Announcement

Collapse
No announcement yet.

Equalisation. JP versus PS CC

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • Equalisation. JP versus PS CC

    This shot was rejected for .jpg compression and noise.
    JetPhotos.com is the biggest database of aviation photographs with over 5 million screened photos online!


    The sky received absolutely no processing at all. The first image here is the equalised image in JP. The second image is the equalised version in Photoshop CC.

    Click image for larger version

Name:	JP equalise.jpg
Views:	1
Size:	265.5 KB
ID:	1045781


    Click image for larger version

Name:	PS equalise.jpg
Views:	1
Size:	1.06 MB
ID:	1045782

    This is why I believe that decisions are being made based on the equalised image which is totally unfair, rather than the uploaded image. There is absolutely nothing in the PS equalised version to indicate compression or excess noise and I don't see any artefacts in the uploaded image.
    I have reuploaded a reprocessed version but you are probably going to think that it is the unchanged original image. I assure you that it isn't.

    Constructive comments would be welcomed.
    Last edited by brianw999; 2018-11-11, 14:05.
    If it 'ain't broken........ Don't try to mend it !


  • #2
    all big pixels in sky are visible on the non-equalised version, if that's not visible to you then the contrast of your screen might be the issue. There's no reason for such compression in sky and the reason for that compression should be the main concern here.

    The equaliser tool on JP is very powerful but as you know, crew members are only supposed to reject when it's visible on the non-equalised version, which is the case here.

    cheers
    Alex

    Comment


    • #3
      You know I screen more than anyone, and I've never rejected an image because too much compression was visible "based on the equalised image", so your assertion that this is an unfair process is not based on any hard facts that I am aware of. Now that my attention has been drawn to it, I can certainly see the sky is quite blotchy without doing anything to the original image, but even so I would almost certainly have noticed it and likely voted to reject (I did not screen the image above) for the same reason had I actually been the one to screen it.

      Comment


      • #4
        What I don’t understand is how the sky takes on the the blotchy compressed appearance when it has absolutely no processing applied to it. When I process pictures that have a completely blue sky I create a background layer at the start of the processing procedure, process as required for the aircraft and then delete the background sky leaving it as it came out of the camera in the original RAW file. I then save at maximum resolution. I really dont know what is happening here.
        If it 'ain't broken........ Don't try to mend it !

        Comment


        • #5
          Originally posted by brianw999 View Post
          What I don’t understand is how the sky takes on the the blotchy compressed appearance when it has absolutely no processing applied to it. When I process pictures that have a completely blue sky I create a background layer at the start of the processing procedure, process as required for the aircraft and then delete the background sky leaving it as it came out of the camera in the original RAW file. I then save at maximum resolution. I really dont know what is happening here.
          Assuming you're starting with the RAW file, and not an in-camera processed jpeg, it's definitely something to do with your processing. I've never had skies come out looking like that after converting an image to jpeg with no processing otherwise done.

          Comment


          • #6
            Originally posted by brianw999 View Post
            What I don’t understand is how the sky takes on the the blotchy compressed appearance when it has absolutely no processing applied to it. When I process pictures that have a completely blue sky I create a background layer at the start of the processing procedure, process as required for the aircraft and then delete the background sky leaving it as it came out of the camera in the original RAW file. I then save at maximum resolution. I really dont know what is happening here.
            If you are having issues with this then there can be no hope for us out here trying to get to grips with it!!

            Comment


            • #7
              Originally posted by dlowwa View Post
              Assuming you're starting with the RAW file, and not an in-camera processed jpeg, it's definitely something to do with your processing. I've never had skies come out looking like that after converting an image to jpeg with no processing otherwise done.
              If the colour gradient in the sky is smooth/low enough, I would expect that the jpeg algorithm would produce blotching or banding, regardless of how the sky got that way. Granted, I would also expect that even a low ISO shot on a full frame sensor would still have enough noise in the sky to stop this from happening. Bottom line, I don't think it's a given that this is something that was done in post processing, other than possibly being amplified by resizing.

              A Spread function over an appropriate colour selection (careful with the feather and edges!) can undo the "damage", but I'm not sure how it fits in to your workflow Brian.

              Comment


              • #8
                Originally posted by Quebec Golf View Post
                If the colour gradient in the sky is smooth/low enough, I would expect that the jpeg algorithm would produce blotching or banding, regardless of how the sky got that way. Granted, I would also expect that even a low ISO shot on a full frame sensor would still have enough noise in the sky to stop this from happening. Bottom line, I don't think it's a given that this is something that was done in post processing, other than possibly being amplified by resizing.
                That's not the kind of blotchiness we're seeing here, at least not to my eyes. If it were, I would have suggested converting to a tiff first, editing, re-sizing, and then saving as jpeg, as that usually remedies the banding issue on fine gradients in the sky. What's happening in Brian's image(s) looks like something else.

                Comment


                • #9
                  Looks to me similar to this, https://www.jetphotos.com/photo/9114054 and I can see the noise/compression.

                  How are you saving the JPEGs and at what quality?

                  Comment


                  • #10
                    Originally posted by NeilA330 View Post
                    Looks to me similar to this, https://www.jetphotos.com/photo/9114054 and I can see the noise/compression.

                    How are you saving the JPEGs and at what quality?
                    Save as a .jpg is the very last action in my workflow. I save at highest resolution (12)
                    If it 'ain't broken........ Don't try to mend it !

                    Comment


                    • #11
                      I think that I have fixed the problem. I have set everything to zero in ACR that involves noise reduction and sharpening. All I use ACR for now is resizing, setting the colour channels histograms, selecting remove chromatic aberration and selecting the lens correction value for my 18-300.

                      When I go to PS CC I select the aircraft only and use Pik sharpening and Pik dFine noise reduction.

                      This basically means that the sky gets absolutely no processing at all. This is the resulting equalisation as seen in JP....
                      Click image for larger version

Name:	38AAC2BB-B51E-4C27-B1FE-79188BF09AF9.jpeg
Views:	1
Size:	1.11 MB
ID:	1031355

                      Compared to the rejection...
                      Click image for larger version

Name:	6DC18F02-4461-42D0-8E1E-C6E0508FD849.jpeg
Views:	1
Size:	1.07 MB
ID:	1031356

                      They are admittedly different frames but they were taken within a second or so.

                      Here is another example this time from the same frame. Rejection first, then the latest upload...
                      Click image for larger version

Name:	3854EF97-8D65-4669-83FD-C119419AB051.jpeg
Views:	1
Size:	888.3 KB
ID:	1031357

                      Click image for larger version

Name:	69D4E257-EC63-4D98-BD4A-9F4568E93C5B.jpeg
Views:	1
Size:	1.21 MB
ID:	1031358
                      If it 'ain't broken........ Don't try to mend it !

                      Comment


                      • #12
                        So you're saying it was your processing, hmmm..

                        Comment


                        • #13
                          Originally posted by dlowwa View Post
                          So you're saying it was your processing, hmmm..
                          In the past, decisions were being made based on the equalised image and I was concerned that that was happening again. The difference between you and me is that I dealt with it privately via email and/or PM direct to the persons concerned. That was back in the days when, as a senior I could see who was screening. I don’t have that facility anymore so I have to use an open forum. Clever comments in a public forum like yours quoted here don't do anything to help at all. As a senior Dana you need to revisit how you speak to people in open forum.
                          And... I think I will stop there before I say something else that will start a firestorm.

                          Following on from my opening post I was asking for help to identify the source of my processing problem. I had previously been advised to initially work on the RAW file in ACR before going into PS CC and it didn’t cross my mind that the fault could be with ACR. Obviously, having had a “face slap” moment it has now sunk in that the instant you start playing with an image faults can occur.

                          Finally, an open appeal to the managers of JP concerning the JP equalisation tool.

                          Thousands of uploaders around the world use the Adobe based equaliser but they are judged by around 30 or so who use the much stronger JP version. The uploaders have to upload to be able to use the JP tool and delete the upload if there is a fault after copying the JP image for reference which is a bit of a pain in the butt. So, two ideas spring to mind.
                          1. Make the JP equaliser available as a stand alone download.
                          2. Dump the JP version and use the Adobe version in JP.
                          If it 'ain't broken........ Don't try to mend it !

                          Comment


                          • #14
                            Thank you for the suggestion Brian, as you know this has been discussed many times among the crew. Somehow, my personal opinion here, is that CS equalising tool doesn't do the job correctly, specially on light sky areas. Dozens of times they were spots that were fully visible unequalled, where the CS equaliser tool would show nothing more while the JP tool would make it much clearer. As screeners we need a tool we can rely on all type of skies, not only dark ones. We later decided to make it available to all so they can use it just like screeners. I also believe that a 2sec check after uploading a picture isn't much to ask to uploaders compared of the quantity of time crew members spend on checking their pics on screening.

                            And, I can also suggest to the following to make your CS tool just as strong as our JP tool

                            1st the image itself, maybe you can spot the dust ? It's visible over the trees



                            As you can see, second image shows the sky with normal CS equalising tool, not much visible than previous version



                            Open "curves" and modify the line as shown - Then the dust is much more visible, it's an extra step but since I'm using it my rejection rate for dust is close to zero, really helped me improve.



                            hope it helps

                            Alex
                            Attached Files
                            Last edited by Alex - Spot-This !; 2018-11-14, 13:18.

                            Comment


                            • #15
                              Great advice, thanks very much Alex. I have a keyboard action set saved to equalise (ctrl+f3) ....work on dust.... Unequalise. (Alt+f3). I’m wondering if the curves activity could be incorporated into that action set.
                              If it 'ain't broken........ Don't try to mend it !

                              Comment

                              Working...
                              X