iPhoto and unknown RAW Formats
A lot of cameras come with software to convert their RAW files to other formats. If your's comes with conversion then see if it supports regular TIFF. 

You might want to look into GIMP, which is a graphic program from the *nix world that runs under X11 on the Macintosh. It's very similar to Photoshop but is free. It has some auto conversion capability and/or might be able to read your camera's RAW files. GraphicConverter might be another option. It's got a long list of formats it supports and converts between.

Converting to JPG changes the file format in ways that make it a lot less flexible. I have my own photography company, and only shoot RAW when I'm doing serious work, because I need the flexibility of non-jpeg. I convert to Photoshop format and do all my manipulation in their format, then save a copy of the final image in Adobe's Photoshop format, then make another copy and save it as JPG, ready for sending to the place that does my prints. RAW and TIFF support better color and greater gamut (light range from dark to light) and you can see the difference after converting to jpeg so I want to avoid the conversion until the last step.