Peer,
Good job on the tutorial. It's going to be very useful for the new users that have not been exposed yet to HDR images
Here is a little something for you that's going to make it easier for those that don't have a registered version with the QTVR options.
It's a Terragen script that will produce those 6 images in 1 click. So, you run it 3 times and only change the exposure in between.
I'm am pretty sure that the exposure can be changed by the script as well but I have not looked at that yet (I will then post a new version)
One way to use this script is to double click on it and it will lauch TG. You can then choose the location where to save the images and before running the script, change the image size, the level of details as well as the exposure.
For information, it takes about 3 hours to generate 6 images (900x900) at the max. level of detail and the highest accuracy for atmosphere and clouds.
Also, FYI, Terragen can generate also HDR images ( I will post later on this ) but then Pshop CS2 has to be used to merge those 6 images into a cross as there is no program on Mac that will do that or create a panorama. Too bad CubicConverter doesn't handle HDR images !