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too much/too little contrast

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  • too much/too little contrast

    Hi guys,

    Have had this shot rejected for too much/too little contrst twice now. I took the contrast down but still it got rejected for that reason. Do I need to take it down more?

    Cheers for your wisdom..


  • #2
    Hi Duncan,

    There's a remark from the screener in the rejection email you got.

    Send me your original and I'll have a crack at it, if you like.


    • #3
      There's a remark from the screener in the rejection email you got.
      ....which was me ! I wondered if I'd see that one again in these forums.

      Looking at the EXIF it seems that you overexposed the original in camera by 1/3rd of a stop which has caused the white roof to become very blown. Starting from scratch with the processing, reduce the exposure until some detail comes into the roof and then use the curves function to "close the gap" so to speak between highlights and dark tones. Hopefully there will still be enough detail in the roof for it to work.

      I had a go with your already processed image but had to use shadow/highlight to show what I mean. If you do use shadow/highlight IT IS ESSENTIAL that you exclude the sky from the processing to avoid haloes.
      This effort gives some idea of what we are looking for but even this is rather blown out on the roof and would likely be rejected. The tail end is also rather soft and blurry.....

      If it 'ain't broken........ Don't try to mend it !


      • #4
        Thanks Brian,

        Yeah I was wondering about the roof but couldn't do anything with it. I think this one may have to stay in my personal file.


        • #5
          If you do use shadow/highlight IT IS ESSENTIAL that you exclude the sky from the processing to avoid haloes.


          Can you explain to me how do you do this?
          Everything I can learn from you guys about editing is more than welcome



          • #6
            Ohhhhh, buggerit ! I knew I'd make more work for myself by saying that !!

            Shadow/highlight is a very useful tool which does much the same as curves adjustment but it has one annoying habit, that does not occur when you use the curves tool, in that it tends to create haloes around defined line areas such as wings, fuselages, tail fins, landing gears and horizons and treelines. Unfortunately, these are all parts of our favourite subject here...aeroplanes !!

            What do haloes cause ? ........ they cause overprocessed rejections every time.

   to avoid haloes and yet still use the shadow/highlight tool ?

            Our photographs tend to be composed in one of three ways.

            1. Airborne aircraft wholly surrounded by sky.
            2. Airborne aircraft against a sky and horizon background.
            3. Aircraft on the ground with a horizon/skyline in the background.

            One of the first things to do in your processing before using shadow/highlight is to set the exposure. The best way to do this is to get it right in the camera in the first place but sometimes you have to adjust it in Photoshop.

            For a type 1 photo that has a blue sky that, when selected with the magic wand tool, completely surrounds the aircraft you can select the sky, go to "Select"..."Inverse" and bingo ! you have now selected the aircraft only for your processing.
            Using the shadow/highlight tool now will only cause the aircraft to be processed. The sky is not involved in the processing haloes.

            WARNING...There must be NO little bits of sky showing through gaps on the gear, flaps or isolated sky areas in the space formed where a wingtip crosses the line of the tailfin. If there are then they will get processed along with the aircraft and you'll get a "manipulation" rejection and be accused of changing skies.

            In actuality, there are so few pictures that fall into these requirements that I no longer use the inverse selection method. I only mention it here as a possibility.

            The sky is the major part of most of our pictures and is also the part that tends to show imperfections such as noise/grain, compression and haloes.
            What I do virtually 100% of the time is to follow roughly the following process....

            1. Adjust exposure.

            2. Level and crop.

            3. Check and adjust histogram.

            4. CREATE A BACKGROUND LAYER. I capitalise this because this is the bit that will be used later to delete the sky and any imperfections in it that may have been created in processing.

            5. Now I will use shadow/highlight to balance the highlights and dark tones. Go easy with it. Excessive use will easily spoil the whole thing. If I find that I need to use more than 10% shadow and 15% highlight then the picture probably isn't going to be good enough for upload. Move on to a bit of contrast adjustment if the image still seems flat and sharpen until the very first sharpening artefact (Jaggies) appear. I'd recommend setting USM to 100_0.2_0. ( EDIT.. CHANGED FROM 100_0.2_2 . I typed it wrong. ) Go back one step using Ctrl+Z and stop.

            Take a breath and look again. Are you happy so far with the contrast balance ? Don't worry about the sharpening, you can continue that in a minute. If you're happy then use the magic wand to select the sky. Be careful because if there are tones on the aircraft similar to those in the sky then the sky selection will "bleed" onto the aircraft. You may have to carefully rub out along the edge where the sky is bleeding into the aircraft. After each rub out select the sky again with the magic wand tool until it no longer selects any part of the aircraft.
            Those of you who photograph Air Canada and BMI aircraft are going to be doing a lot of this !!
            Once the magic wand selects only sky then delete it. You may have to repeat selection if there are cloud areas that don't select first time or use the eraser tool to rub them out. Erase/delete until the original sky in the first layer is visible. Any haloes, noise/grain etc. created in the sky during processing will now have been erased. Don't forget to erase/delete the sky areas in those little bits that are "landlocked" from wand selection. With prop driven aircraft and helicopters watch out also for odd looking "Mini Haloes" in the prop/rotor blur. Erase these with the eraser tool.

            This example picture has the potential problem areas circled in red.....

            I remember that when I processed this one the sky selection bled into the roof from the wing to nose. To cure this I used the polygonal lassoo tool to draw along the roof line, go up into the sky and back to the origin point to form a triangle. I then deleted the sky in that selected area and, when I went back to the magic wand, that part did not select.

            Once you've gone through all this deletion you can flatten the image and carry on with overall and selective sharpening. If you are going to use more overall sharpening then create another background layer, sharpen and delete the sky. No point in sharpening an area that you want as smooth as possible, is there ?

            And that's how I do it. There are other workflows out there to follow which are all just as good, some probably better.

            Hope this helps.
            Last edited by brianw999; 2008-06-17, 11:12.
            If it 'ain't broken........ Don't try to mend it !


            • #7
              Brilliant explanation Brian!!!

              That was what I was waiting for.
              I have to read this workflow a few more times to understand it at his best, but it wil help me in the future with that part of the editing process.

              Thank you very much.

              Never thought of writing a foto-editing workflow on your own?
              It would be a bestseller!




              • #8
                Wow, that's a fantastic explanation!! Thank you for posting


                • #9
                  Well Brian,

                  You've just uped your workload. With all these frustrated photographers now being able to post those pics they just couldn't adjust and so didn't bother posting.
                  By the way what tools ie. mouse or graphics tablet, do you use to get a steadyish hand when doing the free form laso. Cos at the moment I am working on my loungeroom carpet getting a sore bum trying to move a mouse on an uneven mat. Must get a table

                  Cheers and nice explanation



                  • #10
                    Thanks for your kind words folks. Just make sure you get it right or the other screeners will hang my nuts from this years' Christmas Tree !!

                    ...and I really should point out that skilful use of the curves tool is a better option.

                    Please note that I made an error with the recommended sharpening setting. It should read 100_0.2_0. I have corrected it in red in the original post.

                    Duncan.... Yes, you need a table....and a chair as well. ....and a cushion to sit on by the sound of it !!

                    I use a computer table with pullout keyboard shelf but any flat, smooth surface works. I don't use a mouse mat. I hold my wrist steady and move the mouse with a combination of finger and hand movement using the pad of flesh under the knuckle line to hold the mouse down to the table. Set the mouse speed so that, with the cursor in the centre of the screen, you can move the cursor to all four corners of the screen without having to move the heel of your hand or having the mouse hit or fall off an edge.
                    If you use a roller ball mouse make sure you keep it clean of sticky dirt. There are roughened "ball on the end of a stick" devices that are designed to clean the rollers in the mouse but I tend to use a not-too-sharp blade to scrape the rollers as well. Wash the ball in soap and water. For laser mice keep the base clean and use a smooth, same colour base area to move it over.

                    A carpet, Duncan, does not fall into this criteria !!!

                    Don't forget that you can always zoom in on those awkward little areas to work on them if you need to. It's the little details in processing that make for a smoother image in the end.
                    If it 'ain't broken........ Don't try to mend it !