Announcement

Collapse
No announcement yet.

JPG compression artefacts

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

  • JPG compression artefacts

    A while ago i posted my first image to the database but unfortunately it was rejected and one of the reasons was for JPG compression artefacts. I did some research about it and tried to find a solution with no luck. Can someone recommend a way how to remove JPG compression artefacts (except Photoshop if possible)? Any help appreciated.

  • #2
    Hi, welcome to JP!

    JPEG compression artifacts happen when you dont export in the highest possible quality. With that I do NOT mean the size, but the quality itself. There are several options in your export window if you use Lightroom.

    I’m sure someone else can give a better explanation, but I thought I could add my two cents.

    regards!

    Comment


    • #3
      A JPG is a compressed file. It strips out information when you create it to make the file size more compact. You should aim to create and save files at the highest quality possible so that the least amount of compression occurs. Alot of "save for web" quality levels will create a much more heavily compressed file. In photoshop, I always leave my quality level at 12. The more you save a jpg over and over the more compressed it will get.

      So, basically what you need to do to avoid compression much as possible is ... shoot at the highest quality in your camera, such as RAW, or if you shoot jpg, then make sure it is set to the highest quality level possible (like large/fine). Don't be tempted to lower the quality to save space on your memory card. Just carry more memory cards. Then in your editing software, always save at the maximum possible quality.

      Hope this helps.

      Comment


      • #4
        Originally posted by B7772ADL View Post
        A JPG is a compressed file. It strips out information when you create it to make the file size more compact. You should aim to create and save files at the highest quality possible so that the least amount of compression occurs. Alot of "save for web" quality levels will create a much more heavily compressed file. In photoshop, I always leave my quality level at 12. The more you save a jpg over and over the more compressed it will get.

        So, basically what you need to do to avoid compression much as possible is ... shoot at the highest quality in your camera, such as RAW, or if you shoot jpg, then make sure it is set to the highest quality level possible (like large/fine). Don't be tempted to lower the quality to save space on your memory card. Just carry more memory cards. Then in your editing software, always save at the maximum possible quality.

        Hope this helps.
        Thank you for the tips. I always shoot in RAW and then convert it into JPG format. However, I'm entirely new into editing softwares and perhaps i could use some help how to save an image at high quality and low compression rate (i use GIMP).

        Comment


        • #5
          Originally posted by B7772ADL View Post
          always save at the maximum possible quality.
          And never modify a JPEG file to save it again : il will be re-compressed from the previous compressed version... Use non compressing transit files like .dng, .psd, .tif etc...

          Comment


          • #6
            As you ask to avoid Photoshop, I guess that covers other Adobe products such as Lightroom. Nikon provide a free RAW processing software for NEF captures. I wonder if other manufactures do the same or what other RAW processing software is available.
            --
            David dubya Wilson

            Comment


            • #7
              Originally posted by Aldgyte View Post
              As you ask to avoid Photoshop, I guess that covers other Adobe products such as Lightroom. Nikon provide a free RAW processing software for NEF captures. I wonder if other manufactures do the same or what other RAW processing software is available.
              Yes, cannon does offer a software which is called digital Photo Professional 4, it is intended for RAW processing either and it also is free for cannon owners.
              A nice feature is, that it does have a feature of automatic dust removal if the camera is calibrated properly and does know where the spots are.

              Comment


              • #8
                Originally posted by Arso Gouno View Post

                Thank you for the tips. I always shoot in RAW and then convert it into JPG format. However, I'm entirely new into editing softwares and perhaps i could use some help how to save an image at high quality and low compression rate (i use GIMP).
                I'm not too familiar with GIMP, so I just downloaded it to take a look. It seems you have to "export" the files to save it as a jpg, as gimp uses its own native file extension. Once you enter the file name and click on export, as long as you have selected jpg, it brings up a jpg box where you can alter the quality, I would set the quality slider to 100. Then there is an advance options function. I would go into this and make sure "optimise" is not selected as this suggests a smaller file size will be created. It says you can use the "smooth" slider to blur out jpg artefacts, but I wouldn't use this as it suggests in the manual you can result in a blurry image.

                Comment


                • #9
                  Originally posted by B7772ADL View Post
                  A JPG is a compressed file. It strips out information when you create it to make the file size more compact. You should aim to create and save files at the highest quality possible so that the least amount of compression occurs. Alot of "save for web" quality levels will create a much more heavily compressed file. In photoshop, I always leave my quality level at 12. The more you save a jpg over and over the more compressed it will get.

                  So, basically what you need to do to avoid compression much as possible is ... shoot at the highest quality in your camera, such as RAW, or if you shoot jpg, then make sure it is set to the highest quality level possible (like large/fine). Don't be tempted to lower the quality to save space on your memory card. Just carry more memory cards. Then in your editing software, always save at the maximum possible quality.

                  Hope this helps.
                  Hi, I was just wandering how you got to save your photos at a quality level of 12? for me it only goes up to 7 and theres always artifacts on photos that were previously good for uploading.

                  Comment

                  Working...
                  X