What does this mean, am I using it when I take my photo`s or not. How can I tell. Only ever see these initials when I`m using photoshop but I have no idea what they mean or how they relate to my pic`s.

Vivienne, I checked the specs of the Olympus you are using, and yes, it can be set to shoot in RAW. You will find this option in the menu.

RAW means nothing in particular. It is the file format to which the camera does the least processing. Contrary to popular belief, RAW files do undergo some camera processing and systematically require post-processing.

Olympus camera RAW files end in .orf. Nikon files (I think) end in .nef. The Canon RAW file extension is .cr2. Your camera's LCD or top panel (if it has one) will tell you whether you shoot in RAW, jpg or both at the same time. The option is usually found in the "Image quality" menu.

The simple answer to Vivienne's question is this: if you're uploading images to PB without having to convert them or save them as a jpg, you're shooting in jpg.

Digital cameras, especially those with cropped sensors, apply a lot of sharpening, colour correction and other editing operations to analog data captured by the sensor and converted to jpg, which also includes significant data compression. The data in RAW captures remain almost unprocessed and uncompressed, which makes them much larger. Think of RAW files as digital negatives. The problem is that RAW file formats are proprietary, i.e., you can't read an Oly orf file without Olympus software. Adobe has tried to create an industry standard RAW format (.dng), which only Leica and digital medium format cameras use at present. You do have the option to save as a dng file in ACR, the RAW processing utility shipped with Photoshop.

RAW advantages: much easier to correct exposure; far greater level of information detail, which means image editing operations are less "lossy" (you don't lose information so much).

RAW drawbacks: RAW files are 2-3 times larger and require more buffer (i.e., in burst mode, you get fewer images before the camera chokes - sports photographers still shoot almost exclusively in jpg). All RAW files must be edited (you must correct for midtones at least).

When to use RAW/JPG: many cameras allow you to store both simultaneously, but this slows down your burst speed and fills up your card very quickly. My rule-of-thumb is as follows: if my subject is immobile (composed portraits, flowers, landscapes, buildings, etc.), I shoot in RAW. If my subject is mobile (children and other wild animals, ha, ha), I shoot in jpg. One exception: difficult lighting. In low and/or contrasting light (concerts, interiors, etc.), shoot in RAW.

I hope this helps.

Great, mean to try this out, but is it better. I often do very little other than crop. Could be good for photographing my prints and pots etc those i do have probs with colour change etc. viv

"Colour change" may refer to the darkening - "dumbing down" of the colour spaces used off the web when converted to sRGB ("stupid" RGB) for the web. See my article in the digital photography section of the forums on colour spaces.