Tutorial Needed for VRay Dome Light + HDRI

[marcdevon]

Dear Group,

I am attempting to render a scene using a Paul Debevec HDRI given here:

http://gl.ict.usc.edu/skyprobes/

using VRay 1.5. It is my understanding that using a HDR in conjunction with the VRay light allows for the HDRI to act as a direct light (i.e. cast shadows). I have had some problems with achieve my desired results. I remember seeing a video that vlado produced demonstrating this new feature. I used the following hdri map from the collection:

probe_12-10_anglemap.hdr

Here is my result:



As you can see, there are no direct light produced by the HDRI. I took a look at the frame from vlado's animation and the map did produce a shadow. Can anyone here create a tutorial or provide some tips as to how to use this feature. The VRay 1.5 user's manual really doesn't provide much direction. I think it would be a good idea (for posterity) for creating a tip/tutorial for a small interior scene along with an exterior with a huge sky hdri map. I tried tinkering with many parameters but I got nowhere. Can anyone help?

Thanks

Marcus

[percydaman]

what kind of vraylight are you using?

[Paul Oblomov]

Well, seems it depends on what HDRi you're using. To see bright direct shadow you need at least a bright spot there. IMHO

[marcdevon]

what kind of vraylight are you using?

Hey percy

I am using a VRay dome light.

Here is another render. Pretty much the same results but I changed the ground material

[marcdevon]

Well, seems it depends on what HDRi you're using. To see bright direct shadow you need at least a bright spot there. IMHO

Here is the map that I used with this scene (it should be noted that I used the hdri version):



As you can see, there is a bright sun present within the hdri. Furthermore, if you look at the corresponding frame within vlado's time lapse animation, you will see that the bright sun is clearly contribution to the rendering.

I must be doing something wrong but I can not figure out exactly what that is. Since this feature is new to me, I do not know how to set many of the associated parameters for the VRay dome light + hdri. For example, what are "proper" values for the photon emission target and emit radii for a scene such as this. I am hoping that someone who has used this feature can provide some direction.

Marcus

[RErender]

1. Load the skyprobe hdri with the VRayHDRI map
2. set too "mirrored ball" map type
3. Set multiplier in VRayHDRI to .003 (this is in 2.2 gamma space)
4. Create a dome light.
5. Under "dome light options/texture" instance the VRayHDRI from above into the texture slot of the dome light.
6. Hit render

[marcdevon]

1. Load the skyprobe hdri with the VRayHDRI map
2. set too "mirrored ball" map type
3. Set multiplier in VRayHDRI to .003 (this is in 2.2 gamma space)
4. Create a dome light.
5. Under "dome light options/texture" instance the VRayHDRI from above into the texture slot of the dome light.
6. Hit render

Just tried preparing the scene using the steps that you prescribed. Pretty mcuh the same result:




Am I doing something wrong or is this a bug?


Thanks,


Marcus

[RErender]

heh, dunno what you are doing wrong

Maybe upload your scene?

[RErender]

I remember one more thing I did, set the map size on the dome light to 1000 (the size of the hdri). I don't think it should make that much difference though.

[marcdevon]

heh, dunno what you are doing wrong

Maybe upload your scene?

This maybe something that I'll have to do. I wonder if I should report this as a bug though





Marcus

[marcdevon]

I remember one more thing I did, set the map size on the dome light to 1000 (the size of the hdri). I don't think it should make that much difference though.

Yep, tried that too.





Marcus

[DaForce]

Upload your scene and let us have a look.

Then we can tell if its a bug or not.

Also.. try a different HDRI.. even the kitchen one perhaps... here..

http://www.apex.net.au/~daforce/kitchen.hdr

[marcdevon]

Upload your scene and let us have a look.

Then we can tell if its a bug or not.

Also.. try a different HDRI.. even the kitchen one perhaps... here..

http://www.apex.net.au/~daforce/kitchen.hdr

Is there a way to upload my file to this forum? Otherwise, I''ll have to find a server, which I am willing to pay for, to upload my files to.



Marcus

[Paul Oblomov]

rapidshare.de up here....

[jacksc02]

do you have decay turned on? try turning it off