The Making Of The Simulation Of The July 13, 1959 Blenheim NZ UFO Sighting

"Still Life With Plants" was the first complete work I created with the Aladdin program. This image is the second.

There are many constraints on the artist who is choosing to recreate an actual event. Under normal circumstances, an artist is concerned primarily with the aesthetic impact of the resulting image, while subject, composition, and color are all at the service of this imperative. In the case of a historical recreation, the artist is constrained by documentary descriptions of the event, and yet must manage to create a realistic and compelling representation.

This sighting is particularly well suited to digital recreation. The incident is clearly described by the primary witness, measurements were made by the investigators, and detailed drawings of the object, including dimensions, are part of the file.

An initial objective was to make the image as realistic as possible. This meant using extensive photo support for the background and foreground, while carefully managing the unusual characteristics of the UFO in such a way as to both demonstrate the unusual appearance as described by the witness, and yet convey a sense of the reality of the event. This meant careful use of textures, lighting, and transparency. In fact, this rendering uses

• Multiple light sources
• Nested glowing semi-transparent objects
• Flares
• Reflection maps
• Background texture
• Quadratic primitives
• Lathed shapes
• Grouping, group duplication, and group rotation
• Image processing on several images

The project was completed within about two working days. It used Aladdin, Image FX, and TVPaint Jr. The Aladdin representation of the UFO comprised 12,000 polys, most of which were needed for the luminous "jets" around the rim of the object.

The first stop was my extensive personal photo library, searching for the right landscape. July is a pretty cold month in New Zealand, and the conditions on the day in question were overcast, at dawn light. The setting is a farm paddock - a field, surrounded by trees, mostly pines. Naturally enough, no single picture met all of the conditions.

I began with a good photo of a field. Or, it would have been a good photo - except that it was taken on a blazingly sunny day with a crisp, clear blue sky. I also had an excellent foreground tree - except that its background was a field too crowded with trees to work with the composition I had in mind. And I had an excellent overcast sky - except that it had been taken from the top of a 4000 foot mountain in New Hampshire, and clearly showed its altitude.

I decided to put the right parts of each picture together into a background that would meet my requirements. In Image FX, I started with the image of the field, lowering contrast, saturation, and brightness until it attained the appearance it would have under an overcast sky near dawn. Next, I cropped the sky, scaled it, and used "rub through" with filled rectangle and polygon tools to bring it into the field image, replacing the original sky.

Next I had to decide how to deal with the foreground tree. I had two alternatives. One was to create an Aladdin "genlock" foreground texture with the tree against a black background. This would leave the area around the tree clear so that it could be looked past into the landscape. The advantage would be that the object could then be partly obscured by the edge of the tree. However, because the blending of genlocked objects is not as good as what could be attained with image processing, and because I did not envision needing the tree to be in front of any part of the object, I simply used rub-through to merge the images.

Finally, I applied some smoothing to the edges of each of the components to help make them an organic whole.

The next stage was to create the UFO in Aladdin. This turned out to require a fair amount of experimentation.

First, I created the core of the object from a quadratic ellipsoid 4/2. Then I lathed a rectangle whose diameter was slightly larger than the ellipsoid, to make the upper rim. This was then cloned and moved down to form the lower rim.

The primary characteristic of the object was its luminous jets - with green cores and orange around the core. Initially, I tried working with gases. Finally, I decided I didn't understand gases well enough, and I was not developing the look I wanted.

Next I tried working with transparent objects. I made a cone by first creating a three point arc and then lathing it. I used 12 sections, which was probably too many. Then I cloned the cone (ha ha) and shrank it to fit within the outer cone in the rough proportions shown for the green center vs the orange outer part of the jet.

Then came a time-consuming set of experiments with the color and transparency of the jet core and sheath. First I set glow to 255. Then I started experimenting with the color. The problem lay in the filtering of the inner green by the outer orange. I could get a good orange and the green would be too yellowish. Finally I found what I thought was a good combination. But then, when I put it in front of a whitish surface, it was wrong, and I had to tune it some more. I did this by making sure that half of the cone pair had the white surface behind it, and that the other half didn't. That way, I avoided tuning against white and losing the proper appearance against darker colors. The final result seemed good enough to start the task of spreading them around the rim of the object.

At first, you might think this a difficult problem. After all, there are a lot of these jets - on the order of 80. But the ability to duplicate and rotate groups makes the job a lot easier.

The next part was done from a z-axis view, orthogonal.

First I grouped the original jet and cloned it. Then I placed the clone on one side of the object. I cloned it, and then rotated it 90 degrees, and placed it on the other side of the object. I grouped the two, cloned them, and rotated the two by 90 degrees. Then I grouped the four, cloned them, and rotated the new four by 45 degrees. Next I grouped all eight, cloned the group, rotated it by 22.5 degrees. I kept repeating these steps, halving the rotation each time, until the ring was complete. Then I grouped the ring, cloned it, switched to a side view, and shifted the cloned ring to the lower part of the object.

Now it was time to deal with the cockpit and the occupants. The cockpit was a simple 4/2 quadratic ellipsoid, which was rotated 90 degrees scaled smaller in the z direction, and then sliced in half. I then set its attributes to nearly transparent grey.

I spent a significant amount of time trying to cut an opening for the cockpit with LOSCut. Unfortunately, I could not get it to work, so, instead, I created a shallow rectangular solid, which I made completely non-reflective and black and placed under the canopy. Next, the occupants. Based on the sketch, I only needed shoulders and helmet. A 4/2 quadratic ellipsoid, scaled narrow on the x-axis, and a 1/2 quadratic ellipsoid, scaled similarly, made the shoulders and helmet. Grouped and then cloned, I now had two occupants.

The report also mentioned a flashing light inside the cockpit. I used a light and a flare; the light provided the correct lighting for the occupants, and the flare simulated a light source.

To complete the object, I phong shaded the main body and spherically reflection mapped it from a version of the background which omitted the foreground tree. The scaling and sensitivity parameters were all set to 1.

There was one area which was a disappointment. While I had solved the flame problem, the bright green lights on the bottom remained unsolved. The lights would cast a cone with a notable falloff in intensity. I spent some time experimenting with procedural and bitmap opacity textures on cylinders and just didn't attain the results I had wanted. Finally, I gave up, and brought the images into TVPaint Picasso Jr, where I used gradient fills to create the appearance of bright green beams from the bottom and light pools on the ground.

The result was what I had hoped. At least until I tested it in the Netscape browser. Unfortunately, the dithering obliterated some of the detail when seen with 256 colors. Therefore, I spent some time with compression and lightening until the dither effects were minimized. But, not completely satisfied, I generated a second, closeup rendering. I wanted that rendering to look as much as possible like a closeup of the first rendering. So I brought the rendered image and the background into ImageFX. I then was able to use the light table to estimate the area that would be occupied by the next rendering. I cropped the resulting area of the background, expanded it to a full frame size, and saved it. In the new rendering, I zoomed in to the object and used the new background, which gave me a good closeup. I had to repeat the painting to recreate the green light from the underside, but once that was complete, the work was done.

Aladdin is a fascinating program with capabilities in still imaging which this work only begins to explore, not to mention advanced animation capabilities which will be the subject of future work. If you are an Amiga owner, visit the Nova Design website for more information.