HDRI SUN

[rojerbb]

does the sun settings of sketchup works with hdri maps? how do i configure it?

[joe_b]

Re: HDRI SUN

The sky texture uses the sun information from Sketchup - it is an hdr texture. I'm not sure if that answers your question or not though

[rojerbb]

Re: HDRI SUN

more likely i was asking about my problem on why when i use a hdr, the shadows from the sketchup model doesnt appear when i render..

i ve been able to make it work only if i use the vray sky setting.

thats why i ask if with a HDR we are limited to not have the sketchup shadows?.

[dalomar_cg]

Re: HDRI SUN

Currently in order to have the sketchup shadows you must have the sky mapped for GI. We are looking into how to support the sun without the sky (this is possible with rhino and max).

[joe_b]

Re: HDRI SUN

Hmm - yes I made it so if you use the sun without the sky texture it just gets used as a regular direct light. It won't have the same brightness, but the direction of the sun is preserved.

[thomthom]

Re: HDRI SUN

Hmm - yes I made it so if you use the sun without the sky texture it just gets used as a regular direct light. It won't have the same brightness, but the direction of the sun is preserved.

I don't understand how you set this up. Can you explain?

[dalomar_cg]

Re: HDRI SUN

Have Default Lights on...don't have the sky mapped. You won't be able to edit the appearance of the light though

[thomthom]

Re: HDRI SUN

I've always had Default Light on as it's ticked in the default settings. However, when I set a HDRI as the GI skylight environment map there is no shadows. It all turns soft. Looks like it's just the HDRI in effect.

[dcauldwell_cg]

Re: HDRI SUN

This thread is very relevant for me at the moment.
I do a lot of photomatching, and sometimes the reference photograph is taken on a cloudy day (this is Britain!) so the shadows are very soft - but still present.
I have been fudging it (cheating) by using the physical sun and having strong shadows on my model, but recently decided to try HDR in the environment slot. I have some degree of success, but it is tricky getting a HDRI which has enough 'punch' with its hot spot to get a shadow at all. The shadow you get from the physical sun is much too harsh and defeats the object. This shot is the best I've got so far.



David

[thomthom]

Re: HDRI SUN

That's exactly what I'm doing as well. I prefer photos taken with some clouds as I find it's nice to have something to fill out the sky and it makes for a nicer colour balance avoiding too much glow and glare.
But I've yet to find an HDRI that actually produces any sense of directional shadows. Can you recommend any?

Is the image you posted lit by only HDRI?

[dcauldwell_cg]

Re: HDRI SUN

thomthom
Yes, this is only lit with a HDRI in the environment slot (default lights OFF)
I used 'cloudy_01-8k.hdr' (92MB !!) from spectralogue and rotated it 150 deg. I would really have liked more punch from the directional light, but it is near enough!

David

[thomthom]

Re: HDRI SUN

Have you had any experience with Hyperfocal's HDRI maps? They look interesting. http://hyperfocal.vismasters.com/cat...x?product=3611

[dcauldwell_cg]

Re: HDRI SUN

I haven't tried these, so I'll give them a go, Thanks

[thomthom]

Re: HDRI SUN

Could you post back your experience? I'm considering getting one of their packages for the office if they should prove promising.

[dalomar_cg]

Re: HDRI SUN

Well, It would seam that something is up, because there should still be the sharp shadows from the default light. Maybe there's something about not being connected to the sky that throws things off...I'll try and take a look today.

On the other side of the coin, you're going to be hard pressed to find an HDRI that will really give you shadows that rival any sort of lighting. Because of how HDRIs it just becomes really trouble some to have a texture that will generate distinct shadows. The other components to this, is that if you did have a texture that could do really well with those shadows, then there would probably be other kinds of reflection or glossiness artifacts within the scene. And for the icing on the cake, a texture thats going to generated decent shadows is going to take longer to sample. I'm sure that doesn't help, but maybe it explains it a little bit.