5 Replies Latest reply on Jan 18, 2018 10:23 AM by johnv56043362

    White Balance

    johnv56043362

      Excuse my ignorance, I am relatively new to this and I expect my question goes beyond Lightroom.

      I thought that one of the advantages of capturing RAW files as opposed to JPEGs was that you could change the white balance.

      Lightroom seems to allow me to change the White Balance on .jpg files as well.

      What am I not understanding?

       

      Thanks

      John

        • 1. Re: White Balance
          Hal P Anderson Level 6

          You can change white balance on both kinds of files, but you'll get a better result with raw files.

           

          Hal

          • 2. Re: White Balance
            johnv56043362 Level 1

            Thanks Hal for the prompt reply.

            I'll have to try on both file types and see if I can figure out what you mean by a "better result".

            Regards

            John

            • 3. Re: White Balance
              Hal P Anderson Level 6

              I'm kind of colour-challenged, so I'm relying on what I've gleaned from the internet rather than from my own experience. Let me know what you find.

               

              Hal

              • 4. Re: White Balance
                elie_di Level 4

                Two important facts apply here:

                1. A Raw file is what its name implies; raw, unprocessed data from the sensor. The only operation that was done on it by the camera firmware was the digitizing of the sensor's analog output (voltages). A Raw doesn't even have color data, because sensor voltages are caused by the intensity of the light hitting it, not its color. The color is interpolated in by Lightroom along with a lot of other image adjustments, including WB. So when LR applies that processing it is the first time, like a flower being grown from virgin soil. A Jpg is the product of such processing, whether done by a Raw conversion application or by the camera firmware. The image data has been "baked in", it is a grown flower. You can do some tweaking - prune some branches, paint the petals with paint (a' la Alice in Wonderland), but you can't convincingly change a dandelion to a rose.

                2. Nowadays cameras write Raw data with 14 bit precision, or at least 12 bits. LR does its calculations to 16 bit precision. Jpgs contain only 8 bit data. In the conversion to 8 bits a lot of the original data is lost to rounding off, like my telling you I have 5 dollars when I really have 542 cents. Also, Jpgs are always compressed files; the first thing any app does when opening them is to decompress it. In these two operations more data is lost. High bit depth and abundant data gives flexibility in processing Raws that Jpgs can't have.

                • 5. Re: White Balance
                  johnv56043362 Level 1

                  Thank you for your detailed explanation.

                  I think I now understand that while some semblance of WB change can be achieved when working on a .jpg file, one would have much greater/broader control when applying changes to WB on a raw file before converting it to .jpg or other format.

                  Regards

                  John