REQUEST: Octane render calibration pre set

Ingemar Lundgren

Any plans for adding calibration pre-sets for Octane render? Growing number of users and i have seen on Octane forums quite a few are using DDO but sonme have problems getting the same look as in 3DO.


If not wich claibration pre set would work best with Octane render? I have tried one of the PBR ones and it seems to work ok.

Eric Ramberg

Yes there are plans or adding support for it! Im not an octane user myself so I cant really say what profile would be the best. But if there are people here on the forums that have tried some profiles or have any insights to how octane behaves it would help speed up the process greatly!

alecmorris

So, the problem is IOR is key to Octane, and at the moment it is a slider that can't accept a texture input. So you have to use an octane mix material and a mask to deal with something like a painted metal.

The devs have mentioned in the forums that they might add the ability to insert an IOR texture in an upcoming release though. Maybe you guys could get in contact with them, I think they'd be happy to work with you. Octane really is perfect match for DDo.

Let me know if there's any other way I can help. I plan on using DDo/Megascans as a big part of my Octane work.

Ingemar Lundgren

Ok, i see. The IOR issue is a general problem with Octane i guess.

Did some test today and this is the closest i got to matching 3Do. Hard to set up the light the same of course. HDRi enviroment map on the Octane render frame. Looks a bit more stylized in 3Do and more natural in Octane but i prefere the 3do look. Guess i need to tweak more in Octane as it looks a bit dull. Any tips greatly appreciated. Can post my node set up if you like. DDO did a great job with the spec map making the coroded green copper areas non specular. On this model i think it worked well.

The 3Do version is picking up a lot more fine details on the horn (bone) and on the metals. Partly due to the dull even lighting i set up in octane but i can never get this detail in Octane. tried several light set ups.

I made this texture in like 4min in DDO. I am pretty excited about that! If it could only be more stable..

First image is 3Do and second Octane

Gordon Robb

The only thing I have sussed is the need to use a calibration profile with a roughness map (rather than glossy). As far as I can see this is just an inverted glossy map, but not sure.

Ingemar Lundgren

Have only done some trials on one model so far. Plugged the glossy in to the roughness. Worked fairly well except for one of the metal materials. I had to adjust that part of the glossy bake in photoshop manually
Seems like the glossy map almost works for roughness. Would be great if it worked with out needing tweaking.

Gordon Robb

Check the glossy maps. Any of the profiles I've looked at have the shiniest bits (chips along a worn paint surface for example) as white. However, in Octane they should be black.

alecmorris

Gloss and roughness are the same thing, just inverted. You can actually tweak it in octane using a mix texture. Use the map to define two scalar values that will become the black and white point. Even if you're going to adjust it in Photoshop, this is a way to tweak it in real time and figure out how you need to adjust it.

Diffuse, spec color, roughness, and normal/bump/displacement (you can only use one in octane currently) are the inputs I use from ddo. Then I use IOR to define reflectivity. Ingmar, that might be why your metal material looks off. Most things are in a very narrow IOR range, except for metals. Also, on the images you posted its hard to tell without looking at your hdris, but it's possible your linear workflow is off. Remember that octane expects everything to be ready for a linear workflow, so if you import rgb textures that aren't properly corrected, you'll need to adjust their gamma in octane to 2.2.

Remember though, IOR won't take a texture input. So for something like a metal with a plastic coating, you will need to use a mix material and a mask to get the right look for the two layers.

Ingemar Lundgren

Thanks Alec for the tips. Done some more tweaking now. Looks like you and Gordon are correct that the glossy works well in Octane roughness if inverted. Did that and tweaked it with color coreection texture. Plugged in to the diffuse input first so i could visualy see the difference of the color corerection. Worked well.

The dull metal was caused by a HDri enviroment texture that was not realy a proper HDRi i think. On the right track now i think.

What would be a good IOR for wood btw?

alecmorris

i usually give wood an IOR in octane between 1.5 and 1.8 depending on what state its in. Really, most stuff you're gonna make, like plastics/concrete/leather/rubber will have an IOR between 1.3 and 2ish. 3+ are metals. Chrome will be around the max in octane of 8. Something less reflective like silver would be around a 4. Just remember that once you get into metals, the color will be defined by the specular color, not the diffuse.

From there, the roughness and bump/normal/displacement become really important into defining the look. The difference between an archviz wood floor and a dirty, rotted wood is going to come from those.

Gordon Robb

Alecmorris: I think the objective for me would be not having to tweak the spec or glossy moas. However, can you tell me more about this method of using scalar inputs for black and white point?

Ingemar Lundgren

Appreciate you help Alec. The Octane forums are not very active so hard to get advice there.

For metal i have always used Glossy shader with IOR set to 1.0 and if i want to make a cooper like material i plug a bronze colored spec map. I have also used dirt material with for example rust plugged in to diffuse and metall spec to glossy map.
I guess my node set up is not very good? You are using specular material for metal? Could you explain how you set up a metal material?

Gordon Robb

ingemar: you can learn a lot about setting good shaders up by looking at the LiveDB materials in Standalone.

Ingemar Lundgren

Yeah i have checked the Live DB materials. The metal ones that i checked all had glossy shaders though. I thought specular shader was only for glass and transparent materials. Will check more materials to learn more.

Gordon Robb

I do t think he's using specular. By IOR, I think he means the Index parameter,

alecmorris

@gordon Robb, I plug the roughness texture in AS THE MIX in the mix texture node, then 'mix' between two shades of black/white/grey that essentially become the black and white point. This way I can use those two shades to set my black and white point in Photoshop with no guessing, because I've already seen it in octane. You could also use the clamp node I believe to set the black and white point if you don't want to permanently change the map in Photoshop.

@ingemar I use the glossy material, Gordon is correct. Index is the I in IOR. I'm currently expanding my render computer (2 sc Titans and 4 6gig 780s!!!) so Its currently in pieces, but it should be all together next week. I'm just waiting on my 6 gpu case to come in. When I have it all set up I can show you how I make a metal if you'd like.

Gordon Robb

@alecmorris: sounds ingenuous. Must try it. I'd still like dDO to kick out a roughness map that just plugs in and looks pretty much like it does in 3DO