Celestia Forums

Hi all!

I'm creating a real-time 3D model of the planet Venus; using Multigen Creator. (http://www.multigen.com)

To get an idea, here's a screenshot:
http://home.hccnet.nl/lp.sussenbach/venus.jpg

The elevation is a litte exaggerated as you can see. This is using a 4k texture. But the purpose is to "fly" over the surface and therefore a higher resolution texture is required. More like 16k or even higher....

I've pretty much searched everywhere, also on this forum. But I could not find what I was looking for. Maybe you guys can help? Thanks!

You can get maps with arbitrarily high resolution from the USGS Map-a-Planet web site.

http://pdsmaps.wr.usgs.gov/maps.html

Thanks selden for the quick response! Although very, very usable, I was interested in one which is already colored and has the areas fixed where the magellan didn't scan.

I came across this page:

http://jeam.tag.free.fr/CELESTIAhtml/Ce ... tures2.htm

It mentions a 16k PNG file. The quality of the textures shown in the pictures below is what I'm pretty much talking about. It refers to 'Johns Celestia Pages' but the link is dead.

John is in the middle of revamping his home system. Supposedly it'll be up in a couple of days. Note, however, that it often is unreachable for various reasons.

Hrm,

Looking through my extras folder, I did manage to DL what appears to be a 16k PNG VT of Venus. Unfortunately I'm not sure from where, though I would guess the motherlode. It's definately not on the main site, but you might want to look for it in the "creators" directories...

http://www.celestiamotherlode.net/creators/?M=D

I've also put together a map available on my website at http://laps.fsl.noaa.gov/albers/sos/sos.html#VENUS

scalbers wrote:I've also put together a map available on my website at http://laps.fsl.noaa.gov/albers/sos/sos.html#VENUS

Steve,
was this on purpose that you did not remove the many ugly artefacts in that map. It just takes a bit of time, but it's a straightforward "homework"...

Bye Fridger

Hi Fridger,

I guess this is all relative as I did remove or reduce quite a few artofacts in the way I combined some of the individual mosaics. Perhaps I didn't look fully at all the links above as I wonder if you might show me a cleaner version existing anywhere that is 4K or higher? Anyone is welcome to post-process my map as well to clean it up a bit. I've had good reviews of this map when showing it to some planetary science folks with our "Science on a Sphere". Perhaps I'll get some time to do some more "homework" though I would also place some importance to increasing the resolution to something like 8K.

scalbers wrote:Hi Fridger,

I guess this is all relative as I did remove or reduce quite a few artofacts in the way I combined some of the individual mosaics. Perhaps I didn't look fully at all the links above as I wonder if you might show me a cleaner version existing anywhere that is 4K or higher? Anyone is welcome to post-process my map as well to clean it up a bit. I've had good reviews of this map when showing it to some planetary science folks with our "Science on a Sphere". Perhaps I'll get some time to do some more "homework" though I would also place some importance to increasing the resolution to something like 8K.

Steve,

I guess it's all a matter of one's personal standards. If such textures are to be used for Celestia type software, such artefacts are far from optimal , notably since it's routine work to eliminate them completely ==>



Cheers,
Fridger

Kolano wrote:Hrm,

Looking through my extras folder, I did manage to DL what appears to be a 16k PNG VT of Venus. Unfortunately I'm not sure from where, though I would guess the motherlode. It's definately not on the main site, but you might want to look for it in the "creators" directories...

http://www.celestiamotherlode.net/creators/?M=D

There is a 8k and a 16k venus in Johns directory on motherlode. Unfortunately all venus files there end up with a CRC-error while unpacking. So its better to not waste your time by downloading them.

maxim

maxim wrote:

Kolano wrote:Hrm,

Looking through my extras folder, I did manage to DL what appears to be a 16k PNG VT of Venus. Unfortunately I'm not sure from where, though I would guess the motherlode. It's definately not on the main site, but you might want to look for it in the "creators" directories...

http://www.celestiamotherlode.net/creators/?M=D

There is a 8k and a 16k venus in Johns directory on motherlode. Unfortunately all venus files there end up with a CRC-error while unpacking. So its better to not waste your time by downloading them.

maxim

Thanks alot Kolano! Although the artifacts are very present, the quality of the 16K PNG file is excellent!

Also the 16K bumpmap file is very usable, but both don't quite match so I had to use the transform tool in photoshop to fix that.

Here's a screenshot of the "Artemis Corona". Don't mind the artifacts:
http://home.hccnet.nl/lp.sussenbach/ven ... exture.jpg

Maxim, I had no problems at all with unpacking. I'm not sure if this is a software issue. I used WinRAR 3.42 for unpacking. But it was certainly not a waste of time!

rainman wrote:Maxim, I had no problems at all with unpacking. I'm not sure if this is a software issue. I used WinRAR 3.42 for unpacking. But it was certainly not a waste of time!

I appologize.
After some more tries I managed to get a download with no crc errors. Lately, I downloaded six venus files out of that directory on motherlode and all had a crc error. These were the first bad downloads ever since about 1 1/2 year, so I just didn't take download problems into consideration. Sorry for the misinformation.

The 16k venus however seems to be a /real/ 16k AFAICS. The left third of the map is enhanced, the right two thirds have a lots of gaps and stripes still very prominent. The details of the surface are eye catching nevertheless.

maxim

t00fri wrote:

scalbers wrote:Hi Fridger,

I guess this is all relative as I did remove or reduce quite a few artofacts in the way I combined some of the individual mosaics. Perhaps I didn't look fully at all the links above as I wonder if you might show me a cleaner version existing anywhere that is 4K or higher? Anyone is welcome to post-process my map as well to clean it up a bit. I've had good reviews of this map when showing it to some planetary science folks with our "Science on a Sphere". Perhaps I'll get some time to do some more "homework" though I would also place some importance to increasing the resolution to something like 8K.

Steve,

I guess it's all a matter of one's personal standards. If such textures are to be used for Celestia type software, such artefacts are far from optimal , notably since it's routine work to eliminate them completely ==>



Cheers,
Fridger

Fridger,

I note that some of the other higher resolution images mentioned in this thread also have some artifacts present. I reviewed my software a bit to see if there are any easy ways for me to suppress them. Many of the artifacts are discontinuities between the Magellan data and the underlay (from Calvin Hamilton) that includes other spacecraft. I had adjusted the Magellan overlay based on average brightness and contrast over the entire map. Naturally this broad-brush approach will not allow the brightness/contrast fit to be as good as it could be. Perhaps having a regionally varying brightness/contrast of the Magellan overlay will help it to blend in more smoothly.

I wonder if anyone's actually tried making a full venus map by stitching together the original Magellan FMAPs. I think a complete map would be obscenely huge (it's 75m/pixel) but there are browse images on the Magellan CDs that are smaller.

It'd be pretty tedious to extract those from each of the 10 or so folders on the 125 CDs though and put them together... I did that with a band round the equator once - unfortunately my HDD died and I lost the data

I think the Magellan component of my Venus map is essentially what you describe - this data was put together by Emily Lakdawalla of The Planetary Society. These mosaics are huge (though I recall I had worked with a reduced resolution version of about 2km per pixel). I combined three of them (as mentioned on my website). The Magellan coverage though is only 80-90%. The primary source of artifacts for me is in combining the Magellan mosaics with the data from the other spacecraft (Calvin's Hamilton's map).

scalbers wrote:Fridger,

I note that some of the other higher resolution images mentioned in this thread also have some artifacts present. I reviewed my software a bit to see if there are any easy ways for me to suppress them. Many of the artifacts are discontinuities between the Magellan data and the underlay (from Calvin Hamilton) that includes other spacecraft. I had adjusted the Magellan overlay based on average brightness and contrast over the entire map. Naturally this broad-brush approach will not allow the brightness/contrast fit to be as good as it could be. Perhaps having a regionally varying brightness/contrast of the Magellan overlay will help it to blend in more smoothly.

Steve,

that matches about my own investigations of the matter. But I am surprised why you did not merge the various layers from different sources using standard soft-mask techniques which eliminates such artifacts right from the start.

I think there are two complementary strategies as to textures, depending strongly on their purpose:

--planetary scientists would want to leave such transitions exactly unmodified in order to retain the complete information an image contains. They rather don't seem to care too much about such nasty seams.

--applications like Celestia want to first of all create a breathtaking yet realistic 3d simulation of celestial bodies. In this case nasty seams, stripes and all that are highly /undesirable/.

Bye Fridger

Well, this is a 1k texture of the radar Venus map, modified and cleaned by me, originated from my 4k DDS texture. .



As Fridger correctly says, sometimes it's necessary to add something to the known realty, so I made a long work on the radar map in order to eliminate all the artifacts, defects, missing areas in the original.
Not scientific, but surely more appreciated by a public not particularly involved with Venus science.
Moreover I modified the color because that yellow-orange-red color texture IMHO is absolutely terrible.
If someone is interested, I can upload the 4k.DDS to MotherLode.
Bye.

Andrea

EXCELLENT, Andrea!

I would be quite interested to have a look at the 4k.dds.
Did you correct already for Celestia's center Meridian position which is usually different by 180 degrees from Steve's.

Bye Fridger

t00fri wrote:EXCELLENT, Andrea! I would be quite interested to have a look at the 4k.dds. Did you correct already for Celestia's center Meridian position which is usually different by 180 degrees from Steve's. Bye Fridger

Thank you Fridger.
Sincerely I don't think I made the 180 degrees change, I don't remember it and I've never checked on Venus locations.
Regarding the download, I'll upload it to MotherLode, but to speed up any test you or other wish to do, you can download it now from my web space



Bye

Andrea

No CRC error.But unfourtanetelly all textures are black and white,and for some reason,there is no way to colorize it under Photoshop.Strange,because I had got it before.Can someone help me or give where I can find a color 8k or 16 K Venus texture?

maxim wrote:

Kolano wrote:Hrm,

Looking through my extras folder, I did manage to DL what appears to be a 16k PNG VT of Venus. Unfortunately I'm not sure from where, though I would guess the motherlode. It's definately not on the main site, but you might want to look for it in the "creators" directories...

http://www.celestiamotherlode.net/creators/?M=D

There is a 8k and a 16k venus in Johns directory on motherlode. Unfortunately all venus files there end up with a CRC-error while unpacking. So its better to not waste your time by downloading them.

maxim