I did a few things in order to achieve the look. Moved the star closer to the planet, turned down the star temperature to adjust the colour of the image, thickened the atmosphere a bit, and turned on the experimental clouds. After that, it was about finding a nice place to take the screenshot from, drop the sun to the horizon, and adjust the atmospheric settings to get an appealing composition.
Happy to see everyone enjoying them, even if they`re just screenshots for now. 
Well I I was mostly interested in how you guys are dealing with atmospheric composition because in my work almost every atmosphere comes out more or less like this
why I find your pictures very impressive
PS please don’t look at the ground it’s way broken because i’m working on it atm as I took this screen
What kind of scattering equations are you using?
Recheck your scattering equations and their inputs. Looks like your atmo looks good where there is ground behind it. When its just space it suddenly gets really thick.
Another possibility could be that the atmo is blooming way too much since your sun is blooming like crazy.
i’m using a model based on of O’Neil scattering shader I patched the star color but I got stuck there as I had no idea how to input atmospheric composition into the mix
now that you mention that I recal INova changed to an other type equation sometimes in the last two years
@INovaeJan
ya my Esun is way over the top at 654 in this particular one but I suspect part of the white band should actualy be behind some of the ground and because my ground is currently in pieces it makes the thing worst
I can’t help you with the shaders, since I don’t do graphical programming. All i can do is hit you with some physics.
Your atmosphere looks like it’s the core of a lightsabre. How much light is that star pumping out? What’s the brightness at the planet’s surface? And what does the star’s colour spectrum look like?
I don’t know too much about graphics, but that is a lot of bloom. The atmosphere looks like it is emitting just as much light as the sun.
that’s fair enough I can deal with the programing if hijacking the INovae screenshot thread is fine
the physic of the scattering model is basically summarized there
http://http.developer.nvidia.com/GPUGems2/gpugems2_chapter16.html
how much light the star is pumping out? probably way to much in this algorithm I think a ESun value of 100 was the standar to make a earth like planet mine is 6 times that
but then again I would need to make a good read on how much light different types of stars output and how that scales with distance from the star to push the model further
The equations look right, though they don’t give the equations for K(lambda). I assume they’ve done it properly.
The intensity of the light decreases as 1/distance2
I have radius and temperature for now but i’d like to add more to my model
1/distance2
in what unit do we need the distance for it to be valid
Doesn’t matter, really. You can use inches if you like, or atom widths if it suits you; as you double the distance, the intensity of the incoming light will be cut by a factor of 4.
The astrophysical equation is:
F = L/(4pir2)
Here, F stands for radiative flux, which is the intensity of the light in watts per square metre (W/m2). L is the luminosity of the star, which is the total power output in watts (W), and r is the radius of a sphere centred on the centre of the star, measured in metres (m). This could just as easily be measured in calories per square league, so long as you convert the values properly.
Another thought comes to mind, too. What’s the density profile of your planetary atmosphere look like? Is that something you’ve coded in directly, or are you solving the hydrostatic equilibrium equations?
good i’ll plug those in and see what I can get
the density profile is predefined in the equation to give a result similar to earth I can’t find the original paper by sean O’Neil describing what he did.
Alright. Try returning the star’s luminosity to solar values, and play with the orbital distance of the planet. Also, try to get the sun’s light to pass through as much atmosphere as you possibly can to check on how effective the scattering is. We wouldn’t expect views like yours above, where we can see the sun above the atmosphere, rather than through the atmosphere, to show much reddening at all. If anything, the blue tinge that we see is the expected result, since the atmosphere is scattering that blue light, and sending it out into space, in all directions, while the red light continues to pass through the atmosphere.
The hydrostatic equilibrium equations can be solved for the density profile of an atmosphere. The result is:
rho(z) = rhos * e(-int(z/H(z)))
rho(z) is the atmospheric density at height z above the planet’s surface.
rhos is the density at the planet’s surface
H(z) is the scale height of the atmosphere (the height at which the density has dropped by 1/e)
int() is the integral, here taken from 0 to z
H(z) = (GM/rs2) * 1/(R*T(z))
G is Newton’s gravitational constant
R is the ideal gas constant
T(z) is the temperature at height z above the surface
rs is the planetary radius
You may want to consider allowing rhos and H(z) to be input parameters. It will let you easily change the density and scale of the atmosphere, and hopefully give you a clearer idea as to whether everything’s working as it should.
Looking at your pic, I’d say the atmospheric scattering model looks almost correct. It’s supposed to look like this without HDR. So I’d say what you need is a way to tone map the results. If you’re already using HDR, then yeah it might be a problem with your scattering model.
Thanks all for the help
I have HDR but I don’t have tone mapping yet
I seriously think your biggest issue is that your star is too bright. Bring its luminosity back down to solar values, and then move your planet away in regular steps (maybe doubling the distance every step, for instance) and take some screenshots. See if there’s a step where things start to look the way you expect them to.
Because you asked this, I want to offer a word of caution.
Your units must be consistent. If you use meters, use them everywhere. Not miles, inches, kilometers or light years. Use meters. If feet, use feet everywhere. When thinking about this, it is an obvious thing, but if you don’t think about it it can slip by.
It slipped by me when I started working on flight simulation back in the 80s. As a result, I made a hash of the equations and nothing ever seemed to work right. Hey, I’m a logic guy…
Also, don’t use miles, inches or feet. Almost the entire world has switched or is switching to a more efficient, rational and all-around better unit system(¤), and for good reasons.
And “almost the entire world” include NASA, a growing part of the US industry and military, (officially at least) the British government, and every single other nation (bar two officially, but probably not for much longer).
Yeah, I cringe every time I see Imperial units in SF/space-related stuff less than a century old. You wouldn’t be cruel and want me to cringe, would you? 
(¤) Utterly objective statement that is not biased in any way by familiarity with said other system. Really.
@Kichae your equations helped me I scaled the luminosity to some valid value and understood why my luminosity didn’t scale properly with distance the result are somewhat closer to expected but when those values are valid getting a non transparent sky is almost impossible this is a planet around a red star after the first part of the tweaks now I’m going to try to include the hydrostatic equilibrium equations
@JB47394 my units are consistent internally but some equations expect a a certain unit so I had to be sure I would not feed it meters while it’s expecting KM or AU
@ThornEel i’m not from the USA so no risk
I just realized that I had a typo in my hydrostatic equilibrium equation.
rho(z) = rhos * e(-int(z/H(z)))
should be
rho(z) = rhos * e(-int(dz/H(z)))
The temperature profile of real atmospheres tends to be really complicated. Choosing a simple function for T(z) will help you do that integration in the exponent (since H(z) is a function of T(z)). In fact, you might be safe choosing an isothermal atmosphere (T = constant at all heights). This reduces that integration to int(dz/H, x = 0, Z) = Z/H, and simplifies the density profile equation to:
rho(Z) = rhos * e(-Z/H)
where Z is a height of your choice (I assume it’ll be whatever you’ve chosen the top of your atmosphere to be; make sure the density at that height, rho(Z), is negligible.
Just FYI, the isothermal density equation is actually normalized to the surface values you choose, so just like the stellar luminosity-radius-temperature equation, the units don’t really matter. Just so long as you use the same units for H and Z, and rho and rhos, you’ll be fine. Standard mks metric units are a safe choice.