OTOY Forums

Hi Juan,

I have noticed that certain scenes when rendering in Lightwave using 1.5 final are very overexposed. I have to dial down the exposure to match the previous plugins renders, but this is not an entirely accurate solution. Any ideas / solutions?

Thanks for the hard work!

I am not sure, I don't see this problem here. Perhaps a gamma problem? ... check that your scene has the Lightwave color space functions set to linear, and also check the gamma settings of the Octane scene.

-Juanjo

Please see attached zip for exactly the same scene rendered using:

01.) Octane-for-LW_1.25.0_Windows and 02.) Octane-for-LW_1.50.0_Windows

All settings are identical, yet the image rendered using 1.5 is overexposed.

Now the manual has some info re. the projection node, I'd thought it was time to have another look.
The xyz - uvw option only maps along the Z axis. How would you project from the y or x as well? You have to use the UV translate/rotate/scale options in the texture image node, not the projection node, so units other than scale are not available. The manual does outline this, but this is a bit of a limitation (The projection will map image textures to the (-1, -1)–(1, 1) range.)

That brings me to the fact the UVMAP node is deprecated. As it stands the projection node does not offer the same level of functionality (or ease of use? unless I am missing something) as the UVMAP node, in particular being able to use the LW T data. I've been opening older scenes and updating assets for use in Octane. Several of these have a single projected or cube mapped texture, which means all I have to do is add the UVMAP node, set it to LWT, and I am done.

Hopefully the plan is to leave the UVMAP node in place for the time being?

I am not sure about why do you want to work with the xyz-uvw projection, why not use the box projection?

The UVMAP node is not going to be deprecated anytime soon, at least it is going to be in the plugin along the 2.x cycle

-Juanjo

Hi Juan,

Have you managed to look at the zip I uploaded a few days demonstrating the exposure issue?

Thanks,
Carlo

Hi Juan,

I guess I am use to planar projections for logos etc on products. I'll have another go with box projection, keeping in mind I dont want the image projected from 3 axies.

Does the box projection use a different co-ordinate system to LW? Is zero in a different place on the image?

Cheers,
ANdrew.

Godstrike wrote:Hi Juan,

Have you managed to look at the zip I uploaded a few days demonstrating the exposure issue?

Thanks,
Carlo

Opps ... sorry, I forgot it. I am just testing it now, but I am not sure what could be the problem.

-Juanjo

gristle wrote: Does the box projection use a different co-ordinate system to LW? Is zero in a different place on the image?

I am not sure, you should test it. I think that at the begining the box projection was the same than the LW cubic mapping, but there was a lot of changes in this node, so now I am not sure.

-Juanjo

Godstrike wrote:Hi Juan,

Have you managed to look at the zip I uploaded a few days demonstrating the exposure issue?

Thanks,
Carlo

Ok. I have found the problem. Octane 1.25 has a bug that limit the max. power in the textures to 1.0, even if you put a greater value in the power parameter.

In your environment texture you have a power of 5.0, but for Octane 1.25 the limit is 1.0, so if you put a power of 1.0 in the Octane 1.50 you are going to get the same image.

-Juanjo