Exterior HDRI panoramas with Bryce?

Singular3D

I looked around, but didn't find anything so far. Been in this topic some years ago and try to get back. Had some discussions about that with @DavidBrinnen and @Horo a while ago.

At the moment I'm using Cinema 4D with Vray. For outdoor renders you need a good HDRI panorama. I have a nice collection of HDRIs, but sometimes you need HDRIs for fantasy or Sci-Fi scenes. These have to be created with great landscaping software and Bryce, as well as Carrara can certainly deliver great results. My goal in the first place are HDRI skies, but also complete landscapes.

Now I just wonder, if there are any tutorials on how to get such HDRIs (up to 32bit) out of Bryce or Carrara. I'd love to adress this topic. Are there any generated high quality HDRI sets available?

Thanks in advance.

Horo

You can save a Bryce render as 96-bit TIFF or Radiance HDR file. However, Bryce renders 48-bit only and the renders saved as HDRI are not truly HDRI but at least gamma is removed. Making an HDRI from a render is a bit tricky but can be done. The scene has to be rendered several times under different light to emulate f-stop (or exposure time) changes. Then, the renders can be merged to an HDRI. Another problem is that you need a spherical panorama. There is the Spherical Mapper for Bryce (commercial product available here at Daz 3D) but the maximum width for a Bryce render is 4000 px so the pano gets 4000 x 2000 px at best. The 4000 px limit is only horizontal. I never tried it myself but rotating the camera by 90 degrees should be possible to render vertical 8000 and horizontal 4000 px and then rotate the render back. Otherwise, parts of the pano must be rendered and then stitched together. With Bryce come 4 tutorials how a HDRI pano can be made (faked) in Bryce: (wherever Bryce is installed) > Content > Tutorials > Horo Wernli. The tutes are a bit old but still give a good overview.

Generally, you have to master two different parts: (a) creating a spherical panorama big enough to suit the document size and camera FOV of the final render in which it is used as backdrop; (b) creating several renders differently lit to fake multiple exposures of a camera. I made a couple of (fake) HDRIs (indoor and outdoor) from Bryce renders. It's a laborous undertaking and my results were between Delete-Immediately to Not-Too-Bad.

Singular3D

Thanks for your fast reply. Wasn't aware about the 4000px limit.

I remember doing renders with multiple exposures in the past and stitching them together with Photomatix. I also used HDRShop for converting HDRs from boxed to spherical.You can get great landscapes with Bryce, so I thought about going that route. When I use 6 renders (boxed) I could get Spherical images with higher resolution.

Carrara would be another option.

Well, I hoped that someone made a recipe to follow up. Seems I have to dig into this topic again, but I will schedule this to September. If you are interested, I'll share my progress here.

Horo

Thank you for reporting back, Singular3D. Technically, you can render wider than 4000 px in Bryce if you render to disk. This is no option for me because (a) only 1 processor is used and not all (up to 8) available and (b) Bryce has an affinity to crash. If you render boxed (I call it the 6 faces if a cube), set the camera FOV to 112.5 with Scale 100. There is so much to tell about panos and HDRI that it is difficult to put it in a nutshell and there is no single recipe but several. I would appreciate if you share your progress. Also, do not hesitate to ask specific questions, those are usually easier to answer.

Singular3D

So my dual Xeon (6-cores) won't help here. 

I'll keep you posted about my progress, although I may start not before September.

mindsong

watching this too, thanks (and thanks horo for your extensive docs on this). didn't think about rotating sideways... hmmm.

cheers,

--ms

c-ram

There's a way to render larger than 4000 pixs : rotate the camera 90° left or right and modify the field of view to adjust its position.

 

This has given me the possibility to render the picture above in 7200 per 2000 pixs. But with this trick you could render wider and in this case, I'll have the opportunity to render at the incredible size of 14400 per 4000 pixs wich is quite confortable.

Horo

For spherical panoramas with the Spherical Mapper rotating the camera won't give you the result you're looking for. I tried it yesterday but could have thought it wouldn't work. Reason: you need to render as a 360 degree panorama. Turning the camera only works for perspective projection.