In the previous post I described how to isolate an image on white. This time I will mention some easy yet powerful Photoshop techniques which have helped me to get more out of my photos. I am not going into details because there is an enormous amount of information already available on the internet about all kinds of Photoshop tricks and this is not my speciality. I am just using some basic Photoshop techniques which have helped me but I definitely do not consider myself an expert in this field. You are welcome to recommend additional tricks which might help me and others.
The Levels tool (Ctrl+L) has been very valuable for me. I apply it to most of my photos. It shows you the histogram (distribution of brightness) of the picture and allows to make some adjustments. If the histogram does not extend from one end to another, you could consider moving the triangular sliders below closer to the edge of the histogram. By doing that you will define new black and white points and stretch the histogram. Moving black point has the strongest and most desired effect in my opinion because it will make foggy images much clearer. Do not overdo it because defining new black and white points means that you will clip some dark and bright tones. You can also use midtone slider (gray triangle in the middle) to compress either dark or bright midtones but I do not find it as valuable as black and white point sliders.
Picture of an agate breccia before and after the modifications (levels, white balance, Lab colors, some outline smoothing) described in this post.
In the previous post I mentioned that I prefer to use a sheet of white paper to have a white reference surface. There are many other ways to set the correct white balance. I use gray card when indoors and outdoors I just select the appropriate predefined white balance settings from the menu and sometimes take control shots of a gray card if the conditions are somewhat more tricky (clouds or shade). Camera usually does adequate job outside. These are indoor conditions with artificial lighting that usually cause problems. If you are not sure what you are doing, simply select auto white balance (AWB) and you should be fine while outdoors. But what about the white sheet of paper? How to use it to set the white balance? Photoshop offers a very convenient tool for it which is named Curves. Press Ctrl+M to access it and choose a pipette below (righternmost of the three) which is used to take a sample from image that should be white. So just click with it on a surface that should be white (your piece of paper) and all the colors in the image will be modified accordingly. This tool usually performs quite well but pay attention to the area you click on because white paper is not absolutely white. Choose the brightest area and try again in another place if the result is not what you expected.
Photos with vivid colors always draw more attention than the ones with drab colors. Photoshop has a Saturation tool but I do not like it because it also boosts luminance, not only colors. You can give a very little boost to colors without making them unnatural. There is another and much better way to add colors to your images. To do that convert your image to Lab mode (Image -> Mode -> Lab Color). Now pay attention to Channels window (next to Layers). There are three channels: Lightness, a, b. We ignore lightness and work on with a and b. Select a and press Ctrl+L to open Levels tool. Now we can see the histogram we are already familiar with. To boost color you should move both black and white triangle inward by an equal amount. I prefer to write the values instead of 0 and 255 that are already there (10 and 245 for example). It must be equal amount from both sides, otherwise you not only boost but also modify the colors which we do not want. 10…25 from both sides is sufficient to get a noticeable effect. Repeat the same with b. Now check the result and compare it with the original. If you are not satisfied, go back and do it again with other values. Note that this modification suits well with some photos but definitely not with all of them. I apply it when my samples are colorful (bright green, red, and blue tones) but avoid it when just dark and light tones dominate because in the latter case this technique tends to amplify tones that really are not there in the first place to any noticeable extent. It only makes your almost black and white rocks or whatever you are photographing yellowish. Do not forget to go back to the RGB mode (Image -> Mode -> RGB Color) after you are done with this.
Shadows and highlights
Sometimes there is too much contrast in our photos. Dark shades and washed out reflective areas. Such photos are often beyond repair but if they need just a slight modification then you could try Image -> Adjustments -> Shadow/Highlights. It helps to brighten up shady areas and darken washed out areas. It is quite amazing tool but can be used only very modestly because shady areas become quickly very noisy and photos obtain somewhat unnatural look. “Noisy” means that there are lots of colorful pixels that really should not be there because they do not represent the real colors of the object we are photographing. Be careful with this tool and only use it when really needed. The same is true with what ever we do in Photoshop. It pays to be modest.
I described in the previous post how I isolate an object on an image on white. It is often needed to pay attention to the outline after doing it because it may be too sharp and becomes disturbingly noticeable. To make it look better, zoom in and choose Blur tool (R) with a small brush size (10-15 pixels) and wipe over the sharpest parts of the outline. After you have done that there is much smaller chance that someone will complain about unnatural outlines of your cut-out objects. Here it is also very important to have a white background if you intend to isolate your image on white. If it is not then you are bound to waste lots of time trying to make the outline look natural.
I have one more recommendation. If you are using SLR then you can set your camera to record both JPG and RAW formats. Do it because RAW gives you much more flexibility later. You can easily modify white balance, correct exposure, etc. If you have only JPG then you are very restricted in your options. Every time you enhance your photo in one area, you have to give in in another. The only drawback of RAW is its file size but nowadays it is not a real problem anymore.
If you are still reading then perhaps you are also interested in my macro photo tutorial: How to take good macro photos.