ProPhoto or Srgb?

You don't overwrite your original image.

And you must have the full version of Photoshop (not Elements) AFAIK.

Let me give you a ProPhoto example:

* Edit as much as you can in LR (because it's working in its own colour space that will give the best results)
* Export to a PSD, TIFF (but not JPG!!) in 16-bit ProPhoto colour space
* Open in Photoshop and edit and apply PP as required
* Save your image

When you want to print from this image:

* Use the print dialog
* The settings vary depending on your printer, whether you have a custom profile, and what your results your drivers give you.
- e.g. Color Management: "Proof", "Photoshop Manages Color", "Printer Profile = Epson blah blah blah", "Rendering Intent" = Relative Colormetric. (and turn OFF colour management in the printer's specific dialog settings)
- e.g. Color Management: "Proof", "Printer Manages Colors" (and turn ON colour management in the printer's specific dialog settings)

Now, when you want to output to screen:

* Flatten image
* Resize and sharpen
* Edit / Convert to Profile / sRGB
* File / Save for Web
* Use a different name, like "MyImage_1000px_sRGB.jpg"

(Do not overwrite the original image!)

When you want to prepare for professional online printing:

* Flatten image
* Resize and sharpen according to their requirements
* Edit / Convert to Profile / [ their colour profile ]
* File / Save as JPG
* Use a different name, like "MyImage_18x12_ProAM.jpg"

(Again, do not overwrite the original image!)


You need a clear distinction between LR, files-in-process-of-editing, and finished-output-files.

I tend to use subdirectories for that purpose.

If you don't have to use Photoshop you can, as I said, just use the Export dialog to convert directly to the professional printer's profile. But again, it's best to name the file appropriately.

AND, unless you are saving space it's a good idea to embed the color profile in the output image. That way, you'll always know for sure what colour space it's in!

Matt