Article by George Michael - In 1956 we took delivery of some 704s from IBM on one of which there was a cathode ray tube that was imaged by a camera. It was called the Model 740. So, this was the Model 740 on the IBM 704. And there was also a direct-view tube that went with it, the Model 780—a modified television set. And one could look at the results as they were being played out at the same time that the objects were being plotted by the 740 and recorded on film. The difference in speed between the 'Benson Lehner plotter' and the IBM 740/780 was so dramatic that it quickly became the favorite way to produce graphical output from the design calculations. Of course, there's no free lunch. As delivered, the 740 was loaded with inadequacies.

		The unit while faster than anything else we had, was impressively slow, the distance between frames was not constant, the lens and the film used did not match the phosphor, a single frame advance took on the order of half a second. Initially, we were treated to the slow production of poor quality pictures. However, fixing these problems turned out to be easy, and it was stimulating and gave us the nerve to go to bigger and better things. Even including these discussions, not all the graphics work that went on at the Lab is going to be covered. The ones that are mentioned are intended to highlight some particular aspect of the graphical work that went on. In the abstract, the early display devices were ones that supply some hardware solutions for elementary actions like: Set the beam to the point (X,Y), Move the beam to the point (X, Y), Change the intensity of the beam, Move the film.
The IBM 704 computer room at Lawrence Livermore, Oc 1956.

With such primitives, it is necessary to develop programs that can display characters, draw lines and, generally, produce pictures that satisfy some set of requirements. The early display devices were delivered without such software; a situation that was both awkward and liberating. One might say that, instead of delivering, manufacturers abandoned their hardware at our door, and it became both our job and our pleasure to write the software—it didn't have that name then—that we actually got to use.

One of the most interesting pieces of software developed very early was a subroutine called "Plotla" written by Norman Hardy. Its only function was that between any two points in the lattice, it could plot a "best straight" line represented by a series of points that were spaced either every point, every other point, every fourth point, and so on. It was a very tight and fast routine. The speed of the 740 was such that it could only plot, in 151 microseconds, either a point at some location (X,Y) in a raster of 1024 by 1024 points, or starting at a given point, it could draw either a horizontal line, a vertical line, or a 45-degree diagonal line going from lower left to upper right from that given point. With that capability, one had to see all of things that you'd like to plot in terms of those three or four simple little capabilities. Norman's routine, even though there was some nontrivial amount of calculation being done to get the points, was a tight routine. Being as fast as possible, Plotla was used extensively. So, everything, practically speaking, was built out of that and one other subroutine. We used some data tables to design characters that could be plotted in a 5 by 7 matrix of points. With this capability, we were able to build routines that simulated all kinds of graph paper and plotted all kinds of points, and also, of course, with some trickery, produced strange kinds of surface texturing features. So an area could be textured or otherwise marked according to some prescription.
		Just on the right of the console, is the IBM 780 direct-view display and in the background, can be seen the Beattie-Coleman friction driven camera mounted on the IBM 740. Photo Lawrence Livermore National Laboratory (1956).

		The use of motion pictures in science was common enough, but it seems that no one had yet thought of them as being useful when doing mathematics and physics with a computer model. But there it was—a powerful new way to perceive one's results. So, several of us began looking into the uses of computer generated motion sequences. In general, however, computer time was too valuable to use it making movies. So, the movie-making mechanisms had to be careful not to use too much computer time and, certainly, to never waste time. Among other things, this inspired efforts to develop things away from the big computers, and a search for a small computer that could be used for movie making. One other approach was followed—the movie making capability on the big computers was improved.
The IBM model 780 display unit setup.

One of the first things we decided was that the camera was not acceptable for movie making and had to be replaced. At this point enters our Technical Photography Division. Then, Bill Jordan was in charge of it, but the guys who did the work included Dave Dixon and perhaps one or two others that I don't remember now. But what they did was to interface a real movie camera to the computer. The camera had pin registration and a claw pull-down, so that the amount of film that was moved at each frame advance was very, very accurately controlled to within a few ten-thousandths of an inch. And with that camera, we started producing motion pictures. The next problem that showed up was that the film being used was not acceptable. It had, in one case, a bluish cast, and the images were very blurry. I started dealing with some representatives from Kodak, complaining about the need for a much better film. They started bringing out samples of new coatings that would respond better to the kind of phosphor that was on the 5-inch tube in the Model 740. It was an exciting, interesting thing to do, to learn how to match the capabilities of the lenses, and the film, and the film processing, and the phosphor in the tube, and the amount of energy that was being produced by the unblanked signal, and so forth, and get that all to work together harmoniously, so that we got sharper images. But we did it. I should add that some of these developments found their way into a neat Kodak handbook on CRT photography, and some very excellent films were developed, giving more resolution and more photographic speed.

It was a tremendous amount of fun, but not being satisfied with just that, the next thing that people started talking about was, wouldn't it be neat if we could produce color pictures? By color-coding the data in each frame, one could see very quickly lots of new information that was not so obvious from looking at numbers or even monochrome pictures. This was, I would say, in the middle to the latter half of 1957.