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- 1 - Workflow for editing your aviation photos V1.1 – Jan. 2010 - 2 - Content

- 1 - Workflow for editing your aviation photos V1.1 – Jan. 2010 - 2 - Content Workflow for editing your aviation photos V1.1 – Jan. 2010 ....................................................1 1. Basics...................................................................................................................................3 2. Editing ..................................................................................................................................3 2.1 Correcting the horizon.....................................................................................................3 2.2 Cropping .........................................................................................................................5 2.3 Adjusting the levels .........................................................................................................7 2.3.1 Understanding different types of histograms ..........................................................10 2.3.2 What does that mean for my editing? .....................................................................15 2.4 working with curves.......................................................................................................17 2.4.1 Adjusting curves directly in the photo .....................................................................20 2.5 adjusting colour.............................................................................................................21 2.6 brightness and contrast.................................................................................................22 2.7 done with the first adjustments .....................................................................................23 2.8 reduce noise .................................................................................................................23 2.9 Resize ...........................................................................................................................24 2.10 remove dust spots.......................................................................................................25 2.11 basic sharpening.........................................................................................................28 2.12 advanced sharpening..................................................................................................30 2.12.1 Advanced sharpening technique to reduce noise in the sky.................................31 2.13 Saving the photo for upload ........................................................................................33 3. Editing Tricks......................................................................................................................34 3.1 Shadow and Highlight tool ............................................................................................34 3.2 Lens Correction filter.....................................................................................................35 3.3 Useful Photoshop shortcuts ..........................................................................................36 4. Setting up the camera for easier editing.............................................................................36 4.1 File Format....................................................................................................................36 4.2 Important for shooting JPG ...........................................................................................37 - 3 - 1. Basics I will use Photoshop CS2 for the guide; any other version of Photoshop or other photo editing programs should be able to do the same. I have added some information for Photoshop CS4 as well. 2. Editing As an example I will use one of my photos. I choose one of the typical spotting shot with many flaws, but a quality that should be easily possible for you, if you have a decent control and knowledge of your camera and its settings. 2.1 Correcting the horizon The first step to do is to correct the horizon. For that we will use a vertical reference in the photo, like the edge of a tall building. Masts and lamp posts are generally not good reference points, as they can lean to one side in reality quite often. The runway itself might be a good - 4 - reference, but on some airports it slopes, so it is not suitable then. Your main reference however should be vertical structures. For levelling the photo I use the measure tool and draw a line along the side of a vertical structure. It is a good idea to set the background colour to something colourful before you start with levelling the photo. Using the measure tool See that it has been selected. Now draw a line that matches a vertical reference object. Then you go to Image -> Rotate Canvas -> Arbitrary This opens a box, in which the amount of rotation is already entered based on your use of the measure tool. Click ok. The photos is rotated as needed, you know should check if the result is balanced. Are the verticals in the centre really vertical? Do the verticals on both sides look good? If you used a wide angle lens, both sides should show some difference to being fully vertical, the centre must be correct. Finally check with available horizontal reference objects. If everything looks well balanced, you are done, if not repeat the steps for levelling the photo until it is perfect. After that your screen should look like that. - 5 - 2.2 Cropping Now it is time to crop your photo down to the allowed sizes of the website. Usually a crop ratio of between 4:3 and 3:2 is acceptable. In pixel this is: Pixels wide Pixels high (4:3) Pixels high (3:2) 800 600 533 1024 768 683 1280 960 853 1600 1200 1067 I prefer using 3:2 crop for typical side on shots like the example. You click on the crop tool and enter 3 cm and 2 cm into the X and Y fields- Do not enter anything into the resolution box. Another option is to enter the pixel size you want into the tool settings. So you should enter 1280px and 960px for example. - 6 - Crop tool selected and settings for a 3:2 crop entered Pull up the crop box and try to keep the centre in the middle of the aircraft, typical on the height of the window line. crop tool in use – aircraft centred. Be careful that you do not have parts of the plain background from the rotation in the crop. At this point selecting a colourful background colour (as described in 2.1) pays off. - 7 - 2.3 Adjusting the levels The next part of the editing process is to work on the perfect exposure of the photo. For that you need to create an adjustment layer You do this by going to your layers toolbox (F7 opens it) and the clicking on the black and white circle in the lower middle of the toolbox. (Create fill or adjustment layer). How to create an adjustment layer for levels Then you adjust the histogram until it looks like this. - 8 - Adjusting levels In the example the exposure was pretty ok, out of camera, so there was only a little work to be done, but you might experience other cases in which you have to adjust the histogram much more. It might look like that: Then you have a photo that lacks contrast. You must then move the slider for the black point and the white point to the edges of the curve in the histogram. This can be easily fixed and you have not lost any information in the photo, you just did not use the whole dynamic range of your camera while shooting the photo. - 9 - This is more or less the same basic problem. No black parts have been recorded. Simply move the black slider in PS to where the histogram starts. The image will look bright and lacking contrast. In that case the photo will look a little dark. Just move the white slider to the correct position and it will look better. Much worse however is a histogram that looks like that: Here you have too much (too hard) contrast. Information has been lost. Some parts have been recorded as pure black; others as pure white, in both fine details have been lost. This is not possible to recover in editing, so it is something you want to check on your camera while shooting. If the histogram in camera looks like that, turn down then contrast in the camera settings. General advice: check the histogram in camera regularly If the histogram is clipped at the left or right side you need to adjust your exposure. (+ if it is clipped on the left, - if it is clipped on the right) - 10 - 2.3.1 Understanding different types of histograms Most modern cameras can display a luminosity histogram and a RGB histogram. The RGB is most often displayed with all 3 channels given in separate diagrams. Photoshop is also able to display different types of histograms. I will explain how to do that in CS4. Go to the “View” pull down menu and activate “Histogram”. Our example should then look like this. You can see the histogram as the second info area from the top. The default setting is “RGB”. This histogram combined the values from the Red, Green and Blue channel into one single graph. - 11 - RGB histogram The other very useful type is the luminosity histogram. It disregards colour and just measures the brightness of the pixels. Luminosity histogram Simply said that is the histogram you would see in the RGB version, if you would convert your photo to B+W. (you can try it to see the effect) - 12 - Colours histogram The third useful histogram version is the “Colors” histogram. There you can see the distribution of colours. But this is only interesting in some special cases, or to get an idea in which part of the photo your white balance might be off. In editing we use the histogram in the levels function to correct the exposure and the contrast. But as shown in the previous section, different types of histograms show different information. If we take a look at the RGB combined histogram and the luminosity histogram shown in the previous part, we see little difference. RGB histogram on the left and luminosity on the right But if we look closely we see that the graphs do not really match. The peaks are different. So let us take a look at the histograms of the individual colour channels. - 13 - Red, green, blue and RGB We can see that the first 2 peaks from the left are mainly created by the blue channel. The third peak is mainly green. While only the highest peak is a combination of high peaks in all 3 channels. The individual colour channels show black on the left and 100% red, green or blue on the right. A pure white in the RBG is the addition of pure red, green and blue. To make it easier to understand we add a 100% red rectangle to the otherwise unchanged photo. Now let us take look at the RGB histogram again. - 14 - We can see that on the uploads/Geographie/ editing-guide.pdf