I use whatever is right to get the job done. What is 'right' depends entirely on the situation - the location, the subject, the intended use.

Back in the film days things were easy - I used an Olympus OM-4ti pretty much exclusively. Small, rugged, with a wonderful manual interface and huge viewfinder, it suited me perfectly. However the conveniences of digital have been impossible to ignore and it has been reluctantly retired. I've got more choice nowadays, and the capability to get shots I could only dream of previously, with the price being never having quite the unconscious connection with the camera I had before.

In the mountains I'm often severely limited on what I can carry. When going light and fast and seeking only to record my own adventures, I might only carry a compact - currently a Ricoh GX100 - chosen for image quality (RAW is a must) and manual controls. Given a little more space I'll take my main digital SLR body - currently a Nikon D300 - with a single lens that either offers the flexibility (currently a 16-85mm), or a prime lens with which I can create images with a consistent feel (usually a 35/2).

On outings where photography is the main objective I've got a cupboard full of lenses, flashes and other gear to choose from. For climbing and nature work the D300 is the workhorse, with a bunch of lenses from 12 to 300mm, including a couple of old Zuiko macro lenses on homemade adapters.

For landscapes I prefer to use film where possible, mainly using a Mamiya 645 with Fuji Velvia and prime lenses from 35 to 150mm. One reason is a bigger, cleaner viewfinder - not the kind of thing which is obvious on spec sheets but is a huge aid to cogent composition - another is simple manual controls. I find film still offers superior colours to digital when it really matters, such at the start and end of the day and for skies and vegetation, though as software and my skills improve the gap is narrowing. To add a little flexibility to my most used focal length for vistas (approx 28mm in 35mm terms) I've got a Hartblei 45mm Tilt and Shift lens. This offers the control over drawing and depth of field normally associated with large format, but in a far more compact package that can be deployed much quicker in the field. I find the slower speed of working on film, plus the expense and delay in reviewing each exposure, helps impose a discipline on work that aids more considered results.

For carrying gear I've got a selection of Lowepro bags - the most used are Vertex 200 for carrying the full works, and an Inverse 200 for going light.

Favourite bits of kit for climbing as well as photography are regularly discussed on my blog.