Student-produced instructional films - ACS Publications

The acceptance of short movies as useful aids in demonstrating chemical principles or laboratory technique is apparently becoming widespread, as evi-...
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LeRoy A. McGrew Boll State University Muncie, Indiana 47306

Student-Produced Instructional Films

T h e acceptance of short movies as useful aids in demonstrating chemical principles or laboratory technique is apparently becoming widespread, as evidenced by the increasing commercial availability of such films. However, the lack of uniformity of apparatus and procedures in the laboratory programs of various colleges and universities may limit the applicability of commercially available films. The excellent ACa publication "Teacher-Produced Instructional Films in Chemistry," by O'Connor and Slabaugh, describes in detail procedures which instructors may follow in making films a t the local level. I wish to describe here an approach to the problem of obtaining locally applicable footage which involves students, is quite economical, and which requires a minimum of an instructor's time. Organic chemistry for non-majors a t Ball State University is a three-quarter course normally offered in a fall-winter-spring sequence. At the beginning of the winter quarter in 1969 I found myself teaching a section of the first term of the course being given out of the normal sequence. Half of the students present had been enrolled in the course before, had dropped out because of poor performance or failure, and were now trying again. Nine of these students had completed most of the laboratory exercises of the course during the immediately previous term. To these students I offered the choice of repeating the laboratory exercises, or of trying their hand at producing some short films which would he applicable to the laboratory. All nine elected the latter option with some enthusiasm. An organizational meeting was held a t which the students agreed on the topics to be filmed. The topics were to be limited to the first term of the course, and to the illustration of locally available apparatus. The following were chosen: 1) Melting Point Technique, 2) Purification by Crystallization, 3) Extraction Technique, 4) General Use of Standard-Taper Glassware Kits, and 5) Simple and Fractional Distillation. A director was appointed, an actor was chosen, two students agreed to learn proper camera operation, and two students were made responsible for titles and equipment. The director and two others agreed to plan sequences of scenes for each topic and to advise on the days of shooting so as to insure continuity in the finished product. I agreed to supply the necessary photographic equipment and to give advice only when necessary to insure the illustration of good laboratory technique. BARNARD, W. ROBERT, J. CHEM.EDUC., 45, 136 (1968). ASA 200, packaged and processed by Western Cine, 312 So. Pervl St., Denver, Colorado 80209. Thie film is available in many camera stores, or may be obtained direct from Western Cine. Processed film is usually returned within one week.

Photographic Equipment

Economy in the project required the use of 8 mm photographic equipment. There are essentially two formats available to the amateur in this gauge, and their dimensional characteristics and notes on their projection have been listed by Barnard.' The newer format, called super-8, has a 50% larger frame size than the older regular-8 format. Super-8 also offers the distinct advantage of cartridge loading. The regular-8 format was chosen for this project, however, because equipment happened to be readily available and because this format was judged to be adequate for the intended uses of the resulting films. Although super-8 has entirely replaced regular-8 from the camera manufacturer's standpoint, the older format has some advantages when it is used in this kind of project. Some very reasonably-priced new cameras are still available in many localities and good used equipment goes for a song. Projection of regular-8 film offers no problems, since many new projectors are designed to handle both formats. The cosc of film and processing is generally lower than for super-8 and the availability of Tri-X,$ a fast black and white film, in this format makes auxiliary lighting unnecessary in a room that is brightly lighted by fluorescents. This feature was quite important to this project because it was desirable to keep the filming technique as simple as possible. Color was judged to be unnecessary for the illustration of the chosen topics. The followinglist itemizes the cost of equipment and materials used in producing the films. 1. One Bell and Howell Model 134 turret camera, used. . . . . . . . . . . . . . . . . . . . . . . . . . $15.00 . 2. One tripod, new. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20.00 3. One light meter, new.. . . . . . . . . . . . . . . . . . . . . . . . . . .18.00 4. Seven 60-ft rolls~-Tri-X film. ~~-~~~ including processing. . . . . . . . . . . . . . . . . . . . . . . . . . 31.85 5. One regular4 movie editor, new.. . . . . . . . . . . . . . . . . 13.00 6. One wet splicer, for editing, new. . . . . . . . . . . . . . . . . 6.00 ~

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Total cost

$103.85

The camera, purchased by the author in a camera store, is now about 15 years old. It is equipped with a 12.5 mm normal lens and a very fine 36 mm telephoto lens which has proved to be very useful in producing the sharp closeups which are necessary in an educational film. The low cost of the camera should be duplicable in most localities. I t is the author's experience to find that the older-model Bolex and Bell and Howell cameras are of high quality and those that still work do a very good job of taking movies. Shooting the Film

A lecture room with a suitable demonstration bench served as the set. All shooting was carried out by the Volume 47, Number 1 1, November 1970

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students during the regularly-scheduled laboratory periods. About an hour was required to instruct the camermen in proper camera operation, since they bad no previous movie experience. The cameramen were instructed to keep their shots "tight," showing only what was necessary to illustrate the technique, and above all to insure the proper exposure setting and sharp focus. All shooting was done from a tripod mount and exposure readings were taken prior to each new scene. No auxiliary lighting was used and no special backgrounds were necessary. Titles were printed on small cards with a felt-tipped pen. Under these conditions, the director, actor, and camera crew were left to the task of completing the films with little intrusion by the author. During the shooting of a particular topic, the students not directly involved in the shooting planned the sequence of scenes and titles for the next film. The group worked well together with everyone making useful suggestions, and i t was not necessary to maintain a rigid separation of responsibilities. Shooting the footage to illustrate the five topics mentioned above required six 2-hr laboratory periods. During the seventh period the entire group previewed the processed film. At that time, as was expected, it was found that a certain percentage of the film was improperly exposed or in poor focus, and that certain desirable scenes had been left out. A list of scenes to be retaken or added was then prepared, and it was a t this point that the author exerted considerable influence. The retakes were accomplished during the remaining two laboratory periods and the author spent several evenings near the end of the term editing the film into final form. A total of 350 ft of film had been exposed. Results

All of the final films, while not of professional quality, are certainly usable for prelaboratory instruction. Two of them are quite good. Their quality, in terms of brightness and clarity, compares well with that of the commercial single-concept super-8 films. Anyone using a camera equipped with a good telephoto lens should be able to obtain similar good results, if on projection a screen image of about 3 X 4 ft is maintained, and the

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audience is seated in the range of 3-8 image widths. This image size is equivalent to a 60 in. TV screen and is entirely adequate for laboratory sections of thirty students or less. Of course, the projection room should be as dark as possible. The film maker's most prevalent error appears in the final footage in the form of several "jump-cuts." A jump-cut occurs when a new scene is presented without cbanging the lens or camera position used for the previous scene. It results in a somewhat "jerky" appearance of the projected film. This error, which may sometimes be corrected by careful editing, is most easily avoided when the film is exposed simply by cbanging camera position, or by switching from normal to telephoto lens, for each new scene. The five films produced in this project amount to a total running time of 23 min 18 see, which computes to an average cost of $446/min. Note that this figure is based on the total cost of the project which included the cost of the camera and other hardvare. The students thus proved to my satisfaction that educational movie making need not be difficult or expensive, but that it does require time, patience, and attention to detail. Of considerably more value is that the presentation of a different and challenging project appeared to stimulate these students who had previously done poorly in the course to do a better job in organic chemistry. The film group's average percentage lecture grade of 66.5 compares well with the average grade of 68.0 achieved by the other 18 students in the course. No one in the film group was judged to have failed, a rare situation in my experience with second-timers. Observation of the group in action made it clear that the students were required to know more about a particular technique in order to film it than they would have had to know merely to perform the operation in the laboratory. These factors alone would have made the project a success, even if no usable footage had been produced, and I intend to offer this kind of project again when the opportunity presents itself. Acknowledgment

The author would like to thank the Ball State Research Committee for partial financial support of this project.