Do professional photographers use photoshop cs3??
I use a combination of Lightroom and CS3. I convert all of my images from RAW in lightroom and then do all other editing in photoshop like retouching and special effects. Photoshop, to an extent, can do what Lightroom does but it can really only work on one file at a time without a bunch of saving and copying where in Lightroom you can “sync” your images with the click of a button. If you are struggling with which to purchase, I would suggest Lightroom because like Photoshop, it is a product by Adobe… but that is just my opinion!
