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Tutorial
Making QTVR movies
(In Lightwave 9+ and
Vue 5)
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What is a QTVR?
This stands for QuickTime Virtual Reality - it's basically one of those
small movies which provides a view that you can pan around, and zoom in
and out. They are not animated, but you can change the direction you
are looking in. You will need an up to date version of QuickTime (get it HERE) to view them - here is a sample. Click on the image below to start downloading it.
These can be rather fun, so I thought I would write a tutorial on how
to make them, using either Vue or Lightwave to make the raw images.
The basics:
You need to make an image with a field of view that is 360 degrees
around, and 180 degrees high - an equirectangular image. The top of the
image corresponds top the point directly overhead stretched out into a
line, and the bottom is the point directly below. The horizon line
should run directly across the middle of the image.
It should be twice as wide as it is high, e.g. 2000 pixels wide by 1000
pixels tall. This is then fed into a piece of software that will make
the QTVR. It is important to note that you need a very large image if
the results are going to look good. For example - consider an
image that is 4000x2000 pixels. With a 45 degree field of view that's
just 500 pixels across! For this reason I recommend that you work with
an image at least 3000x1500 pixels in size - though smaller ones are
very useful for testing.
Be careful when positioning the camera - in order to keep the horizon
level and straight, it is important not to tilt the camera, so no pitch
or roll. (The process will still work with a tilted
horizon, but it will look odd). Because the point directly under the
camera is stretched out, it's a good idea to avoid placing the camera
directly over something that is slow to render, such as
realistic water.
If the camera is not level, you will get a curved horizon line, that waves up and down.
I would STRONGLY recommend
turning off Lens Flares, and any other similar effects. These will look
very bad in the final image for 2 main reasons:
-
The viewer expects them to move relative to the light source / camera, and they don't
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They are drawn over the images as perfect circles, and will distort when converted to a QTVR.
You might get away with a small Lens Flare, but in general they are
best avoided for this type of work. Certainly avoid rings and strong
rays.
Also remember that by default, the centre of the image will be the
starting point for the QTVR, so set the camera heading to show
something interesting!
Camera settings in Lightwave:
In order to make an equirectangular image in Lightwave you need to use
version 9.0 at least, and the advanced camera. There is a sample scene
in the project files, and also a suitable camera preset. Here is a
screenshot of the advanced camera settings:
Camera settings in Vue:
Things are a bit simpler in Vue, and you just need to set the panoramic options on, and the field of view to 360x180, like this:
I am using Vue 5 Infinite, I am not sure which other versions have
these options. Again I have provided a simple scene for you. (As all
project files are small, I have just made one ZIP archive, available at
the end of this article).
Of course, you can also use any other graphics software that can produce equirectangular images.
Here's a small example of the type of thing you should get out:
So you should now have a properly mapped image.
Making the QTVR:
I recommend a nice bit of software called PANOCUBE. The basic version of this is free, and you can download it here:
http://www.panoshow.com/panocube.htm
There is also an advanced version, for an astonishingly reasonable $13,
with a lot more features. But start with the basic one and see how you
get on.
Panocube needs to use another piece of freely downloadable software, PTStitcher. Get that here:
http://www.tawbaware.com/maxlyons/pano12ml.htm
I won't go into the guts of the installation - (see the docs with the
program for that), but for the version I got, it was all pretty simple
- just unzip the files and place them in a folder. Before you can use
Panocube, you need to tell it where PTStitcher is located - do this by
dragging and dropping the PTStitcher program onto the Panocube program.
Warning!
One thing you do need to look out for! On windows you must NOT have a
space in the path to the Panocube files, the PTStitcher files, or the
Image Files you are using! As the most obvious places to put the
programs is in the "program files" folder, and the images in "my
documents", you are VERY likely to hit this problem! I created a folder
called C:\panocube, and
another C:\ptstitcher, and move my input images to the Panocube folder before processing.
Once you have this sorted, it should be very straightforward.
Using Panocube:
This could hardly be easier. All you need to do is drag and drop your
equirectangular image onto the panocube icon. It will chug away for
about a minute, and then you will find it has created an IMAGE.MOV file
(where image is the name of your image file), and IMAGE.HTML, a sample
web page with your QTVR in it. That's pretty much it! Double click
either output file to see what you have built.
Memory issues:
Making big images can leave very little free memory - if you find that
Panocube has not produce a .MOV file, but left 6 new images behind,
this is the probable cause. Close some programs to free memory, and try
again.
Tuning Panocube:
Panocube has a config file, which you can edit if you want to change
the default options. I have included the one I use most often in the
project archives. The key things I changed were:
1. Increased the size of the viewing window, to get a larger movie.
2. Reduced compression, for higher quality output.
I have put together the following files to help get you started:
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Sample very basic Vue scene with camera settings.
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Sample very basic Lightwave Scene with correct advanced camera setting.
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Advanced cameras preset for Lightwave.
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My Panocube config file.
Download the collection of sample files as a ZIP here.
You will find my gallery of QTVR's here.
My
downloads page
Which contains quite a few Lightwave objects and scenes
for you.
My
Galleries
page
Which contains quite a few Lightwave space and science
fiction images - look
under GRAPHICS
for these.