mr physical sky custom background

[Er1Ck]

Dear CG mates,

 

I recently graduated and just started my own architectural office. My first assignment is a design for an industrial complex and my client asks for 3d visuzalizations. I learned a lot the last few weeks about mentalray in 3ds max, and i decided to work with that. I already have nice images but like to take them to the next level.

 

As backgrounds I just made planes and sticked a random sky texture to it. This works, but with different cameras this is not very efficient. I had to put them in different layers and made scene states to quickly hide and unhide them with the different camera positions. Apart from this, its only workin when the daylight is in front of the plane and there is no good horizon..

 

Now what i need is a technique that works with mentalray, with the horizon and if possible different skies for different cameras (means that i dont have 6 exactly the same skies when i have 6 different camera positions). Most of the tutorials make a sphere and paste a 360degree sky in it, but as far as i know this doesnt work with the mr physical sky horizon and also doesnt work with the daylight (everything is black, since the sun cant reach it).

 

What is the best way to treat the sky? and does anyone has a link to a tutorial or (e)booktip?

 

Thanks in advance,

 

Erik

 

PS i already googled and checked this forum the whole day and didnt find what im looking for..

[CJI]

If you want to use the sky map on a sphere method then apply your sky map to the half sphere.

Right click on the sphere and untick casts and recieves shadows. This will let the direct sunlight and ambient light pass through the dome from the physical sun & sky while using the sky map for the reflections. You could also place the sky map in the Haze perameter of the physical sky and do away with the dome sky all together.

 

If its just for a background could you do it in post in photoshop instead?

[Er1Ck]

If I put a skymap in the haze at the physical sky, i never get white clouds, they always turn blueish because of the haze

 

no matter how hard i google, there is apperently no good and quick way to get a good environment background. i cant find a single tutorial which helps me. pretty frustrating because i know it should be possible.

[Justin Hunt]

the sky map in the haze slot isn't a good way of going as , as you have noticed, it just blends your sky map with the mrphysical sky map.

 

Try using a HDRI or as uddie suggested using a hamisphere with a map.

 

The most efficient methode is still comping in photoshop.

 

jhv

[Justin Hunt]

google master Zap, Jeff Patton and Brian Bradley (mental bout Max) they all have fantastic tutorials for mentalray and excellent blogs too.

 

jhv

[CJI]

HDRI and comping in photoshop is probably still the best way to go but i have had some good results with the map in the haze paremeter.

 

Sorry i couldn't post the full image the project hasn't been approved yet.

[berliner]

in the Environment dialog drag an 'instance' of the mr physical sky from the Environment map into your material editor. In the mr Physical sky parameters, disable 'inherit from mr Sky' to break the link from the mr Sky parameters of the daylight system. YOu can then lower the 'Horizon height' to something like -1.5 or so- depending on where you actually want to see it.

Then, click on the map button next to Haze value. Select the bitmap you wish to use. In the coordinates rollout, click on Texture and make sure Use Real-World Scale is off. Then set the coordinate to Environ. and use Screen. Change the Blur value to .5 to sharpen the bitmap. In the Output rollout, change the RGB Level to 10 so that you can increase the intensity of the bitmap so it doesn't get lost in the color generated by mr Physical Sky. I'd play with this value to get the desired result. If the color looks off, click on Enable Color Map and you can further adjust the curve points to bring out the highs and lows.

 

Hope this helps.

[berliner]

One more thing, in the Non-physical Tuning area, change the Red/Blue Tint to like -0.2 and decrease the Saturation to like .75.

 

These settings worked for me and the sky turned out great.

[thorsten hartmann]

Hi

 

this is a Problem of physical Scale. It gives different Way´s...

 

a) set the Physical Scale

b) Set the Amount Value of your HDRI

c) at 3dsmax 2010 work the Functions "Procces Background and Environment Maps", but this work not with real "Depth of Field".

c) use Photo Studio Pro, that have a "automatic physicale Scale" Function. That work with real "Depth of Field".

 

mfg

hot chip

[Peter M. Gruhn]

Another option.

 

Put your map in the Background: Environment Map slot.

Turn off Process Background.

Select the sky. Turn off Aerial Perspective.

[DanGrover]

To be honest, if you're going for a realistic render - and mr sky suggests you may be - you'd probably want to actively get rid of the horizon really. You can never see it in real life unless you're on top of a mountain (though even then, you're usually surrounded by other mountains!) or in the ocean, but again, you never really get that hazy horizon that you do in mr sky.

[_intrepid_]

Hope this isn't to late to help,

but I found a few wideos that were really helpful

 

Just search for

Ethan Janssens mental ray sky part 1 ( 2, 3)

I've found them on mymentalray site

 

those are three fairly short, but very helpful videos, concerning the MR Sky...

[RevitGary]

I have been struggling with this for a while with a night scene and moon.

I came up with a solution I havent seen anywhere.

 

I raised the horizon to 30 feet and added my moon sky jpg as a ground image.

This was simple and direct. I am really happy with the results.

I just thought I would share. See if it works for you!

 

Let me know what you think

Edited May 16, 2010 by RevitGary

[pixelperfectg]

Or, if you want to use a photo for the background you could always simply assign it as the environment instead of the mr physical sky.

Edited May 18, 2010 by pixelperfectg

[RevitGary]

Will that give you the same lighting as a physical sky? just with an image in the background?

[pixelperfectg]

Depends on how you have your scene lighting configured. If you're using the 'typical' daylight system with the mrSun/mrSky then yes, the lighting won't change regardless of what you use in the scene background because the scene background has nothing to do with the illumination. The only time the scene environment comes into play with the scene lighting is when you use a setup like a skylight that's configured to use the environment for it's color.

[ramy]

Along with a skylight you can use the environment/background switcher shader in your environment. You can plug the same hdr map in all of these slots, but tweak the intensity separately to get your environment colors and reflections from the environment.

[xenomyosin]

Hello guys,

 

This is an easy way to use photographs for MR backgrounds:

 

1. Copy your mr Physical Sky into a material slot

2. Turn on 'Use Custom Background Map' within the mr Physical Sky parameters

3. Plug your image into the empty map slot

4. Go back to your environment dialog and change the physical scale to unitless

5. Change the unitless value to 150000 (the higher the value the brighter the output)

6. Render the scene

 

Good luck,

 

 

Simon Blakeney

[Bundie]

xenomyosin

 

thats a great method which ive used berfore, just be careful to anyone using VUE inside MAX, cause it renders all VUE elements white

[Bundie]

So if supplementing the mr Physical Sky in the environments tab with a Image for the background and setting it to screen. How do we avoid reflections been the same as the background?

 

My reflections are using the same screen as my Background Screen