Best way to edit a JPG in Photoshop

Question

I want to edit alot of camera photos (captures in JPG format) to correct exposure (and sometimes framing and other) issues, but want to minimise any loss of quality when I re-save the file. Is the best way to open each image as Camera Raw, make the adjustments, then use "Save Image" from the Camera Raw screen to save my changes? I notice that this results in a smaller file size than the original (e.g. 1.95Mb vs 3.75Mb), but wanted to be sure that I was using the optimal method for opening/editing/saving so as not to lose too much image quality.

Answer 1

The way to minimize data loss when editing a JPEG is to resave using the same sampling and quantization tables as the original.

My guess the way to do that in Photoshop is to save in a lossless format (e.g., PNG) then converge to JPEG using some command line application that will allow you to specify the sampling and quantization tables.

Answer 2

If you are uploading them to a website then you can go File>Open (navigate to your file and open it) then make your changes and then go File>Save For Web. If you are not uploading these or trying to get a smaller file size then just use the normal save (File>Save (Or Save As)) the only time I would use Camera Raw is if I was editing a photo in a .raw file, as in directly from a camera. Even if I where to edit a raw file I would take it through Lightroom and make it a PNG (Highest quality, decent size) then go into Photoshop and open it with File>Open.