Photoshop Creative

If you've got LR set to send the photo to CS3 as a TIFF, it will create a new one off your original every time. LR will not let you directly edit an original file. Now, once you have sent the photo to CS3 and done some editing there, you can save back to the file that LR creates. And, if you haven't already found it, you can set the format of the file for external editing to either TIFF or PSD. Right now it appears you have it set to TIFF. If you don't want that, just go to Edit -> Preferences and then the External Editing tab and set it there.

Thanks, Gene, that is what I needed to know

You're welcome.

Gene, thanks for the tip on the TIFF-PSD preference. I did notice that when using the PSD preference, it warns that you need to choose the Maximize Compatibility mode, which, as I recall, causes the PSD file size to get pretty large. Will have to look into that a bit....

I just took a quick look at some of my folders, and the finished PSD files tend to be 3 or 4 times the size of the imported RAW files, which I convert to DNG files upon import into LR. My DNG's are about 12M each, and the PSDs range from 35M to 50M each. I convert the PSDs to JPGs for uploading to my SmugMug site or sharing with friends and family, and the JPGs can be 3 to 6 Meg in size, depending.

Gene, that sounds right. On my little Canon G9, point & shoot (a 12 megapixel camera), the raw images are around 14 MB. The 'simple' TIFF that's generated by Lightroom is 65 megabytes, and adding a duplicate layer brings that to 130 MB!

No wonder I'm runnning out of room on my laptop hard drive....

TIFF's are expensive!