Shutter bug

 I was asked an awkward question about chromogenic black-and-white film that I couldn't remember the answer to, because I haven't use the stuff for years. It's film that uses colour dye clouds, rather than clumps of silver, so the result is a film that can be processed in C41 colour chemistry and that lacks the grain of silver halide based film. This gives a smoother, sharper looking image which suits some people's taste.

In fact, I like the grain of silver film and think that it gives a pleasing image quality, with different film and processing chemical combinations giving different grain structure. This is one of those things that makes photography interesting. At one time I had a job printing the work of a photographer who sometimes used this chromogenic film, and as a printer I hated it because there was no grain to focus on. I remember describing it as 'gutless' film. And cursing in the dark.

So this is a typical example of photographic decision making - we learn about the science and structure of it, we consider the practicalities - in this case we can process at colour labs - and we consider the visual effect and whether it is desirable. And sometime we have a gut reaction, which is purely personal and subjective. Thus photography - scientific, technical, practical, aesthetic and personal.

I don't know if this answers the test question, but I found it interesting. 

Shutterbug is a handy site, where I was reminded about this film, and many other things I've forgotten about:

http://www.shutterbug.com/equipmentreviews/software_computers/0208whybrid/index1.html