Texturing For Extreme Zooms In
3dsmax By Neil Blevins Oct 17th 2007 Software: 3dsmax
This is a pretty common scenerio. You want to see something from far
away, then zoom in to get close, all in the same shot. Lets try this
the straight forward way. Lets say the shot involves seeing a city
sidewalk, then we zoom in to see a quarter sitting there. I have a 2k
by 2k image of concrete which looks fine at a distance...
Now we zoom in, and it looks horrible...
This is because we don't have enough resolution on the image. However,
to have enough resolution to look at the texture this close, we'd need
a 20k by 20k map. This is a huge image, your 3d software may not load
it, your ram may not be able to handle it, your camera won't photograph
something that big. Overall, it's a big mess.
So here's the trick. We're going to take advantage of the fact we're
only zooming into a specific area of the ground. Start with your
original image applied to a plane
Then take a photo of the concrete very close up
Place this image tiling 10 times across your plane in the u and v
direction...
Don't worry about the tiling you'll see from your far away distance,
just make sure you can't see the tiling when you're zoomed in. Now
create a mask that is white where you plan on zooming in, and black
everywhere else.
Place this into a mix map (in 3dsmax, but the theory holds for any
piece of 3d software, use a map that lets you blend between two
seperate maps with a mask). You get the following result...
And here's 4 frames of zooming in. Now you get a texture that holds up
for the close shot, and isn't unnaturally huge. (Note, adding
motionblur to the camera move not only adds realism, but also will help
hide the seam between your two maps.)
Also note, if doing an extreme, extreme zoom, you can also try placing
a second mix between an even closer image of the ground and your
original closer image. So you'd have 2 mixes, the first mixes between
your closer image & your even close image, and the second mix
between the result of the closer & even closer image and your
original image.
Here's the max file to show you the technique (note, the texture files
in this file are not 2k like I mention in the tutorial to save on disk
space. But the theory is the same) , max8: zoom_max.zip