September 13, 2009
Microfiche Jacketed Cards are the 4 inch by 6 inch index cards that contain frames of 16 or 35 mm film inserted into the jacket of the cards. These cards are a special type of microfiche cards. They are made of two layers of film in such a way that it allows for frames of microfilm to slide between the two layers. The strips of microfilm that are place into these slots are sometimes made up of separate and individual frames.
These frames are not secured in the slots and thus individual frames can slide sideways and may even overlap each other. When this happens, the frames would need to be moved back to their separate position. Sometimes, frames can slide and fall off of the cars. If care is not taken immediately, these frames can get lost.
In the process of digitizing microfilm jackets, is is important that the frames are not touching each other because the scanning system require some space between frames to separate the images from each other. This is referred to as image detection.
When jacket fiche cards are duplicated, the resulting duplicates look similar to the originals but they are no longer cards of jackets frames. Instead, they are a one piece of 4 by 6 film with pictures of the original frames embedded into the film. In these new duplicated cards, the images are fixed and thus they can no longer move out of position.
If the event that the duplicated cards require microfilm scanning, as stated before, the images need to have some separation to facilitate frame detection. So make sure that images are not overlapping, before duplicating the original microfiche jackets, is is important to make sure that the frames within the jackets have to moved out of position, and if they are, they should be move so that frames are not overlapping or touching.
Although images are scanable even if they are touching, a more time consuming and costly process may be required to separate the frames from each other.