Celestia Forums

Hi, I?€™m new about celestia. I?€™ve installed some add-on of galaxies on the directory extras, but when I open celestia, and I find the galaxies (for example M31) there is two M31, the new that I?€™ve installed and the default one. (see picture). It?€™s true? Or there is a way to delete the default celestia galaxies?

Welcome!

You know what? one of those M31 is not at the right place and don't have the right size...

Can you guess which one?

How about first learning how to correctly display Celestia's galaxies before trying to replace them with inaccurate add-ons that look like "raw oysters" but NOT like galaxies

Here is how M31 should look like:


What's so bad about it?? It's certainly much better than the crippled add-on you were using at the wrong place...

Please realize that in Celestia we read out NOT one galaxy but more than 10000 directly from the best, published scientific catalogs and render them without any human interference! Nevertheless, they are MOST accurately displayed.

Bye Fridger

But I not try to replace them with inaccurate add-ons ..... I've only take from http://www.celestiamotherlode.net the M31 add-on (the Jestr's one) and put it in the extra directory, nothing other....

tex wrote:But I not try to replace them with inaccurate add-ons ..... I've only take from http://www.celestiamotherlode.net the M31 add-on (the Jestr's one) and put it in the extra directory, nothing other....

But the most accurate distance and other galaxy data you find in the official distribution. You should of course use 1.5.0 pre3

Bye Fridger

tex,

most "realistic" addons at the Motherlode (ML) are old, and thus outdated.

You can't trust any of the addons located on the ML, especially since most of them are made by amateurs or fans of Celestia, and since *ANYONE* can publish his/her personal addon there without any professional reviews.

t00fri wrote:

tex wrote:But I not try to replace them with inaccurate add-ons ..... I've only take from http://www.celestiamotherlode.net the M31 add-on (the Jestr's one) and put it in the extra directory, nothing other....

But the most accurate distance and other galaxy data you find in the official distribution. You should of course use 1.5.0 pre3

Bye Fridger

Sorry for my ignorance about Celestia, (I've try it for the first time this week) on the official web of celestia (http://www.celestiaproject.net/celestia/) the latest version is 1.4, where can I find the 1.5?

Thanks Cham for the clarification so, add-on on http://www.celestiamotherlode.net are not accurate?!...I thought were official or however precise ... there is anoter place where is possible find add-on not outdated?

tex wrote:You mean that the add-on on http://www.celestiamotherlode.net are not accurate?

Some of them are accurate, some aren't anymore (too old), and some are pure crap ! So no addon there can be trusted. Use them as Celestia "toys" only.

Cham wrote:

tex wrote:You mean that the add-on on http://www.celestiamotherlode.net are not accurate?

Some of them are accurate, some aren't anymore (too old), and some are pure crap ! So no addon there can be trusted. Use them as Celestia "toys" only.

thanks, sin... because it is beautiful to see the galaxies with their real image.... where I can find the version 1.5?? on the official site there is only the 1.4...

Sorry, version 1.5 "official" isn't out yet. To use a "test" version, you need to do a search on the forum.

In case you are using Windows, here is the latest (after download, just click on it to install):

http://www.celestiaproject.net/~claurel/celest ... .0pre3.exe

You should know that Celestia is altogether a highly accurate space simulation, unifying spectacular 3D graphics with scientific level astronomical/astrophysical accuracy. That's why, we put great emphasis on the official distribution that has been prepared with a lot of professional know how.

But of course, you are free to install whatever you like best...However, any problems with bad add-ons, please discuss directly with their creators.

Bye Fridger

Just asking...

Has anybody (other then the addon creators) tried to make some modifications to the addons in the Motherlode? Maybe organize them? (make multiple single objects out of addon packs)
I know about the authors rights but if they dont care about them anymore
why shuld the addons lay there outdated or incomplete?

Maybe the administrator should make some rules like:
All addons need dsc, ssc or stc declatations or if the addons are outdated then somebody other then the creator can make an update (ex: people here in the forum)
Instead of arguing about what modifications should be done with the program other people like myself can provide a xyz file or a specular texture a spacecraft for example.

As for the fictional addons i don't even care if they are outdated, i never used them.

"raw oysters"

Sorry.

thanks to all for have helped me an thanks to Fridger for the link of 5.1

ElChristou

Thanks for the tip!!

You know what? one of those M31 is not at the right place and don't have the right size...

There is something else that is wrong with that picture of M31 and that is someone took artistic liscense and made it an almost face-on galaxy. Looking through a telescope M31 is at least three time longer than it is wide.

t00fri

Here is how M31 should look like:

That picture you show is someones interpetation of how M31 might look and it does not show the warping of it's spiral structure, the dual core or the galaxy's halo of stars. Once again someone is taking artistic license and showing us how they think it would look.

The beauty and complexity of not just M31 but I will also add M51 are being completely left out. The M51 (NGC5194) I see in v1.4.1.0 is completely disconnected from NGC5195 which is not correct.

NGC5195 is on a collision course with M51 and is being tidally torn apart by M51 and yet there is indication of this in Celestia. They show up as two separate items which is completely wrong.

I would suggest adding one more alternative view for all objects and that would be an actual astrophotograph of each item so people can see the beauty and complexity of the deep sky objects.

Here is one of my favorite links for astrophotos:
http://www.robgendlerastropics.com/ he has been a favorite of mine since about the year 2000 and his photos of M31 and M51 are superb.

Ok, that is my two cents worth. I am going back to enjoying "jll" addons especially the two excellent ones M2-9 series and He 2-104 both of which are impressive simulations.


Kel
*****

Kelteel wrote:t00fri

Here is how M31 should look like:

That picture you show is someones interpetation of how M31 might look and it does not show the warping of it's spiral structure, the dual core or the galaxy's halo of stars. Once again someone is taking artistic license and showing us how they think it would look.

The beauty and complexity of not just M31 but I will also add M51 are being completely left out. The M51 (NGC5194) I see in v1.4.1.0 is completely disconnected from NGC5195 which is not correct.

NGC5195 is on a collision course with M51 and is being tidally torn apart by M51 and yet there is indication of this in Celestia. They show up as two separate items which is completely wrong.

I would suggest adding one more alternative view for all objects and that would be an actual astrophotograph of each item so people can see the beauty and complexity of the deep sky objects.

You have unfortunately misunderstood completely the non-trivial underlying rendering strategy of galaxies in Celestia.

The formost task is mass rendering of 10000+ galaxies without any human intereference! Whatever you suggested above, how could this possibly be achieved for 10000 galaxies!?

The computer renders the 10000 galaxies precisely by the available information from the best published scientific galaxy catalogs. The images cannot be better than what the catalogs have tabulated about them. The idea is exactly to use absolutely NO artistic license! The used catalog data are the best available and include:

-- Hubble class (realized via generic sprite templates)
-- distance, RA, DEC, position angle rel. to north and inclination
-- length of minor and major axes
-- color profile
-- 3d morphological information of ellipticals versus spirals from corresponding scientific studies.

So you must understand this task as a /scientifically/ accurate visualization of the best available NGC/IC galaxy database and NOT as a photorealistic imaging project! If you don't like it, you are welcome to make a better proposal that can deal with 10000+ galaxies at a time and that is FAST.

Anyway your proposal of adding photographic images is completely out of the question for so many galaxies. I would certainly have done that if it was a realistic option.

You should also always upgrade to the latest beta versions of Celestia, since this is an ongoing project. Celestia 1.4.1 has been released already 1 3/4 years ago (Feb 2006)!

The distance issue with M51 - NGC 5195 that you mentioned is of course LONG eliminated! Meanwhile, I have merged the distance determination methods of as many as 10 scientific catalogs , whence all distances are as good as they can be.

If you want to include photographic images or special templates for particular galaxies, you can always do that of course, e.g. via add-ons or the "custom template" option.

Bye Fridger

Cham wrote: So no addon there can be trusted. Use them as Celestia "toys" only.

I wouldn't exactly say that no addon - whatsoever - at the Motherlode can be trusted. Some of them, especially Don Edwards' texture sets, are unbelievably astounding in terms of accuracy.

I'd even say that some nebulae are unbelievably well done. There's a 3D rendition of the Ring Nebula I downloaded from the Motherlode and was very impressed with how accurate it seemed to depict the real thing, especially how the developer placed a white dwarf inside the 3D object. (Now if only one can do the same thing in developing a 3D rendition of the most fantastic of all nebulae: The Great Orion Nebula)

I also believe that the 3D renditions of Eta Carinae (and the associated Homunculus Nebula) and the 3D rendition of the Ant and Eskimo Nebulae are stunning when comparing them to photos of the actual thing.

That's just my $.02

srosenow_98 wrote:

Cham wrote: So no addon there can be trusted. Use them as Celestia "toys" only.

I wouldn't exactly say that no addon - whatsoever - at the Motherlode can be trusted. Some of them, especially Don Edwards' texture sets, are unbelievably astounding in terms of accuracy.

I'd even say that some nebulae are unbelievably well done. There's a 3D rendition of the Ring Nebula I downloaded from the Motherlode and was very impressed with how accurate it seemed to depict the real thing, especially how the developer placed a white dwarf inside the 3D object. (Now if only one can do the same thing in developing a 3D rendition of the most fantastic of all nebulae: The Great Orion Nebula)

I also believe that the 3D renditions of Eta Carinae (and the associated Homunculus Nebula) and the 3D rendition of the Ant and Eskimo Nebulae are stunning when comparing them to photos of the actual thing.

That's just my $.02

Sorry but you are largely missing the point. /Scientific/ visualization standards that we uniformly adhere to in Celestia development is based on a /consistent/ approach, using scientific data AND their concise documentation!

As to the add-ons available on ML, many different users are involved, applying completely different visualization standards without any peer reviewing or documentation of the data sources .

Therefore, what you download is intrinsically unreliable in quality and scientific standards. You may be lucky, but mostly the result is disappointing. With all respect for the graphical beauty and the high level of workmanship of Don.Edwards' textures, Don never claimed scientific rigor of his work.

While many users might well value imaging beauty higher than consistent and precise visualization, the latter is what we have decided to follow throughout for the official Celestia development.

Bye Fridger

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