Comments and questions about the APOD
on the main view screen.
- Otto Posterman
- Posts: 5144
- Joined: Fri Dec 04, 2009 3:27 am
On the Road to Carina
This rugged road through the dark Atacama Desert seems to lead skyward
toward the bright stars and glowing nebulae of the southern Milky Way. If you follow the road you will get to Cerro Armazones peak in Chile
, future construction site for the 40-meter class European Extremely Large Telescope
. For now though, sliding your cursor across the image will identify wonders of the southern skies
in view. The scene is dominated by the reddish glow of the Great Carina Nebula
, one of our galaxy's largest star forming regions. In fact, the remarkable skyscape
is not a composite of varying exposures or a photomontage. Far from sources
of light pollution, the landscape illuminated by starlight and the Milky Way above were recorded by a modified digital camera and fast lens. The sensitive system captured both planet Earth and deep sky in a relatively short exposure
- 4725 Å
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- Joined: Sat May 29, 2010 5:33 am
For a northerner, the constellations are "upside-down", so it took me a while to recognize them.
But what an image! The road is illuminated by the Milky Way, and we see all these nebulae and clusters and their colors in a relatively short exposure! Amazing!
I would like to hear more about the modified digital camera. What was the original camera? What mods (physical/electronic/software) were performed? What sensor inside? ISO rating? RAW or some special image format? Post processing? Is there a description link available?
The beauty of the image is not lost on me, but I want to know more of "how they did it". Unless It's magic, I want to know how it was done. Fill in some of the gap between the awe and the arcane. Maybe I could do it too, or appreciate it at another level. Get me started, I'll do the rest.
- Guardian of the Codes
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- Location: Washington, DC
bub4280 wrote:I would like to hear more about the modified digital camera.
I followed links, and found this page
which might be of help to you.
A closed mouth gathers no foot.
- Abominable Snowman
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- Location: Guffey, Colorado, USA
bub4280 wrote:I would like to hear more about the modified digital camera. What was the original camera? What mods (physical/electronic/software) were performed? What sensor inside? ISO rating? RAW or some special image format? Post processing? Is there a description link available?
All DSLR cameras are noisy, but the least so is the Canon 5D (series), which also has other features that generally make it the best DSLR for astroimaging. I'd guess that's what was used. However, all Canon DSLRs have a cutoff filter in front of the sensor that blocks deep red, which includes the important hydrogen alpha line. It is possible to remove this filter, but that results in two problems: IR is not blocked, which leaks through the green and blue filters, totally messing up the color, and the IR introduces chromatic aberration issues with most camera lenses. So the usual DSLR modification used by astroimagers is to replace the long wavelength blocking filter with one that pushes the block out to IR, but passes the deep red of hydrogen alpha.
Last edited by Chris Peterson on Sat Feb 18, 2012 4:42 pm, edited 1 time in total.
Danke. Good starting point.
"There's a country spread out in the sky"
I saw it when a child.
Time to stop... And see it again.
Chris Peterson wrote:
All DSLR cameras are noisy, but...
Thanks, this addresses many of the issues on my mind.
- Vacationer at Tralfamadore
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- Joined: Mon Jan 21, 2008 1:57 pm
- Location: Alexandria, Virginia
Carina: 1. A keel-shaped constellation in the southern hemisphere; contains the start Canopus.
2. Any of various keel-shaped structures or ridges such as that on
the breastbone of a bird or that formed by the fused petals of a pea blossom.
carina : keel (Latin)
carina : customs duty (Serbo-Croatian)
cariña : sweetie, honey (Spanish)
Cariña, ya estoy en casa. = Honey, I'm home.
O carina : That's nice (Italian)
[Finnegans Wake 7.3] And all the livvylong night,
the delldale dalppling night, the night of bluerybells,
her flittaflute in tricky trochees (O carina! O carina!)
is an ancient flute-like wind instrument typified by an oval-shaped enclosed space with four to twelve finger holes and a mouth tube projecting out from the body. The word ocarina
is derived from Bolognese (Italian) dialect meaning "little goose.
is a very old family of instruments, believed to date back some 12,000 years. Ocarina
-type instruments have been of particular importance in Chinese and Mesoamerican cultures. For the Chinese, the instrument played an important role in their long history of song and dance. Different expeditions to Mesoamerica, including the one conducted by Cortés, resulted in the introduction of the ocarina
to the courts of Europe. Both the Mayans and Aztecs had produced versions of the ocarina
, but it was the Aztecs who brought the song and dance that accompanied the ocarina
to Europe. The ocarina
went on to become popular in European communities as a toy instrument. After featuring in the Nintendo Legend of Zelda games, the ocarina
attracted a marked increase in interest, and a dramatic rise in sales.>>
<<A wishing well is a term from European folklore to describe wells where it was thought that any spoken wish would be granted. The idea that a wish would be granted came from the idea that water housed deities or had been placed there as a gift from the gods, since water was a source of life and often a scarce commodity. Water was seen to have healing powers and therefore wells became popular with many people drinking, bathing or just simply wishing over it. People believe that the guardians or dwellers of the well would grant them their wish if they paid a price. After uttering the wish, one would generally drop coins in the well. That wish would then be granted by the guardian or dweller, based upon how the coin would land at the bottom of the well. Traditionally coins were made of copper or silver and had biocidal properties which kept the water from going sour (bacteria produces various acidic compounds which affect the taste, notably Hydrogen sulfide). It was thus lucky to throw coins in the well. The tradition of dropping pennies in ponds and fountains stems from this.
The Germanic and Celtic peoples considered springs and wells sacred places. Sometimes the places were marked with wooden statues possibly of the god associated with the pool. Germanic peoples were known to throw the armour and weapons of defeated enemies into bogs and other pools of water as offerings to their gods. This may be a left over from ancient mythology such as Mímir's Well from Nordic myths, also known as the ¨Well of Wisdom¨, a Well that could grant you infinite wisdom provided you sacrificed something you held dear. Odin was asked to sacrifice his right eye which he threw into the well to receive not only the wisdom of seeing the future but the understanding of why things must be. Mímir is the Nordic god of wisdom, and his well sits at the roots of Yggdrasil, the World Tree which draws its water from the well.>>
Last edited by neufer on Sat Feb 18, 2012 10:07 pm, edited 1 time in total.
- Science Officer
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- Location: Md
Forget the box, just get outside.
- 4725 Å
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Thanks for your post, Art.
I have a friend called Carina!
- Posts: 8134
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- Location: Nebraska
nice picture Babak Tafreshi; i really like it.
Smile today; tomorrow's another day!
- Science Officer
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- Location: Possum Hollow, NW Florida
Oh my ~~ how I'd love to visit here .....
- 500 Gigaderps
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biddie67 wrote:Oh my ~~ how I'd love to visit here .....
Uh, aren't you 'here', now
To find the Truth, you must go Beyond.
I want to be in my chair, having an ice cold one, when Eta carinae goes kablooye ( in Brazil partying like a brazilian )