Thank you for your replies. It's most helpful. Perhaps I need to explain in a bit more detail. When I teach music I can draw on some 200 years of tradition. Teachers on my instrument have put in a lot of work over those year into what works didactically. When I say “this is a string and here are some ways to get a nice sound from it” I know what I'm doing. But with digital photography we seem have a lot of people floundering around, and much of the information is only “sort of” right.
For example, I don't usually use the term “raw image” as I doubt there is such a thing. If I can't see it and no one else can, I'd prefer to use the term “raw file”. The data is real, but the “pixels” aren't. My understanding is that most of us will not be able to find software to see the undemosaiced raw file. And my guess is that what I'm seeing on screen has also been rendered. Meaning I suppose converted to a jpeg or whatever and into a common colour space. In Lightroom the raw file will be in a form of prophoto rgb, but what am I seeing on screen? Is it a jpeg generated by the software to represent the file? I realised that I'm not even sure what I'm seeing when I look at an image on screen. It's like going to a concert of experimental music and not being told what I'm going to hear.
Most people with a digital camera are using it's software and hardware to convert the raw file into a jpeg, and are unaware that there is that intermediate step to produce their photos. When they join a camera society, it's an uphill battle to to get them to work with their raw files, and a lack of an accurate but simple way of describing what's happening doesn't help.
So I'm looking for descriptions of the fundamental processes in digital photography that are in simple words, and where I don't have to come back later and say “well that was only half right”
I may not necessarily want to teach this stuff, but I would like to accurately describe what I'm doing.
My beginning step has been to treat the raw data as information, and not as anything concrete. And then to call it an “image” or “photo” once it can be shared, meaning put into a common file format. I'm going to have to think some more about this.
As far as histograms go, what am I looking for in the lcd histogram on the camera.? I want to see how far to the right it goes to know something about the signal to noise ratio, and about highlight clipping. And I want to see how far to the left it goes to know something about my shadow clipping. I have a UniWb saved as a custom setting, and I can show someone what it looks like, but seldom use it as for most of what I do an approximation is good enough. Blue fungi are the exception. They are complete little b*st*rds as far as clipping in the blue channel goes.
Cheers, David
