Old 'Opacity' equals what now?

Serefina_Moon

Okie, so I've got an install that works (mostly) of Studio 4.9, and I'm getting to grips with Iray and all the changes,...

I want to make an object in a scene partially transparent, for that SciFi Hologram look.
So, applied an emissive shader to make it glow as a light source, dialled it down to get just the right amount of light, and now trying to make it transparent.
I older versions of Studio I'd just go to the shaders and dial down 'Opaque' until I was happy,... What's the equivalent in 4.9??

I've tried the transucency dial, and it didn't seem to do anything..

Yes, I'm searching the wiki, and just downloaded the PDF, but any clues as to what I'm obviously missing would help.

DestinysGarden

The shader used is more important the version of Daz Studio, but assuming your item is using the Uber Iray shader, you are looking for "Cutout Opacity."

jestmart

Although for the effect you are trying to achieve I think it is Refraction Weight that you will want to play with.

Serefina_Moon

Oh joy,.... User Manual pdf is at ver 4.6...

As the alien guy said,.... rules stuck in comittee...

Thanks guys, I'll check those out. At least getting a plane to be emissive with a starfield map on it wasn't too hard ;)

Oso3D

Cutout Opacity works just like Opacity with a few differences related to Refraction.

In 3DL, to make a refractive object (with UberSurface or similar), you'd set Opacity to 5% and turn on refraction. Maybe set an opacity color to the inverse of desired color coming through the object.

None of that works in Iray. Instead, it's more straightforward -- if you want a refractive object, you set Refraction Weight. A weight of 1 makes the object fully transparent. Refractive Color (or glossy color if you have the default 'share glossy inputs') sets the color of light coming through the object. Refractive roughness (or Glossy roughness, if, again, share glossy inputs) makes light 'blur' as it goes through.

If you want a very transparent object that doesn't affect light going through it much, you can either set refraction weight or lower cutout opacity.

 

 

DAZ_Spooky

Iray shader is here: http://docs.daz3d.com/doku.php/public/software/dazstudio/4/referenceguide/interface/panes/surfaces/shaders/iray_uber_shader/start

Serefina_Moon

Sweet, got it, and thanks!
Left the other PC rendering, might toss the image up to another more mature minded site late if it works - I used Cutout Opacity under Geometry, and it gave me a look that I liked.
I'll try the Refraction Weight method next time, I'm betting that'd get more controlled results.

Oso3D

My big tip about Iray is that it's really tempting to get sucked into trying to realistically simulate everything. There's this 'emergence' appeal of 'well, my image will look right because everything is accurate!'

That's a quick road to frustration and limited rendering.

In real life photography, photographers fake ALL SORTS of stuff to get the look right, from lighting to composition to postwork. Don't be afraid to do the same.

 

I bring this up because I've found that while refractive windows might be more 'realistic,' I often find making a fairly reflective surface with Cutout Opacity works much easier to capture the look people are shooting for.

(Similarly, I've often found it easier to make ocean/lake surfaces as reflective metal, when you wouldn't normally see into the water at all)

 

JOdel

Thank you. I have picked up a number of items over the past year which have only Iray materials. I use 3DLight. Could not find any way to turn off the material zones other than to apply a 3DL shader to one which usually brings back the opacity slider.

Oso3D

Aaah. I would probably recommend converting those materials to 3DL anyway, I'm not sure if DS needs to do anything special.

I've had reasonably good luck converting Iray materials to 3DL; Iray shaders typically don't use special code or anything. The biggest problems you can run into is when the Iray texture maps have different tiling, and trying to translate things like top coat over. (I generally find it easiest to simply make a geoshell, a second layer I can manipulate directly)

 

McGyver

A while back I was trying to light up parts of a facade texture to simulate lit up windows, so only part of the texture would be emissive... That's probably not similar to what you are looking to do, but I think my problem was I was getting the effect you are looking for, before I figured out how to get the effect I wanted... I haven't read the thread in a while, but here it is in case it could be of use to you somehow... http://www.daz3d.com/forums/discussion/57336/emissions-mask-map-or-something-like-that-solved#latest 

 

Edited to Add-       Nevermind, I didn't realize this was solved.

Serefina_Moon

Never got around to adding another Thanks here for you Oso3D ;)

Though my recent experiences, and given my PC is waaay in need of an update - i7-950 / X58 / GTX470OC for the screens and GTX760 for the GPU/Cuda cores,... I'm finding that when I mix 3DL and Iray shaders, especially 3DL clothes under Emissive lights in Iray render, Studio will crash out.
Pretty much convert everything to Iray shaders now, takes a little longer, but crashes less :)

No doubt it's a problem that will go away when I update the PC, probably when BMD updates DaVinci Resolve again.

grinch2901

Oso3D said:

I bring this up because I've found that while refractive windows might be more 'realistic,' I often find making a fairly reflective surface with Cutout Opacity works much easier to capture the look people are shooting for.

(Similarly, I've often found it easier to make ocean/lake surfaces as reflective metal, when you wouldn't normally see into the water at all)

Amen! When I render anything with Iray based glass shaders applied to the windows, I tune them they way you suggest. For two reasons: first, it's a load faster to make them shiny yet mostly transparant and second, it rarely matters in the image for the windows to be physically "correct" like a real window.  I'll take the speed almost every time, unless a character is standin directly in front of a window or something that makes the window the prime feature in the image.  Which is really rare.