Attached Link: HDRI render using Terragen hdr file

If any of you know Terragen, you'll know that it's an excellent program for producing realistic landscapes, AND it's free for non-commercial use. Now that C3 can cope with HDRI rendering I thought I'd experiment with Terragen, which can write to the HDR format if you install the (free) SOPack plugin. You need to follow a strict proceedure and there's an excellent tutorial, with links to all the (free) software you need here: http://www.cs.uh.edu/~somalley/helent.html However, there are a couple of things that you have to do differently for C3 when outputting the final HDR file from the HDRShop program. In the Panoramic Transform dialogue box, make sure the Destination Image selections are: Format: Latitude/Longitude (this gives the 2:1 rectangle which is all C3 can handle) Width: put the same number of pixels as your source image (the Vertical Cross one you've loaded) Height: this should be half the width in pixels Make sure 'Use Bilinear Interpolation' is unchecked Click OK an you should get a new 'warped' version of you source file. Before saving this you need to do one more thing. From the HDRShop 'Image' menu, choose 'Pixels' then 'Clamp at Current Exposure'. (If you don't do this then horrid white blobs will appear on any non-reflective surfaces in your C3 render.) Then save the file as HDR format. ** HDRShop will also save as ordinary bitmap or jpeg which you can load in C3 as a background or backdrop. And it will convert photos to panoramas so you could even make your own HDR maps with a digital camera. Sorry for the length - I hope someone finds this interesting! Mark

Same file coverted to bmp for background and backdrop skylight render

Bmp version of HDRShop hdr file

I found it interesting, thanks!!

Your images look great. I followed your instructions but I seem to be hitting a snag. When I use a Terragen created HDRI file (top), I don't get much illumination and the reflection looks dim and dull. The second image is using a HDRI file I downloaded and the exact same settings as the top render. Any suggestions? Did I miss something? Thanks.

I'm not sure what's going on here. I'm puzzled that the sphere and plane are so dark and yet the background so light. Have you tried roating the camera so that a different area of the map is shown? If there are large areas of shadow in the Terragen file it will obviously affect things. It may also be helpful to reduce or increase the brightness for Terragen maps, either in HDRShop or by using the Itensity slider in C3. Sorry not to be more help. I'm new to this too! Mark

I have tried rotating the camera but get the same result. The intensity of the Terragen HDRI image is already up to 200% - that's why it looks so bright. I can understand that it could be in a "shadow" area but the reflection should still be much brighter. Trial and error - must keep trying. Thanks for getting us this far.

I'm new to this HDRI stuff too, and have been trying to make HDRI images from my digital camera. I have found you need to make as many exposures as you can up and down by multiples of 3 stops on each exposure. Until the picture is blown out or black. Then combine them in HDRShop. You can even add a sun into one of the darker exposures to get harder lighting. You do need this range to light the 3D scene properly. Could the Terragen picture, altho it looks nice, not have the dynamic range of lighting to correctly light the scene and be a background as well. I have also found that HRRI images are useless as backgrounds, and should only be used as a light sources. I use another image in backdrop, usualy a digital photo taken in the opposite direction of the HDRI. I'll keep trying if you all will. PS Has nobody tried all the free HDRI images on the full Version 3 CD, or are you still waiting for it to arrive... He He

Still waiting. :( Haven't even received and shipping email from Eovia yet. I did order it on the last possible day though.

One tip I picked up from the HDRShop forum: after the program creates the image, hitting the plus and minus keys will cycle you through exposure levels. If it starts out looking too dark, 5 or 6 hits with the plus key will get the exposure to a more natural level. Then go to Image>Pixels>Scale to Current Exposure. My original images were coming out very dark at first, with the same results that you are getting: Dark and dull. This fixed the problem

Attached Link: http://www.benbus.co.uk/tmp/hdr_test.zip

The higher resolution the HDRI image the better it looks in the background. (One of the samples on the CD is pretty huge.)If you use a bmp version of the HDRI file as a backdrop as well as a HDRI background you tend to get a result similar to above - bright background and dark reflective surfaces. But I haven't played much with the settings. I've made up a zip file which includes Terragen files,HDR file and C3 file for the image above so that anybody interested can see what settings I used. It's available at the link and weighs in at about 1.5Mb. One note, I'm using Terragen version 0.9. I'll post a link shortly for the upgrade. Mark

Attached Link: http://www.planetside.co.uk/terragen/download.php?item=winup9

Install this on top of 0.8.68