Sunday, February 15, 2009

Postprocessing for dummies

This is a short summary of what I usually do in terms of postprocessing. I consider myself still a dummy in this respect, so do not take offence by the title. Within a few minutes you can beef up your digital pictures without expensive software like Photoshop. Let's go through it.

1. Taking photographs
I am not going to address technical matters here, but I do want to point out a few learning points that I have picked up along the way:
- Always shoot photographs at the highest resolution that the camera will allow. The files are of couse bigger but with the prices of memory cards and DVD's going down, you need to work with the best material.
- Always take a number of pictures of the subject you want to photograph, from different angles. Behind the computer you can select the best one.
- Try to go for the right composition in general, but aim to shoot a larger photograph than you want. You can easily cut parts off, you cannot add parts you did not take.

2. Postprocessing (general)
I am using a simple and intuitive freeware programme for this, Picasa (see download link below). The postprocessing should aim at getting the best composition, with the desired contrasts and colours. I will not be discussing special postprocessing techniques here (Orton effect, HDR, Holga, Lomo) - maybe in another post later. My typical Picasa postprocessing, illustrated with the sample above, goes as follows:

Picasa step 1 - Basic fixes
I upload the shot I want to process in Picasa (#1 in the collage above). This is straight from the camera. First I select the desired crop to get the right composition. Things to look out for here are the rule of thirds, decentralizing the main subject, and getting rid of distractions. The background to the left is such a distraction and had to go. The resulting crop gets very close to square so I decided to go for a perfect square crop. I should have taken the original shot with more space around the model - the rule of thirds is difficult to apply now. Still, the decentralization in the crop is sufficient to make for a pleasing composition. Next I straightened the shot a notch. This is often not required, but if a horizon is included it is mandatory to check whether that is perfectly straight. Here I made sure that the vertical wall is 100% vertical by a very small correction. The third option I typically use on this page is the button auto contrast. In this case I did not like the result, so I reversed it. The shot after this first phase of postprocessing is included as #2 in the collage.

Picasa step 2 - Effects
Although the third page in Picasa, I prefer to do this as second. First I sharpen the picture a notch. In most cases this is a beneficial effect, but sometimes you will decide to reverse it. Secondly, I use the saturation button, again a notch. It is easy to overdo it. An alternative option at this stage is to go for black and white or sepia. When colours are not very interesting, this is an attractive alternative. Also when shapes are dominating, a black and white rendition can be a striking version. The shot after this first phase of postprocessing is included as #3 in the collage.

Picasa step 3 - Tuning
Typically I will increase Fill lights and Highlights a notch and Shadows a bit more. This is very much trial and error until you have the end result you are satisified with. Once you reach that stage, the shot is finished and ready for saving. The shot after this first phase of postprocessing is included as #4 in the collage.

The link below leads you to the Picasa download page.

link