Markings on negative

[Compaq]

Every time someone has a problem with the development of films, they get the question if the markings are visible (*).

Can some please tell what the deal with these are? Why is (*) such a key question?

Anders

 

[Helen B]

Because if you can see the markings, some development has occurred.

no image, no markings: probably no development, maybe a bleaching problem, either way a chemical problem most likely

no image, but markings visible: probably an exposure problem

 

[amolitor]

To expand on what Helen said, the markings are placed by the manufacturer on the film by exposing the edge of the film in the appropriate pattern. They're actually not visible on undeveloped film. Development brings them out. This is a design feature, and quite a clever one!

 

[timor]

The markings also include frame numbers, what is convenient with cataloging, especially if someone does bracketing. However not all films have any markings, some generic brands like Arista Edu 100 (my experience is with bulk roll) and if I remember Legacy Pro 100 (but this is gone now). Maybe out there is more.

 

[BlackSheep]

Also, looking at the markings can be useful for checking more subtle problems, such as if the film was over or under-exposed in the camera, vs over/under developed during processing. This website shows some good examples for trouble-shooting negs:
colour negs - Olympus Microscopy Resource Center | Photomicrography - Color Negative Film Processing Errors
and B&W negs - Olympus Microscopy Resource Center | Photomicrography - Black & White Film Processing Errors