5 Replies Latest reply on Aug 17, 2016 12:37 PM by Jao vdL

    Exporting as jpeg for a Canvas Print

    quinntai97

      I recently shot Chicago's skyline at night and want to make a canvas print out of it (probably printing from Costco, this is my first time). They only accept jpegs, so I've been trying to export the image from lightroom accordingly. However, I get this weird ripple effect in the jpeg, which I assume is from the compression algorithm. Is there anyway I can reduce the effect of the compression more? Or will this not matter on a 16x48 canvas print?

       

      This is the exported jpeg with the ripples:

      help1.PNG

       

      This is how it looks before I export it:

      help2.PNG

       

      I am exporting as jpeg (duh) with sRGB and the slider all the way up to 100.

        • 1. Re: Exporting as jpeg for a Canvas Print
          Jao vdL Adobe Community Professional & MVP

          Do you mean the posterization in the sky portion? If at quality 100 you still see it, you can't do anything to make it better in the jpeg output. You can try soft proofing for sRGB and seeing whether by any chance the sky portion is out of sRGB gamut. It is possible that that is the problem. What version of Lightroom are you using? This might also be a quantization issue that got resolved in later Lightroom versions by dithering (adding noise) to the output image.

           

          You're unlikely to be able to see minor posterization in the final print as in general the printers are not able to produce as smooth gradations as you are able to display on screen but that is pretty hard to predict.

          1 person found this helpful
          • 2. Re: Exporting as jpeg for a Canvas Print
            quinntai97 Level 1

            So posterization is the term I was looking for...and yes, that is what I'm referring to. I'm using Lightroom CC, so I believe it's up to date? I tried soft proofing for sRGB just now, and it appears the only parts out of gamut are the buildings.

             

            help3.PNG

            • 3. Re: Exporting as jpeg for a Canvas Print
              ssprengel Adobe Community Professional & MVP

              Add some noise using Effects:

               

              And maybe do some smaller, cheaper test prints of just a portion of the image that includes the sky and part of a building, to see how good or bad the larger canvas might look.

              1 person found this helpful
              • 4. Re: Exporting as jpeg for a Canvas Print
                quinntai97 Level 1

                Adding a little noise seems to have helped. The posterization is still there, but it's much better now. Thanks everyone for your help!

                • 5. Re: Exporting as jpeg for a Canvas Print
                  Jao vdL Adobe Community Professional & MVP

                  You might also have more success taking the image into photoshop and doing the conversion to sRGB and to 8 bits there before saving to Jpeg. The difference in calculation tool chain might just be big enough to solve the issue. Photoshop also does dithering (I.e. Adding a bit of noise) when changing color spaces and bit depth perhaps a bit more reliably (more history there)