LWF Test Results

Hi All,

I was having some problems with dark shadows with the Sun/Sky system and Physical Camera recently:

http://www.chaosgroup.com/forum/phpBB2/viewtopic.php?t=19430

So I’ve decided to have yet another attempt at LWF with these results:

I. No Gamma -

II. 2.2 in Viz Pref’s, no Colour Correct Plug-in -

III. 2.2 in Viz Pref’s, 2.2 in Vray colour mapping, no Colour Correct Plug-in

IV. 2.2 in Vray colour mapping, 2.2 Colour Correct Plug-in

In example IV the slot in the material editor becomes almost too dark to see the material.

Any thoughts and/or pointers would be much appreciated.

Trev

I am trying to learn this LWF stuff too and am experiancing some level of difficulty. Just a thought for you though, have you put 2.2 in the bitmap import in the max/vix preferences?

Yep, did that. :slight_smile:

Uncheck affect MatEdit ? Correct would be to change the Example Scene for the MatEditor to be a LWF file with proper lighting etc.

Regards,
Thorsten

Did you check this out:
http://www.chaosgroup.com/forum/phpBB2/viewtopic.php?t=17824

3 and 4 look good to me - I take it that you’re using a simple colour swatch for the yellow tube on the left? If you use the preferences based gamma there’s an option for it to affect the colour pickers and material editor so it should lighten things up a wee bit.

Yes simple colour for tube. Affect colour pickers and material editor does not appear to be available in Viz…must be a max thing.

Sorry…not sure what you mean?

:slight_smile:

Well the sphere in the preview is basically a max scene that is loaded to render previews. You can override that scene to render a different one in the material previews. If you prepare a very basic LWF file then the MatEdit results should look a LOT closer to the final look.

Regards,
Thorsten

I see… :smile:

Also, depending on what VIZ version you’re on, there was a bug in Viz 2007 where gamma correction wouldn’t get applied to the material editor shaderballs… the fixed it in the silently released service pack 1.

This is a very good place to start…I didn’t have a whole lot of luck with LWF until I checked out Lele’s stuff.

This is my favorite LWF tutorial that came out shortly after the famous Throb LWF tut (which is good as well):

http://www.gijsdezwart.nl/tutorials.php

The third diagram/method is the most clear to me. Don’t worry about the AIM RGB stuff.

Thanks (once again) Clifton,

Seems I may have finally got this into my thick scull (nervousely awaits replies to the contrary). Set max (Viz in my case) preferences as your link, save image from max frame buffer (if it makes a difference - didn’t turn on the VRay FB) as an EXR file.

This I can open in PS, convert to 8bit when happy and save as any file format with a small file size for comping etc.

:smile:

Yes, my gamma settings are as per the tutorial (except I use Max so I also enable the material swatches and color picker to be gamma corrected). After setting them, just work as normal in the MFB. Save the result as a 32-bit EXR and open in PSCS2 or better. It will appear (almost)exactly as in MFB. Voila, you are using LWF.

If you start a file from scratch, all should work well. Your lights will not need to be as bright (which means faster renderings with GI), and you can put inverse square falloff on Max lights and they will look correct! You may want to darken old materials that use the color swatch for diffuse color, such as metals.

With this method the only time you have to gamma correct a material is if you are using solid color swatch and you need to match a specific RGB value. You would need to put the Color Correct modifier in the diffuse slot, specifiy the color in the color swatch inside it, and set it to a gamma of 2.2

Also, if you don’t want to save as EXR, you can save your output in an 8-bit format such as JPEG if you click Override and specify 2.2 in the save settings.

i find saving to EXR very convenient as i get much more control over the image afterwards in PS CS2…even if i use clamp output

Martin

After looking at the pictures I am going to try and LWF process a go. Just a quick question for you guys. As I have CS2 installed on my machine, AdobeGamma loads on windows startup. Is this in any way going to interfere with the Max and Vray gamma settings?

Thanks for posting your results TcT. Any chance you would be willing to host your demo scene so that I could download to try your settings out?

Cheers,
Jason

Clifton,

Thanks once again for you help with this. Very much appreciated.

@ loafer87gt

I’m affraid I don’t have the facility to upload a scene to the web.