October Show Off Thread - 2023 "Creatures of the Deep"

[Agent0013]

I can't use Iray, so I have to work with 3Delight.
What is really crazy is that the caustics work well in Bryce 7.1 Pro with very little effort on the part of the user. It's a program that hasn't been updated in over 13 years!

[Llola Lane]

They all have a price attached, so I would be unable to get them at any rate. I rarely have enough to spend for such products, which is why I am looking for tutorials that explain how to do the effect in DAZ Studio for 3Delight. I found a tutorial that is good for the Iray render engine, but I don't know if it is adaptable to 3Delight. There is so much more that surfaces and lights are capable of for Iray, that are not able to be done in 3Delight. I will be trying to follow that tutorial and adapting it for 3Delight. If it works, I'll let you all know here, and perhaps make a tutorial of my own explaining the 3Delight adaptation of the procedure. It requires the use of certain DAZ Primitives that I did not know were needed. So we shall see how it works out.

You must have posted this as I was posting my last one... lol.  I think you will have the best luck with gobos... I don't think 3Delight does caustic.  It's just a matter of making a rippled water texture to use as your gobo... and then shine the light through it... You'll have to play with the distance of light vs gobo primitive... The artwork I posted first were done before Iray and were FREE cause I made them (the bat... the mermaid ripple).  It will be interesting to see what you come up with. 

[Agent0013]

In the tutorial I watched concerning caustics, though it was for Iray, I learned that just making a caustics textured plane will not achieve the effect, even for Iray. There needs to be a cylinder with about 100 sides, to help with the refraction.


It's similar to the lens model I made that actually magnifies what is seen through it. Setting the refractive index to that of glass worked for that model. the curvature of the surface made the lens refract light like a real lens would. It seems that the refractive index does not work on bump or displacement, as all those textures really do is simulate the detail, and not actually shape the surface polygons. This bears out for my attempts to do caustics that I have tried already. There are other things that are needed to make it look real, besides the cylinder; like a spotlight with the caustics texture on a plane parented to it, rather close up. A volumetric material for the cylinder that makes the environment look as though it has depth haze, also called light absorption. And your scene needs the cylinder to be located within it at a size that makes it appear to be filling the scene.
Another way to achieve the Caustics Effect, would be done with the Underwater HDRI I got for free at Deviant Art. My only problem with that is that I don't know how to import it into DAZ Studio. In fact I haven't learned how to do that with any 3rd party HDRIs! I am currently looking for a good tutorial explaining that.

[jammixx]

Back in the day, I think I remember there were caustic lights.  Daz would have been using 3Delight at the time.  I didn't experiment with them because my computer lacked the power to render the images.

[Llola Lane]

Back in the day, I think I remember there were caustic lights.  Daz would have been using 3Delight at the time.  I didn't experiment with them because my computer lacked the power to render the images.

I posted this on the last page but don't think anyone saw it... these are NOT Iray... https://www.daz3d.com/easy-caustics and https://www.daz3d.com/easy-shadows

[SimonJM]

In the tutorial I watched concerning caustics, though it was for Iray, I learned that just making a caustics textured plane will not achieve the effect, even for Iray. There needs to be a cylinder with about 100 sides, to help with the refraction.


It's similar to the lens model I made that actually magnifies what is seen through it. Setting the refractive index to that of glass worked for that model. the curvature of the surface made the lens refract light like a real lens would. It seems that the refractive index does not work on bump or displacement, as all those textures really do is simulate the detail, and not actually shape the surface polygons. This bears out for my attempts to do caustics that I have tried already. There are other things that are needed to make it look real, besides the cylinder; like a spotlight with the caustics texture on a plane parented to it, rather close up. A volumetric material for the cylinder that makes the environment look as though it has depth haze, also called light absorption. And your scene needs the cylinder to be located within it at a size that makes it appear to be filling the scene.
Another way to achieve the Caustics Effect, would be done with the Underwater HDRI I got for free at Deviant Art. My only problem with that is that I don't know how to import it into DAZ Studio. In fact I haven't learned how to do that with any 3rd party HDRIs! I am currently looking for a good tutorial explaining that.

Not sure what the result woudl be like, but ... starting from a new scene: Create> New Environment Options Node (this will give you the Enviroment properties under the Render Settings tab). Select the Dome options under that, which will show the basic defaults that use the DTHDR-RuinsB-500 HDRI in the Environment map property. If you move your mouse over the tiny thumbnail a larger version of the image will 'pop out' (be warned if you ahve a large HDRI file that can take a bit!!!). If you click on the tiny thumbnail you will see the 'usual' pop-up you'd associate with dealing with a texture map in the Surafces tab. Thus, from that pop-up menu you can select Browse to navigate to where you have the HDRI file you'd liek to use.

[Llola Lane]

Just a note Agent... HDRI's are just background images... they will not put caustics on your subject.  You will still need to add them manually.  I love those water HDRIs... I saw them at DA. 

[Agent0013]

Yes the product is being given away for free at DeviantArt. It is an HDRI for more than just DAZ Studio, but the instructions given are for using it in DAZ Studio, but just one part of it does not tell how to do what the step requires, and there is no way I can find to import any HDRI in the Render Settings tab.
I'll look into what you have told me, Simon, as that was one thing that was not included in the instructions the guy gave on how to use his HDRI.
I do understand that large HDRI's use more processing resources and RAM, and will slow DAZ Studio down. It's a good thing I have a lot of patience. At least from what the guy said, his HDRI is not big on memory size. I have the FMEE Greenhills HDRI, which comes with a 3Delight version and an Iray version. The 3Delight version renders fast as long as I don't have extremely complex scenery added. Sometimes I disable the image backdrop part, and use just the lighting. I'll load a 2D backdrop in the Environments tab as my backdrop image, and make the render aspect ratio match the backdrop image aspect ratio. I then just aim the lighting to match the shadows in the 2d image. It works about 85% to 90% of the time, when I do things that way.
One thing about HDRIs that I figured out is that the lighting is baked into the product, meaning the lighting never changes its position relative to the items in its image background. You can rotate the entire thing, but not just the lights. That is why I usually prefer to do my own lighting. I load lights from the Create menu and edit them myself to do what I want them to do. Caustics is a property of light passing through different things, and casting light patterns on objects the light is shining on. In many cases the items the light passes through has refractive properties that cause the light to get focused or diffused in interesting ways. The refractive index of water causes the patchy patterned look on objects, where the centers of the patches are darker, and the surrounding part around each patch is brighter. The bright part is where the light is being focused. Yes, there are other types of caustics associated with water, depending mainly on what the water is doing, such as in flowing streams, seashore breakers, the ripple rings when something is dropped into a still pond, runnels of water moving down a vertical glass pane, droplets on a surface, etc. Each one has its own caustic pattern, and sometimes there can be a combination of the patterns due to the fact that water can do more than one thing at the same time. An example that is common would be the patchy and rippled caustic combination. That is one of the ones I am most interested in simulating. With the right tutorial I should be able to achieve it. The gel attached to the spotlight would have a combined patch and ripple ring pattern.

[Agent0013]

Simon, in my version of DAZ Studio 4.10, there isn't any item called New Environment Options Node in the Create Menu. This is likely that your version is a much later one than mine. I have not updated to the latest version because it is not compatible with my old PC.

[SimonJM]

Simon, in my version of DAZ Studio 4.10, there isn't any item called New Environment Options Node in the Create Menu. This is likely that your version is a much later one than mine. I have not updated to the latest version because it is not compatible with my old PC.

Ok, that's not an issue - it was an update in recent versions: you *should* have the Environment properties under Render Settings as 'a fixture' - for some reason they decided to make it an 'add in' with that later version.
The main issue you may have is that the HDRI may not have been developed for use within Daz Studio so it may be the 'wrong projection' (not sure of hte correct terminology). The lighting WILL rotate - there is a Rotate Dome property (0 to 259 degrees) by which you can rotate the 'dome' which both alters the view you see of the HDRI at render time but also how the light taken from the HDRI is projected into the scene.