The sky in stock photography
Sometimes, when taking a picture, the colour pallete of the sky does not help us to create a special, or at least an interesting image. I will be giving you some tips and tricks to help you escape this nightmare of a depolarized sky.
You can also try to increase the intensity of the blue color of the sky with the help of Cokin filters, a more affordable and practical solution, but take into account the small risk of losing some quality when magnifying to considerably large dimensions (larger then 1.5m on the largest side). The Cokin filters offer a fairly large range of Gradual Blue with a very good glass quality. You need to buy the holder and the ring and afterwards you can use any filter from the Cokin range.
Using the Cokin gradual filter requires a good knowledge of light reflections, as well as owning good quality lenses. (A small increase of granulation (noise) is felt in the aria exposed with the filter – undetectable for dimensions under 2000 px).
Another problem that must be taken into consideration is the usage of Cokin filters on wide angle and super wide angle lenses. These cause a strong vignetting effect that can totally ruin the image. The light obstruction created by the filter holder isn’t visible through the camera viewer, but when processing the film you will have an unpleasant surprise. It gives excellent results on 35 mm or bigger focal lengths lenses. Of course, you can buy special holders that have a very wide opening for the super wide angle lenses, but you will also have to change the range of filters you own. This is not a solution as they are pretty expensive.
Take extra care at circular polarization, you will obtain a maximum effect and a strong contrast only when the shooting direction is opposite to the sun’s position (in other words, you must have the sun at your back). When the angle created between the shooting object (plus sky), photographer and sun decreases under 180 degrees, the image will lose polarization. It is an unpleasant effect, because the sky doesn’t have a constant beauty in color and quality of the blue. If you don't own a circular or linear polarizer filter and the positioning of the sun doesn't result in a corect polarization, you can use a neutral filter; usually the best result is obtained with a second degree filter (it reduces the light in the filtered area with 2 aperture stops). If you don’t a have a camera that allows filter mounting, then keep in mind the following tricks for a bluer, more beautiful sky.
If you photograph mountain landscapes you have an advantage, offered by nature, which you must take. I am referring to the much clearer atmosphere and the increased visibility. Take your pictures, as much as possible, with the sun at your back. A sky polarization effect will be present even in the case of non professional cameras that do not have filters on. Another good advice would be to expose on the sky and not on the ground because the difference in lighting is quite big and the sky will be overexposed and all you will obtain will be a white or faintly blue sky. Do not be afraid that the faces of the persons you are shooting will not be properly illuminated,the front lighting will be giving you enough light.
Try to avoid photographing the sky at noontime, when the sun is exactly above your head; the polarization effect is lost and the sky will be very pale.
For those who love the sea more, it would be extremely indicated to have a circular polarizer for a perfect sky, but if you can’t mount it or buy it, then use these following tricks:
1. Photograph the sea and the sky only when the sun is in the opposite direction. The water reflection increases the white effect of the sky.
2. Put your hand above the lens to protect it from excessive light that flattens the image (be careful not to include it in your frame).
3. If you have sun glasses, then you’re lucky. You can put one of the glasses’ lenses in front of the camera. You will be surprised at the result.
4. Always expose on the sky closest to the water (this area usually has the most light)
If not even such a filter helps, you can create your own filter in PhotoShop, by following these steps:
1. Load the image you need to work on;
2. Create a new layer (position your working area on this layer);
3. Select form the toolbar - Gradient Tool;
4. Select from the toolbar - foreground color - white
5. Select from the toolbar - background color - a shade of blue that fits your image
6. Using the mouse cursor draw the direction and size of the color gradient
7. Select from the Layers working area the option Multiply;
8. Select the opacity of the layer which fits your image.
Some examples with Photoshop filter (without and with the filter applied):