21 Replies Latest reply on Jul 14, 2011 4:03 PM by the_wine_snob

    Why are still images importing larger than their size?

    Kurt Lang Level 1

      Per instructions in a thread I had here last week, I created all of my DVD still images at 720 x 534 pixels for Premiere Pro CS5.5. But when they are brought into a DVCPRO50 NTSC Standard sequence, they are being heavily clipped. The original in one example is this:

       

      80.jpg

      But when that same images is brought into PP, it is sized up like this:

      scaled.jpg

      It's still proportionally correct, but a lot of the top and bottom of the image are gone. The encoded MPEG-2 sequence and disk I've done as a test display just like that.

       

      Why is PP doing this, and how can I get it to use images built to the correct size to be used 1:1 in a sequence instead of being scaled to about 115% of size? Hate to compare this way, but this was never an issue with Final Cut Pro, which I'm switching from. Stills created to the size FCP needed of 720 x 540 displayed and finished exactly as they were made in Photoshop. The only image area lost was the normal bit of overscanning DVDs display at on your TV.

        • 1. Re: Why are still images importing larger than their size?
          the_wine_snob Level 9

          Kurt,

           

          It appears that your Image size is larger than the Frame Size of your Project. For the DVCPro NTSC, your Frame Size should be 720 x 480, and with a PAR for either Standard/4:3, or Widescreen/16:9. Now, your images are most probably square pixels, rather than the non-square used in the Video, but I am not sure how you came to the dimensions, 720 x 534.

           

          That difference between 720 x 480 and 720 x 534 looks about what I see being cropped off, in this case on the vertical right at 1.1125%.

           

          Good luck,

           

          Hunt

          1 person found this helpful
          • 2. Re: Why are still images importing larger than their size?
            Kurt Lang Level 1

            Hi Bill,

            but I am not sure how you came to the dimensions, 720 x 534

             

            That was a result of this thread. Todd_Kopriva pointed me to this page. The graph states that the square-pixel equivalent for CS4 or later should be 720 x 534. This didn't seem unusual to me since FCP uses 720 x 540. The same page though has a graph right below that which says (next to NTSC):

             

            Footage has a 720x486 or 720x480 frame size, and the desired result is a 4:3 frame aspect ratio.

             

            Which seems to indicate you should be creating your stills to exactly the frame dimension of 720 x 480 so they don't get scaled to fit.

             

            However, just to add to the confusion, the page also states that the square pixel size for NTSC widescreen should be 872 x 486, even though the frame size is stated the same as 4:3 NTSC, 720 x 480. This larger width of 872 pixels for widescreen also makes more sense to me since I can't see where anyone would want a 720 pixel width image to be stretched that much for widescreen. Just for comparison, FCP calls for 853 x 480 for widescreen.

             

            Now, your images are most probably square pixels, rather than the non-square used in the Video

             

            Correct, square pixel TIFFS out of Photoshop.

             

            So should the stills be created to 720 x 480, and not the 720 x 534 size the graph calls for?

             

            Thanks.

            • 3. Re: Why are still images importing larger than their size?
              SFL46 Level 3

              The 720 x 534 square pixel kludge

              will work only if the option to stretch the image to fit is turned on.  The theory is that PrPro will stretch the image back down to 720 x 480--with what approximates 0.9 PAR.

               

              If you are going to scale the pictures beforehand, first convert them to 0.9 PAR and then crop to 720 x 480.

               

              One question though, are your images portrait format?  720 is the width, not the height.

              • 4. Re: Why are still images importing larger than their size?
                Kurt Lang Level 1
                So should the stills be created to 720 x 480, and not the 720 x 534 size the graph calls for?

                 

                Simple test answered that question. I made two images at 720 x 480. Just a white background with a perfect circle on one, and a perfect square on the other. Brought into a sequence, they end up stretched in the height. If you simply do a Canvas Size change in PS to make them 534 pixels high, then they display proportionally correct in the sequence. So 534 pixels is correct, at least as far as getting the images to be undistorted in PP.

                 

                Still doesn't explain why the entire height of image is not used in PP. The NTSC height distortion and MPEG-2 compression is enough of a killer on overall sharpness from the original without scaling it too.

                • 5. Re: Why are still images importing larger than their size?
                  Kurt Lang Level 1
                  One question though, are your images portrait format?  720 is the width, not the height.

                   

                  Yes, portrait orientation.

                   

                   

                  The 720 x 534 square pixel kludge will work only if the option to stretch the image to fit is turned on.

                   

                   

                  Took me a few minutes to find that one in the preferences since there was nothing by that phrase. It's Default scale to frame size. That does make 720 x 534 square pixel images fit correctly. Yay! Does mean though that there's a lot of scaling going on. Boo!

                   

                  Now, this is an interesting point.

                   

                  If you are going to scale the pictures beforehand, first convert them to 0.9 PAR and then crop to 720 x 480.

                   

                  Something I noted many moons ago in Photoshop, but never had need to pay attention to it before. Not sure how to convert them to PAR. I can change the view to NTSC, but I think that's just PS displaying the image distorted, not an actual non square pixel change to the image.

                  • 6. Re: Why are still images importing larger than their size?
                    the_wine_snob Level 9

                    Kurt,

                     

                    Looks like you are on the correct path.

                     

                    For portrait/vertical orientation material, you might find some of the tips in this ARTICLE useful.

                     

                    I often have to deal with both portrait and landscape material, and use variations on the above.

                     

                    Hope that gives you some ideas and good luck,

                     

                    Hunt

                    • 7. Re: Why are still images importing larger than their size?
                      Kurt Lang Level 1

                      Ha! First I need to correct myself. I did a "monkey see, monkey do" response here:

                       

                      One question though, are your images portrait format?  720 is the width, not the height.

                       

                      Yes, portrait orientation.

                       

                       

                      Obviously an incorrect answer. They're landscape orientation. 720 pixels width, 534 height.

                       

                      Thanks for the link. A nice artsy way of doing a slideshow rather than just image to image.

                       

                      Turning on the sizing option in PreP's preferences has me going the way I expected. I'll just have to live with the fact that you can't avoid softening of your images in SD since both NTSC and PAL display stretched. No matter how sharp your fixed image is, it's going to scale, and only in one dimension at that, when displayed on a TV.

                       

                      Just too used to almost 30 years of prepress work on high res images. Still learning video.

                       

                      Secondary question. An Adobe employee had this comment in another thread:

                       

                      So the right workflow would be: use SDTV PAL or SDTV NTSC as project working space, and then use SDTV PAL 16-235 or SDTV NTSC 16-235 as output profile, in the Color Management tab in the Output Module. This way, you'd use the full PAL or NTSC color spaces for rendering and legalize the output for the rendered file. Works beautifully. No need to use Levels or the Broadcast Colors effect to legalize color/luminance values.

                       

                      NTSC working space being the color space assigned to your fixed and video images. But a bit lost where he means to apply NTSC 16-235 for output. I'm guessing he means when you do a Command+M to start an Export to MPEG-2 of your sequence. You can pick a TV Standard, or Automatic (based on source), but through all of the choices, there isn't an option to select a specific profile. So I'm not sure where you're supposed to apply this translation.

                       

                      Edit: Found it. He's referring to After Effects.

                      • 8. Re: Why are still images importing larger than their size?
                        SFL46 Level 3

                        In Photoshop, if you change the PAR of an image in Photoshop, the image will be converted and saved in that PAR.  However, the photoshop option to display the image as square or a different PAR is not recorded.

                         

                        If you save a 720 x 480 image as sqaure pixels in Photoshop, properties in Pr Pro will show the PAR as 1.0.  If you convert the image to PAR =0.9, the PrPro properties will show the PAR as 0.9--which is what your sequence preset

                         

                        PrPro scales onl;y if your image dimension don't match the sequence presents

                        • 9. Re: Why are still images importing larger than their size?
                          Kurt Lang Level 1
                          PrPro scales only if your image dimension don't match the sequence presents

                          So would it be a correct assumption that by building the square pixel images at 720 x 534, which is what Pr Pro wants for NTFS 4:3 DVDs, they shouldn't be scaled at all, despite the actual frame dimensions are 720 x 480?

                           

                          I've built a couple of small test DVDs, and the output on a TV screen I think is about as sharp as you could expect a DVD to be, using 720 x 534 stills.

                          • 10. Re: Why are still images importing larger than their size?
                            SFL46 Level 3

                            NO, the DVD standard in NTSC is 720 x 480.   If you used the DV present in creating your sequence, that's what you'll get.  Your inported images need to be PAR 0.9 and 720 x 480.

                             

                            The 720 x 534is a kludge of sorts.  Note that 534 x 0.9 is 480.  It is used when you can't set the image PAR, but Photoshop allows you to do this.

                             

                            If your image si 720 x 480 PAR=0.9, scale to frame has no effect as the image is already the frame size.

                            1 person found this helpful
                            • 11. Re: Why are still images importing larger than their size?
                              Jim_Simon Level 8

                              You guys are all on the wrong track, here.  PAR adjusts horizontal resolution, not vertical.  For square pixel conversions, you should be working with the 720, not the 480.

                              • 12. Re: Why are still images importing larger than their size?
                                Kurt Lang Level 1
                                NO, the DVD standard in NTSC is 720 x 480.

                                Yes, I realize that. But after trying it both ways (one test video built with PAR images at 720 x 480, one using square pixel 720 x 534 images), there really was no noticeable difference between the two videos. Not even when viewed on a 40" LCD TV.

                                 

                                I think a lot of that can be contributed to Adobe's vastly superior encoding. I had read it was better than Final Cut Studio's Compressor, but I wasn't ready for that big of quality difference.

                                 

                                Given that it works well enough to suit me (and those who know me know that I am VERY picky about color and image clarity/sharpness), I'll just keep using 720 x 534 for 4:3 DVD, and 872 x 486 for DVD widescreen.

                                 

                                Thanks to all for your input. I've picked up the CS5/5.5 Adobe Classroom In a Book series for Premiere Pro (which covers PP, Encore, Audition and Media Encoder) and another for After Effects. I've had books in this series for other apps and know they don't cover everything, but they give you a good start.

                                 

                                I'm sure I'll be back with more questions.

                                • 13. Re: Why are still images importing larger than their size?
                                  SFL46 Level 3

                                  Well yes,  but the "theory" behind the kludge is to bring in the sqaure pixel image as

                                  720 x 534.  When you import this to PrPro with scale to frame enabled, PrPro "stretches" the vertical 534 to 480

                                  --the effect of which is to yield a PAR of 0.9  or pixels that are only 0.9 as high as they wide

                                  • 14. Re: Why are still images importing larger than their size?
                                    Jim_Simon Level 8

                                    Nope, that's still backwards.  When the PAR changes, it's only in the HORIZONTAL direction.  So the pixels at .9 are thinner than pixels at 1.0, but both are the exact same height.

                                     

                                    Images being converted in Photoshop should have a 480 vertical if being used in a 480 sequence.  You can adjust the 720 for either DV or square pixels, but the vertical will always be 480 for NTSC.

                                    • 15. Re: Why are still images importing larger than their size?
                                      SFL46 Level 3

                                      Well, I did not invent the kludge.  When I want 720 x 480 par 0.9, I do the conversion in Photoshop using the menu options.

                                       

                                      So, why it works, I guess I don't know.  While I've seen the kludge shown as 720 x 534 square pixels, I've nver seen it shown as 800 x 480 or 648 x 480, as you suggest should be used.

                                      • 16. Re: Why are still images importing larger than their size?
                                        the_wine_snob Level 9

                                        Since the PAR affects the horizontal, take a look at 655 x 480 with a PAR = 1.0 (Square Pixels). That is 720 x 0.91.

                                         

                                        Good luck,

                                         

                                        Hunt

                                        • 17. Re: Why are still images importing larger than their size?
                                          Jim_Simon Level 8

                                          If you want 4:3 aspect, it should be 640 x 480 square pixel.

                                          • 18. Re: Why are still images importing larger than their size?
                                            SFL46 Level 3

                                            I guess I don't understand.  This is an excerpt from the CS help.  This seems to be inconsistent with what the last two posts said.

                                             

                                             

                                            Composition settings presets for square-pixel equivalents of standard definition formats have changed as follows:

                                            format

                                            pixel dimensions in After Effects CS4 and later

                                            previous pixel dimensions

                                            NTSC D1 square-pixel equivalent

                                            720x534

                                            720x540

                                            NTSC D1 Widescreen square-pixel equivalent

                                            872x486

                                            864x486

                                            PAL D1/DV square-pixel equivalent

                                            788x576

                                            768x576

                                            PAL D1/DV Widescreen square-pixel equivalent

                                            1050x576

                                            1024x576

                                            • 19. Re: Why are still images importing larger than their size?
                                              the_wine_snob Level 9

                                              Jim,

                                               

                                              With a PAR = 0.91, will this still be the same?

                                               

                                              Hunt

                                              • 20. Re: Why are still images importing larger than their size?
                                                the_wine_snob Level 9

                                                Not sure where that chart is coming from, but HERE is the official Adobe chart.

                                                 

                                                Good luck,

                                                 

                                                Hunt

                                                • 21. Re: Why are still images importing larger than their size?
                                                  Jeff Bellune Adobe Community Professional

                                                  Here's why 648x480 is better than 720x534.  You have to scale the 720x534 (1.0) image down to 90% to get it to fit in a 720x480 (0.9) sequence.  The 648x480 (1.0) image fits perfectly at 100%.  Both methods will work.  The question is: how much damage to the quality of your image does scaling to 90% do?  Only you can decide.

                                                   

                                                  Examples:

                                                  534AtScale90.png

                                                   

                                                  648AtScale100.png

                                                  -Jeff