Rene:
It may seem kind of counterintuitive, but the book to use is one geared
toward basic film photography. There is no difference in the relationship
among ISO, shutter speed, aperture, and light between film and digital
media. Anyone who has a good handle on how these 4 variables interact has
the technical ability to create--and manipulate--properly exposed images,
regardless of the media used. The general book will go into things like
depth of field, lighting, lenses, motion, night photography, etc. and are
useful for learning the concepts of how a photograph is either made or
ruined.
Also, have your friend get a camera-specific "this button does this..." book
if the manual is printed in small, jargon-laced text which sounds like
someone used Babelfish to translate it through several languages before
stopping. But the basic guide to photography (Hedgecoe's guides are
favorites of mine) is really the best first step.
The artistic factor is another story, as previously discussed, and over
time, particular styles can be developed and fine-tuned to enhance the
process.
As for commenting, read lots of critiques and get the feel for how they are
presented. Then try it out. Those who submit critiques and those who submit
the photographs should be equally open-minded. Nobody seems to mind if you
write three words, a haiku (as some have done in the past), or an essay. By
listening to my own critiques of others' photos, I have learned a great deal
about my own shooting.
Generally, when I critique work, I start with the technical aspects and
address each individually. How is the overall exposure? The contrast? Are
there blown-out highlights or blobs of shadow? Do these add to the strength
of the image? How was the composition handled? What do you like about the
image? Follow that with: What would you have done differently?
Overall, I avoid taking into consideration the specific subject matter, as
that opens the door for very opinionated discussion which deviates from
talking about the quality of the image.
There are a few books out there about critiquing (or "criticizing")
photographs. I think I may have read one about 15 years ago...
Hope this helps!
Darin Heinz
Melbourne, Florida USA