Crescents in July 2012, observed from Muscat, Oman

Version 29.7.2012 Martin Elsaesser,

All observations were done from Muscat, Oman, during a one week visit.

Old crescent on 17. July

The easy crescent put up quite a fight, using clouds and enormous amounts of haze to hide in. I had to stalk it for more than one hour, standing on the open window of my hotel room till the crescent became visible in a gap in the clouds. By then, the crescent had reached a height of 20° und the sun was due to rise soon thereafter. In the end, it was also seen with the naked eye.

twilight with clouds
Clouds and haze during twilight covered the crescent, but venus and jupiter where visible.

old crescent in clouds
The old crescent finally becomming visible between the clouds, shortly before sunset, at -27h, 24° elongation.

old crescent in clouds, more contrast
Contrast enhanced view of the same image.

sunrise in the dust
Sunrise hidden in the dust.

Young crescent on 20. July

We started well before sunset, using a mobile telescope optimized for crescent observations. Sky conditions were very hazy, but free of visible clouds. We could quickly see the crescent with the CCD camera and the telescopes tracked it well. This crescent was not a difficult task for the crescent imaging system. Switching to the visual view, we could later also see the crescent visually through the telescope after sunset. 5 observers where present and i think we all saw the crescent visually, but it was not easy and finding precise focus for each observer was important. We could NOT see the crescent with the naked eye.
I took some images with a standard DSLR through the telescope, to get images similar to the visual view. I show a raw image from the DSLR, a contrast-stretched image from the DSLR and an image from my dedicated crescent imaging system, all taken with the same telescope.

The crescent telescope, showing the contrast-enhanced live-view of the crescent. We hardly had to touch the software for this easy occasion.

processed view of the crescent
Live image of the crescent, from the automatic crescent observation software. The view stayed the same all the way to local horizon, despite tons of haze. The automatic software compensated for most of the changes in brightness.

raw image of the crescent
Raw image of the crescent, taken with a DSLR with the same telescope.

contrast enhanced image of the crescent
Contrast enhanced image of the DSLR crescent.

scorpius and colorful skies
Later, the constellation scorpius was seen in colorful skies.

Young crescent on 21. July

We went to the future OAS area near muscat and setup the instruments before sunset. The easy crescent could be seen with naked eye before sunset. We spent two hours there and enjoyed the coming of darkness.

crescent and shadow of the instrument
The crescent in the sky before sunset, as seen over the telescope.

crescent telescope
The mobile crescent telescope and the setting sun. We did not even use the powerful camera and software on this occasion.

Early image of the crescent, taken with a DSLR through the telescope, while the sky was still blue.

Later image of the crescent through the telescope, with the earthshine showing.

View of the evening view towards the west, with crescent and lights.

evening activities
Evening activities on the first day of Ramadan.

Ein Mann bei der Betrachtung des Mondes.

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