldn’t want to go through all that effort on a regular basis, especially with my terribly slow computer right now, but I had some fun with it for this shot.

Posted by mike dillon on 2011-03-13 09:17:15

Tagged: , Presidio , san Francisco , SF , sand , dunes , sun , lens flare , flare , shadow , silhouette , power lines , shuttersaltw8

Lights Last Kiss, Mesquite Dunes, Death Valley National Park

Lights Last Kiss, Mesquite Dunes, Death Valley National Park

****better on black****

Got a call from a great guy and great photographer a couple days ago about hitting up Lake Tahoe and Yosemite and it crushed me to not be able to go. I’ve been working double time at work as the year draws to an end and I had to shoot a senior and family portrait last night that just couldn’t be rescheduled.
Since I couldn’t head out to shoot, I figured I’d drop back into my spring break trip and pull out another shot. Sort of a …virtual… mental photo trip of sorts. Couple computer freezes (stupid macbook pro) later and here we have it. I hope you enjoy. I like the highlights on the dune ridges. Cheers

–jared r.

Canon 5DMKII
Canon 16-35mm @ 28mm
Iso 160
f/19
1.5 sec
Singh-Ray 2 stop SE GND
Singh-Ray 3 stop RE GND

Raw files handled in Lightroom
Final adjustments (luminosity/dust) in Photoshop CS5

www.ropelatophotography.net

Posted by Jared Ropelato on 2011-05-19 12:52:39

Tagged: , 16-35mm , 2011 , 5D MKII , 5d mark ii , Outdoor , adventure , beautiful , cable release , california , canon , clouds , crash , creek , crick , death valley , dune , dunes , eastern sierras , filter , giotto , hike , illuminate , illumination , jared ropelato , landscape , lansdscape , light , lights , long exposure , manfrotto , mesquite , mesquite dunes , national park , nature , park , rocks , ropelato photography , rugged , scene , scenic , shrubs , sierra , sierras , singh-ray , site , sky , spring , trail , travel , tree , trip , tripod , vacation , wild , wilderness