APOD: Celestial Trails over Greece (2011 May 04)

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Expand view Topic review: APOD: Celestial Trails over Greece (2011 May 04)

Re: APOD: Celestial Trails over Greece (2011 May 04)

by neufer » Wed May 04, 2011 11:07 pm

YHaalhouse wrote:
What dreadful out of time amateur music though!
  • [list]Shakespeare's "Lucrece"; stanza 141:
'Let him have time to tear his curled hair,
Let him have time against himself to rave,
Let him have time of Time's help to despair,
Let him have time to live a loathed slave,
Let him have time a beggar's orts to crave,
And time to see one that by alms doth live
Disdain to him disdained scraps to give.

'Let him have time to see his friends his foes,
And merry fools to mock at him resort;
Let him have time to mark how slow time goes
In time of sorrow, and how swift and short
His time of folly and his time of sport;
And EVER let his unrecalling crime
Have time to wail th' abusing of his time
[/b][/size].[/list]

Re: APOD: Celestial Trails over Greece (2011 May 04)

by badsocref » Wed May 04, 2011 10:40 pm

It's very beautiful, and I sort of like the music. I did a similar fading star trails image (not movie) when Comet Hartley 2 visited us last Fall. Yeah, it ain't the way stars really trail, but I thought it was a unique presentation style. Glad to see somebody get it published on APOD.

Re: APOD: Celestial Trails over Greece (2011 May 04)

by YHaalhouse » Wed May 04, 2011 7:10 pm

What dreadful out of time amateur music though!

Re: APOD: Celestial Trails over Greece (2011 May 04)

by owlice » Wed May 04, 2011 5:54 pm

Rose wrote:Yeah, this is the weird photo I got as well........how can I avoid these type APOD's? They make me nauseas!
For information on this issue, please see this thread. Thanks.

Re: APOD: Celestial Trails over Greece (2011 May 04)

by neufer » Wed May 04, 2011 5:52 pm

geckzilla wrote:
Close up of The Tree! :tree: Most APODded tree ever. :)
http://en.wikipedia.org/wiki/Apodization wrote:
<<APODization literally means "removing the foot". It is the technical term for changing the shape of a mathematical function, an electrical signal, an optical transmission or a mechanical structure. An example of apodization is the use of the Hann window in the Fast Fourier transform analyzer to smooth the discontinuities at the beginning and end of the sampled time record.

In optical design jargon, an apodization function is used to purposely change the input intensity profile of an optical system, and may be a complicated function to tailor the system to certain properties. Usually it refers to a non-uniform illumination or transmission profile that approaches zero at the edges. The diaphragm of a photo camera is not strictly an example of apodization, since the stop doesn't produce a smooth transition to zero intensity, nor does it provide shaping of the intensity profile (beyond the obvious all-or-nothing, "top hat" transmission of its aperture). Simulation of a gaussian laser beam input profile is an example of apodization.

Apodization is used in telescope optics in order to improve the dynamic range of the image. For example, stars with low intensity in the close vicinity of very bright stars can be made visible using this technique, and even images of planets can be obtained when otherwise obscured by the bright atmosphere of the star they orbit. Generally, apodization reduces the resolution of an optical image; however, because it reduces diffraction edge effects, it can actually enhance certain small details. In fact the notion of resolution, as it is commonly defined with the Rayleigh criterion, is in this case partially irrelevant. One has to understand that the image formed in the focal plane of a lens (or a mirror) is modelized through the Fresnel diffraction formalism. The classical diffraction pattern, the Airy disk, is connected to a circular pupil, without any obstruction and with a uniform transmission. Any change in the shape of the pupil (for example a square instead of a circle) or in its transmission results in a change of the diffraction pattern.>>

Re: APOD: Celestial Trails over Greece (2011 May 04)

by Rose » Wed May 04, 2011 5:46 pm

Yeah, this is the weird photo I got as well........how can I avoid these type APOD's? They make me nauseas!

Re: APOD: Celestial Trails over Greece (2011 May 04)

by prizzel » Wed May 04, 2011 5:28 pm

I get a bit annoyed when my APOD Screensaver gives me some silly photo of something non-celestial........today's "Pic" was actually a video...is this the reason I get this stuff?

Re: APOD: Celestial Trails over Greece (2011 May 04)

by geckzilla » Wed May 04, 2011 5:22 pm

agulesin wrote:PS Can anyone tell me what the link to "unfamiliar fashion http://www.baraskit.se/random/img/89/st ... hion/1.jpg" reveals? for some reason I couldn't get into it...
It's this weird picture:
Image

Re: APOD: Celestial Trails over Greece (2011 May 04)

by Ailean4321 » Wed May 04, 2011 4:05 pm

ChrisKotsiopoulos wrote:Have a look at the ship wreck startrails. You can actually see the tide at the little pool in front of the ship and the progressing startrail reflections.
I noticed that. There is something about an old ship that captures my soul for some reason. Add that to stars and I'm completely enthralled. I think you did an awesome job! Thank you for your time and effort. :mrgreen:

Re: APOD: Celestial Trails over Greece (2011 May 04)

by Ailean4321 » Wed May 04, 2011 4:03 pm

geckzilla wrote:Powers of Ten
much thanks!! :D

Re: APOD: Celestial Trails over Greece (2011 May 04)

by ChrisKotsiopoulos » Wed May 04, 2011 3:36 pm

Thank you all for your kind words! This is the best possible result of more than two years of effort.
:mrgreen:

Alnilam I'm sorry you didn't like it. As my friend Anthony said it is a matter of process.
Have a look at the ship wreck startrails. You can actually see the tide at the little pool in front of the ship and the progressing startrail reflections.
See also this video and observe the Moon's shadow and the flowers move. Same video, different process:
http://vimeo.com/10158550

Re: APOD: Celestial Trails over Greece (2011 May 04)

by terryantrim » Wed May 04, 2011 2:56 pm

the best ever-4= yrs of viewing

Re: APOD: Celestial Trails over Greece (2011 May 04)

by agulesin » Wed May 04, 2011 2:23 pm

snowwolf wrote:Almost perfect ... but the second sentence of the description says "star trials" instead of "star trails" ... ahh those typos!
They were testing the stars, auditioning them before they take part in another blockbuster to be released soon!

I couldn't watch it to the end, I think a little on the long side. and the music? well, that goes without saying... :roll:

PS Can anyone tell me what the link to "unfamiliar fashion http://www.baraskit.se/random/img/89/st ... hion/1.jpg" reveals? for some reason I couldn't get into it...

Re: APOD: Celestial Trails over Greece (2011 May 04)

by geckzilla » Wed May 04, 2011 2:20 pm

Ailean4321 wrote: Does anyone know the date of the video that expands through the universe and then zooms back in to quantum level? I remember seeing it a while back and would like to watch it again.
Powers of Ten

Re: APOD: Celestial Trails over Greece (2011 May 04)

by geckzilla » Wed May 04, 2011 2:18 pm

I guess vimeo's mute button isn't so obvious to everyone. It's the little blue vertical bars directly to the right of the play header bar. If you click to the left of those bars, it mutes the music. Anyway...

Close up of The Tree! :tree: Most APODded tree ever. :)

Re: APOD: Celestial Trails over Greece (2011 May 04)

by goodtime » Wed May 04, 2011 1:54 pm

Would have loved to watch the whole thing but the background music was so bad I had to turn it off.

Re: APOD: Celestial Trails over Greece (2011 May 04)

by Dustin » Wed May 04, 2011 1:52 pm

Nice. Very soothing start to my morning Thanks.
I like the way the star trails look like a slow motion meteor storm.

Re: APOD: Celestial Trails over Greece (2011 May 04)

by Ailean4321 » Wed May 04, 2011 1:27 pm

Absolutely loved this!!
I really enjoy when the APODs are videos. Its a nice change, although I love the photos as well.
Does anyone know the date of the video that expands through the universe and then zooms back in to quantum level? I remember seeing it a while back and would like to watch it again.
Thanks!
I hope everyone has a wonderful day! :)

Re: APOD: Celestial Trails over Greece (2011 May 04)

by moonstruck » Wed May 04, 2011 12:54 pm

Fantastic very well done Chris.

Re: APOD: Celestial Trails over Greece (2011 May 04)

by Lang » Wed May 04, 2011 12:53 pm

Why was it necessary to underpin those pictures with blaring, banal pop music? I can't think of anything more at odds with the pictures than that.

Re: APOD: Celestial Trails over Greece (2011 May 04)

by snowwolf » Wed May 04, 2011 12:25 pm

Almost perfect ... but the second sentence of the description says "star trials" instead of "star trails" ... ahh those typos!

Re: APOD: Celestial Trails over Greece (2011 May 04)

by orin stepanek » Wed May 04, 2011 11:54 am

Well done; and very nice! 8-)

Re: APOD: Celestial Trails over Greece (2011 May 04)

by Ayiomamitis » Wed May 04, 2011 11:33 am

Indigo_Sunrise wrote: I especially liked the series where the stars appear to be rotating backwards - I'm assuming this is because the camera is pointing at the south celestial pole....?
When the camera is pointing west, thus catching the stars setting, we have a view similar to that involving the Temple of Poseidon at Sounion (in Chris' video) which does indeed seem like the stars are rotating backwards. We are so used to watching stars rise that anything else if almost abnormal. :-)

Anthony.

Re: APOD: Celestial Trails over Greece (2011 May 04)

by Indigo_Sunrise » Wed May 04, 2011 10:52 am

I thought this video was very well done! And owlice, I agree: the 'raining stars' were pretty awesome!

And thank you, Ayiomamitis, for explaining some of the process on how this was done. (I was getting ready to repost what is fast becoming (in my mind) the APOD mantra: "If you don't like it, come back tomorrow." Or don't; we surely won't miss you!)

I especially liked the series where the stars appear to be rotating backwards - I'm assuming this is because the camera is pointing at the south celestial pole....?

Oh, and does anyone have a 'roundabout' way to view the images that are at the 'greeksky.gr' site? My work is denying access...... :cry:

A very beautiful video!

8-)

Re: APOD: Celestial Trails over Greece (2011 May 04)

by Ayiomamitis » Wed May 04, 2011 9:43 am

Alnilam wrote:More of "time-lapses" in this video are not very natural : it is obvious that the changing sky is added on a still image of landscape,
For anyone who has physically done this kind of work, the "obvious" is NOT so obvious. If we keep the camera fixed, thus having a constant field of view during the sequence, you will get what Chris has produced. The animation is created by layering sequential still images and where the brightest pixel is now added, thus incorporating the latest still and which yields motion.
otherwise trees or flowers must be shaked by the wind.
Your underlying premise is flawed. If there is NO wind, there would be no shaking of trees or flowers.
It is very different in the last sequence with the flag.
The only thing different involving Lycabettus Hill and the waving flag is the presence of winds themselves on that particular afternoon.
I suppose that this choice was made to avoid the blinking of landscape, very frequent in "time-lapse" because of changes in light (clouds).
This is software-dependent and how we handle the transition from frame to frame in the animation.
Another reason to do so : star trails are made with a dark sky and the landscape is generally almost black and appears in a "shadow" mode. Without any artificial light, landscape is lightened by the moon sooner or later in the night...
I think you missed the point here. One needs lighting (ex. the young moon) so as to illuminate the foreground. Otherwise, under a dark sky, the foreground will be grossly underexposed (if at all visible). One can result to artificial means to lighting the foreground (such as a powerful flash) but the natural lighting provided by the moon is, in my opinion, the best means.
In any case, the result is very artificial.
This is unfortunate since such a result involves a serious amount of work!

Great job, Chris.

Anthony.

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