11 Replies Latest reply on Oct 1, 2012 6:43 PM by Noel Carboni

    Understanding image resolution and appearance across devices

    simonart Level 1

      I used CS6 standard.


      Why have some images have soft edges under retina (iPad 3) but sharp on a screen (non-retina)?


      Does this mean I will have to rework all my images to work with retina display? As most of my images are 72dpi, not sure if this relevant or not?


      Can someone kindly advice me the best ideal way to overcome this problem.


      Message title was edited by: Brett N

        • 1. Re: Lost
          c.pfaffenbichler Level 9

          Photoshop can not currently use the full resolution of a retina display, so the application is displayed resampled.

          Do the images also appear blurred when viewed with the Mac Preview?

          Edit: Sorry, that was not relevant as you mentioned your ipad.


          Your (edit) digital pixel images are hardly 72dpi, but ppi.

          And the resolution is usually not the relevant item, the pixel dimensions are.

          • 2. Re: Lost
            simonart Level 1



            Yes, some images are blurred with Mac Preview others are sharp. Can you kindly explain a bit more about pixel dimension? I am buffed by this.

            • 3. Re: Lost
              c.pfaffenbichler Level 9

              Many screen nowadays are far from 72dpi (the retina display being farther along than most others currently), so the old adage of providing 72ppi images for web purposes is pretty much moot.

              100 pixels are 100 pixels, no matter if the Photoshop file claims they represent 3.53cm or 0.85cm.


              My dragging Preview into this was irrelevant, though, I’m afraid.

              Edit: And I don’t know how Preview resamples images for displaying them at different magnifications.

              • 4. Re: Lost
                sudarshan.t Level 6

                Especially for retina display, I read this interesting article some time ago. This is for 'designing for web' on new MBP Retina. But, I guess the concept remains the same.


                http://www.webmonkey.com/2012/06/make-sure-your-site-looks-good-on-the-new-retina-macbook- pro/


                Read the section where they've shown a @media-query to show how to render excellent images on Retina display.

                • 5. Re: Lost
                  simonart Level 1

                  Right, I am getting there. So, I have noticed that some images when zooming in are sharp and other's very soft edges, and you can see that the file been compressed!


                  So it sound like that vector file format is the way to go.

                  • 6. Re: Lost
                    pf22 Level 2

                    Hi Simonart


                    I'm using CS5, have the New iPad with its Retina display and have reprocessed a number of my photos to display on the iPad, using it as a "digital portfolio" when I go on a shoot.


                    I shoot 18MP Raw files only, and output to a 16Bit uncompressed .tiff, which I work on all the way through my workflow 'til I get to final step of generating an 8Bit jpg at the display size required.


                    My final step now is to crop/resize my "finished" image to 2048 x 1536 - the size of the iPad's Retina Display - then sharpen to suit, usually a minimum of 100% Smart Sharpen, convert to 8Bit jpg, and upload to my iPad.


                    These days I mainly shoot gigging musicians in bars and clubs under available light only, no flash, have my lens' set permanently to f2.8, and all my images are absolutely razor sharp... within the available DoF of course! LOL!


                    Good luck


                    • 7. Re: Lost
                      Noel Carboni Level 8

                      See also this page:




                      View Source to see the HTML.



                      • 8. Re: Lost
                        simonart Level 1

                        Wow the images on the left are far better than on the right when zooming in on the retina iPad. 


                        Paul, Yes, I can see where you are coming from. You have given me something to think about cropping.

                        1 person found this helpful
                        • 9. Re: Lost
                          Lundberg02 Level 3

                          Why would you sharpen before converting?

                          • 10. Re: Lost
                            pf22 Level 2

                            simonart wrote:



                            Paul, Yes, I can see where you are coming from. You have given me something to think about cropping.


                            Yeah, the proportions of the iPad3 are a bit off; I usually send out 600x400 pixel images - I find the proportions pleasing - for display on, mostly, social networking sites etc, and while most people up 'til now have considered 1080 vertical to be "HD" (LOL!!!) that's been good enough. 


                            The Retina Display on both the iPad and MacBook Pro, is something of a game-changer image quality wise; we're now hearing rumors of an iMac with a Retinal Display! While that's still in fanboy nerdgasm territory - I've not seen any leaks out of the Apple supply chain about them having been sent sample displays - I think it really is just a matter of when, not if. 


                            Mind you, I for one will be happy if these new HiDef displays dissuade people from posting their scuzzy fonecam pics all over the web (LOL!) as c.pfaffenbichler indicated above, pixels is pixels!!!

                            • 11. Re: Lost
                              Noel Carboni Level 8

                              pf22 wrote:


                              scuzzy fonecam pics


                              Hear hear!


                              People used to say that the best camera is the one you have with you.  I beg to differ if the "one you have with you" is a microscopic chip in a corner of a cell phone.  Don't bother.