GRS In Stellarium

[Guest AstronomyShed]

I've just posted this on my site but thought some of you could use it here too :-

Wouldn't it be good if you could set Stellarium up so that the GRS is in the right place in the software as it is for real?

Well the good news is you can, the thing is, the GRS is a storm so it's subject to a bit of movement over time, unfortunately, stellarium doesn't adjust this in updates etc, but you can do it manually. here's how for XP

In XP you need to have the view settings to show hidden files and folders.

Firstly, i reccomend you download a program called 'notepad++' the reason being, that windows notepad is actually a bit poor at editing code, EDITING CODE!!! I hear you say!!

Don't worry, it's simple, so, notepad can screw code up and misplace lines and save in the wrong format and allsorts, so, download notepad++ from here :-

http://notepad-plus-plus.org/

Once installed, you're going to just have a quick check of a website for transit times, so put in your correct time zone here :-

http://www.skyandtel...html?page=1&c=y

This will tell you when the red spot transits Jupiters meridian, ie, it's in the middle. So make a note of the times, all you need this for is to double check your edits have worked ok.

Next, go to the following location, C:Documents And Settings <folder with computer name or your name>Application DataStellariumData

Now in that Data folder you will have a file called ssystem.ini

Right click it and select "edit with notepad++" (you did install that earlier didn't you?)

Scroll down the list and you will see a section that looks like this :-

[jupiter]
name = Jupiter
parent = Sun
radius = 71492
oblateness = 0.064874
halo = true
color = 1.0,0.97,0.89
tex_map = jupiter.png #texture courtesy of Björn Jónsson
tex_halo = star16x16.png
coord_func = jupiter_special
lighting = true
albedo = 0.51
rot_periode = 9.927953
rot_rotation_offset = 105 #just some value good for GRS #old:151
#rot_obliquity = 2.222461
#rot_equator_ascending_node = -22.203
rot_pole_ra = 268.05
rot_pole_de = 64.49
orbit_visualization_period = 4331.87
atmosphere = 1

Now in the above, the part you want, is "rot_rotation_offset = 105 #just some value good for GRS #old:151". In yours it will probably say offset = 250, like this :-

"rot_rotation_offset = 250 #just some value good for GRS #old:151"

Change the '250' to '105' and then at the top left in notepad++ click FILE and then SAVE. Close notepad++ and start stellarium.

Advance the time in stellarium to a time when the above site says there should be a transit, zoom in on Jupiter in Stellarium and now the GRS should be placed around the middle.

all done

Any problems, just ask.

Edited December 22, 2011 by AstronomyShed

[Craig]

Thanks for posting this, very informative. I had no idea Stellarium could do this.

[Guest AstronomyShed]

There's lots you can do with it, including reducing it's cpu/gfx overheads, I think the most common mistakes people make though are editing files in notepad which is a pain as it reformats layouts and word wraps etc wheras notepad++ doesn't, it's a LOT better than notepad, also stellarium has several .ini files, many people assume they are just in the stellarium program files folder, but those are just backups, in effect, the defaults and not what stellarium actually uses, you need the folder I pointed out above to make the edits. I'll post the overhead cutting edit as well in another thread.

[Guest AstronomyShed]

OK, this one will fix two potential issues, some people have an issue with the screen flickering if they load stellarium fullscreen, this isn't a cpu or load issue, 9 times out of ten it's a resolution issue as stellarium has a set video resolution that is different than your monitor or gfx cards native. the second fix is to reduce overheads, Stellarium tries to refresh the screen as fast as it can, it's just not necessary, not it has two refresh rates, one at idle, meaning when the stellarium window isn't active, (when you're not actually using it and moving things about) and one at active, which is faster, in other words trying to redraw screen as fast as possible when you're using it and moving things about, but these can be reduced drastically to reduce load.

Both tweaks are in the same section so it's nice and easy. Firstly, right click on an empty spot your desktop (this is XP again) Click 'Properties' and from the window that opens, click the 'settings' tab. On that screen you will see your video resolution, write this down.

Next, go to the following location, C:Documents And Settings <folder with computer name or your name>Application DataStellarium

In there you will see a file called 'config'ini' right click it and select 'edit with notepad++

Look for this section :

[video]
fullscreen                          = true
horizontal_offset                   = 0
maximum_fps                         = 25
minimum_fps                         = 5
screen_h                            = 1080
screen_w                            = 1920
vertical_offset                     = 0
viewport_effect                     = none

Now, set 'screen_h' and 'screen_w' to the figures you wrote down from your desktop. next, go to 'minimum_fps' and enter a figure of 5 like in mine above, now 'maximum_fps' I have set at 25, but there's room for experimentation here, you could go as low as 10, basically lower it, then save, then launch stellarium and play about with it, if it's choppy on movement then just up the 'maximum_fps' a bit, I think by default it does something stupid like 10,000 fps which is obviously eating away at your system resources.

NOTE

You MUST make any edits whilst stellarium is NOT running or it won't save the edits as the file is in use by stellarium.

[Doc]

I never knew either Dion. I really appreciate this thanks very much.

[Guest AstronomyShed]

Hidden features Mick if you find the '105' setting for GRS doesn't put it in the right place, just tweak the figure a bit to rotate the Jupiter graphic a touch more or less.But 105 put it 'spot on' for me, (pun intended)

Edited December 22, 2011 by AstronomyShed

[Doc]

Ain't it strange why they make them hidden features. Next time I'm out I'll try this.

[red dwalf]

very usefull thans DIon