Week 1 – Initial Exposure Techniques
Exercise 1 – Minor adjustments to the original file
Excercise 2 – Understanding the Histogram
This is the original Image converted to Grayscale. The histogram tells us that the image is primarily made up of mid to dark tones, where as in contrast there is few light tones.
Excercise 3 – Adjusting the image with levels
This is a screenshot of the histogram after adjustment with levels. I decided to clip the dark tones on the histogram, this helped achieve a better all round exposure and contrast to the shadows, dark and mid tones in the image. I chose to leave the highlights although they lack detail as I felt they worked well as they were.
This image is the final product after adjustments were made using levels. Now I feel the image has gained a greater all round contrast whilst maintaining the original highlights which I felt were aesthetically pleasing.
Excercise 4 – Adjusting the histogram with curves
This time I repeated the process of editing using curves with the colour image. The process remains the same but more attention is payed to the individual histograms for the red, green, and blue channels. In this instance there is a fairly even distribution of tones between the red, green and blue channels. All three are mainly lacking detail in mid to dark tones.
Here is how the histogram looks after adjustments to the three channels with curves. All three have been clipped in shadows and darks to recover lack of information.
Excercise 5 – Targeting saturation levels
Image > Adjustments > Hue/Saturation
Hue/Saturation can be used to increase or decrease the saturation of specific hues within the image. This panel is often used to make a dominant color appear more vibrant in an image, but it is hard to notice if the image is not being viewed at 100 percent. Even then, sometimes it is easier to see the results of this image adjustment in the final print.
In this case I specifically worked onthe greens in the image. I incresed the saturation to create a more vibrant green but also reduced lightness to maintain the tone of the surrounding shadows. I also added a slight hue to the image. The drop down menu can also be used to individual edit Reds, Yellows, Greens, Cyans, Blues, Magentas.
Exercise 6- Sharpening the image
Unsharp Mask is a filter that is commonly used to compensate for this loss. This filter finds edges by looking for contrast and increases the contrast of those pixels, while leaving the flat areas untouched. The resulting image looks sharper, without introducing noise into the image.
The guiding relationship is between the settings in this dialog box and file size. The larger the file size, the larger you will set the threshold, radius and amount. With smaller file sizes (anything less than 30 megabytes) you will probably leave the threshold at 0, the radius lower than 1.0, and adjust the percentage by eye between 20 and 250 percent. Too much contrast will create visible halos at every edge. Applying this filter should produce a minor modification.
Here is a preview of the sharpening settings I decided upon after some experimentation.