NSGS AncestreeNebraska State Genealogical Society Journals
Volume One, no 2, pages 73-74
Fall 1978
A-Written by Kermit Karns, Kansas City Mo
MICROFILMING FOR THE GENEALOGIST There are a number of cases where genealogists wish to copy genealogical primary source material on a more or less wholesale basis. The purpose of such a project might be the preparation of a countywide genealogical index, or producing a copy of the records that can be used by a person to search at a distant location. Examples are: county marriage, school census, and death records; church baptismal, marriage, and death records; cemetery records, etc.
The obvious way to do this is through some sort of photographic means. While copying on a photocopying machine can be used in some cases, the sheer volume of copies becomes staggering. An obvious compromise is some sort of photographic approach. This can be done with a 35mm single lens reflex (SIR) camera or a commercial microfilm camera. But a person should be fairly well versed in photography before starting.
Thirty-five millimeter (35mm) SLR cameras together with a suitable closeup lens, tripod or copy stand, and two copy lights will provide satisfactory results and can be used in low volume projects involving a few hundred pages. One approach for a few dozen frames, would be to have the 35mm negatives processed into regular jumbo photos and use a magnifying glass to read the material. But the customary way would be to splice the negative film together to make up 100 foot rolls. It is not prudent to use the master negative film in a reader because of scratching hazards, although it can be done if no other use is planned for the film. It is customary to have a positive reading copy made and use that on the microfilm reader.
In order to obtain the optimum exposure for the film in text copy work, what is known as a 'step test' is conducted. A test length of the film is exposed to the desired copy under several different exposure settings. The film is then developed by a microfilm-processing lab and checked on an instrument called a densitometer for a background density of about 1.1. The exposure that gave this reading is then used to do the whole job. While the regular exposure meter on the camera can be used for the exposure setting and the results will be useable, they will usually be less than best.
Microfilm for 35mm cameras is only available on 100 foot spools so it must be reloaded onto regular 35mm camera cartridges. High contrast copy film on 36 exposure cartridges is available and suitable. Panatomic-X film will give readable results, too.
Filming with a 35mm camera is a rather tedious process. First, the film cartridges only contain a maximum of 36 exposures so they must be changed rather frequently. While film magazines of perhaps 250 exposures are available for a few 35mm cameras, they are expensive. Then the camera focus and framing must be checked each time the film is changed and every now and then when shooting. Also a glass plate called a flattening glass is usually needed to hold the pages down flat. In the cycling process of winding the film and cocking the camera, tripping the shutter, lifting the flattening glass, turning the page, and lowering the flattening glass, a person sometimes gets confused and either copies one page twice or misses one page entirely. It is helpful to have a second person assist so as to reduce the errors. A motor driven camera is helpful in this work as it eliminates the step of winding the film and cocking the (continued)
Nebraska Genealogical Society Vol. 1, No. 2. Page 74
B-Written by Karns, Kansas City Mo
(continued-Microfilming For The Genealogist)shutter, but it is expensive, too.
For higher volume work involving more than 1000 pages or so, it would be considerably more convenient to procure a regular commercial microfilm camera. This equipment has a shutter and motor driven film-advance controlled from a single button. Additionally, the film is used in 100 foot rolls. With a 16mm camera, this gives perhaps 2600 exposures, while with a 35mm outfit, it will give 600 or more exposures, depending upon the length of the framing. However, they are expensive, costing perhaps $1000 for a used 16mm camera and perhaps $4000 for a used 35mm outfit.
The commercial microfilm cameras usually have an automatic exposure motor arrangement, however, one must still go through a step test to obtain the best exposure for the work at hand. While the 35mm equipment has a large range of reductions and document sizes, the 16mm camera is usually limited to two reductionst such as 22X and 27X, and to two field sizes, such as 8 1/2 X 11" and 11 X 14". Due to the size limitations of the 16mm equipment, larger documents must be taken in two or more frames. While this is practical with single sheets, large books must usually be filmed in two sections, the top half first in a forward reading mode. Then the book is reversed and the bottom half filmed in a backward reading mode. After the negative is processed, the bottom half is cut out and respliced in so that it reads right side up and forward to back. While this is not really satisfactory from some viewpoints, it is satisfactory to a genealogist when he understands the problems involved.
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