I'm glad it helped

Here's the link you asked for :

http://www.chat-africa.co.za

 Hope that helps rather than adding confusion

It certainly does help!  You've given me an A Ha! moment LOL

Thanks so much.  Would you mind sharing a link to your website?

 PS:  Ceri, my apologies for hijacking your thread.

If you view a RAW file, it will display using the parameters that would have been used to produce the JPG. If you change any of those, like white balance, exposure, saturation, etc., the new values are saved along with the file and are used next time you view it, but the file itself is not changed and is still the original RAW file.

Some lossless compression is used to generate a RAW file, how much depends on the camera manufacturer.

 A JPG generated by the camera, on the other hand is produced from the RAW image in camera, even on cameras that do not allow a RAW setting. The JPG is produced using the parameters set on the camera at the time, including white balance., etc. These cannot, therefore, be changed afterwards. JPG uses a lossy compression method, enabling much smaller files to be produced, resutling in faster write times to the memory card, fast transfer to your PC and faster download times from a web site. Due to the lossy method, they can lose fine detail, however. In camera processing usually uses a lot of sharpening, often a bit too much, but it does produce punchy sharp pictures that most casual users will be happy with, so it's a pretty good system.

You only need RAW when you are going for that bit extra, as per the questions being asked here, then you have more control, being able to fit the white balance, final exposure, saturation, contrast, sharpening, etc. to the individual picture, instead of having them all done to the same exact method the camera has decided on

 For printing, almost any program can print a JPG, as it is the base level. Photoshop and many other programs can print direct from a RAW image or any other format you might want.

For printing calendars, posters, pictures for framing, etc. you want the highest possible definition. For this the publisher/printer will prefer a TIFF file, a format developed specifically for the printing and graphics industry. For this you need to start with a RAW image, as converting a lossy JPG will produce much poorer results. Don't get that statement wrong, you can produce a good image and a good conversion from a good JPG, but if you have a RAW file to start from, it's going to be a fair bit better.

From the RAW file, I adjust as needed to suit the picture, then open for final editing, adjusting shadow areas if needed and use unsharp mask to apply the minimum needed to bring the picture out. I then save it as a TIFF file, which is uncompressed, so no detail can be lost from that point on. TIFF files are big though, the ones from my camera come out at about 35MB each, so they are only used for publishing houses.

All my web pics are reduced to one megapixel resolution, since that's all you can see on a PC screen anyway and they're all saved as JPG for small download size and speed.

Hope that helps rather than adding confusion

Thanks, Brian.  That's interesting.  Once you've modified an image, can it be saved as a copy in "raw?"

I only recently understood that "jpeg" involved compression.  And I had always thought that in order to print, the digital image had to be in "jpeg" format.

I don't have Photoshop (way to expensive for an amateur like me).  I use Paintshop Pro.

Not that I do a lot of manipulating the photo's after the fact.

Brian,

thanks for all this great info.

I'm learning a lot

Olympus tend to use much less compression, so their RAW files are usually bigger than others and the TIFF file option only Olympus has used is a lot bigger

I'm not surprised you could only get one picture on a 16MB card

The larger file sizes will inevitably take longer  to write to the card.

I use 4GB cards and shoot in RAW plus small JPG and get about 390 shots on a card. I use the JPG for reviewing and sorting, then finalise WB, exposure, etc in Photoshop using the RAW images. I keep the RAW images so that I can produce large uncompressed high quality images for printing and publication.

I finally found "raw" on my camera (and Olympus) and could only get one image because my card wasn't large enough.  Also noticed it took longer transfer time to record the image.

That was only a 16mb card. 

 Yes and yes

Careful using RAW, it's addictive and a lot more versatile than JPG You'll use a lot more memory card and disk space, but you'll never go back lol

 Just think of those sunsets now and setting just exactly the right white balance back on your PC to give the vivid colours you saw with your own eyes ! heh heh

The master has spoken!

Thanks Brian to go to all the trouble of looking it up for me. I have never used RAW, but might try it later on when I had a good look at my camera to see where it is

I will certainly try all your suggestions. I have this camera already some time and have never tried much, only went snapping on auto.

You have given me advice before and I tried it out and it worked, so be sure I will try this too.

I can just set the cam on RAW and change it later to JPG if I want? Can I switch between the settings from pic to pic?