What is a DEM?
Oops, sorry. DEM stands for Digital Elevation Model, and what it essentially is is a grayscale representation of a terrain’s surface and elevation; where the various shades of grays to white to blacks have been calibrated to a particular elevation. So, one shade of a lighter gray might stand for 20 m in elevation, another darker shade of gray might stand for 10 m in elevation, a darker shade again might stand for 5 m…etc., You get the drift.
White in the grayscale are usually the highest elevations, while blacks the lower. It’s similar to what Bryce is doing with their terrains, in that, when you create one, they are giving you a grayscale version. Only difference with the DEMs is that they are calibrated, that is, the colours (grays to white to blacks etc.,) all have been allocated specific elevation values according to the different shades. This is just the technical side to DEMs, however, I think they might still be what you’re after for use in creating simple lunar terrain that doesn’t require any specifics.
So in that case, they would be ideal for you, as you can still play around with reducing the elevations, or adding several DEMs together (if Bryce doesn’t crash in the process). The DEMs are all in 16-bit format, so they are ideal, because if you go any lower to, say, 8-bit, then they are useless; if you want to avoid ‘stepping’ effects.
Images below might give you an idea as to the power of DEMs (top is an example of a DEM, bottom two shows a Bryce terrain mat overlaid on it, each from different camera views. Here’s a link to the lunar DEMs (http://imbrium.mit.edu/BROWSE/LOLA_GDR/CYLINDRICAL.html).
Yes, quite correct, and there’s another option of creating a rounded Bryce terrain and adding it into the terrain. But, they still aren’t suitable, in my opinion.
Click thumbnail to see full-size image