I am a police officer rather than a Scene of Crimes Officer, but can offer some help. Most of our SOCO's begin as Assistants in one form or another - they do not specialise in anything particularly, as their job is to recover evidence, preserve, record and photograph things. A fully-qualified SOCO will spend more time working on their own, or directing people at larger sites.
The actual photography itself is, as you might expect, purely functional. Our SOCOs use Nikon D40's with off-camera flash for most crime scenes, which are nothing like as interesting as you might imagine. Often, they're just location shots to give a court an idea of where an offence took place.
The most common offences where SOCOs are used are burglaries - not deaths. The average London borough has somewhere between 2 - 10 murders a year (some have none at all) and a few more deaths through traffic accidents, etc. I suppose some people are sensitive about it, but you don't need an especially strong stomach for the photography as such. Pathology - as some people are referring to above - is a different kettle of fish, but is nothing to do with a SOCO. Arkady's description of the usual conditions of work are accurate.
In the main, SOCOs are responsible for identifying initial forensic leads, evaluating them and then sending them off to a lab for further testing. It's not like on TV where the SOCO is responsible for investigating the scene, gathering evidence, then processing it back at a purpose-built lab at a police station.
Entry routes vary. Most SOCOs are university graduates, but their subjects weren't necessarily scientific.
This link is not for an Assistant SOCO's role, but it gives you an idea of one of the many roles available in the field:
http://www.metpolicecareers.co.uk/policestaff/evidence_recovery_technician.html
Pay will vary according to shifts and where you work, but in London an Assistant SOCO can expect a salary of around £25k - 30k, while a fully-fledged officer will take home quite a bit more.
suspect
