In my last post I showed some of the interesting effects that can be made with HDR. I tried to make it clear that the technique can also be used to create enhanced but realistic photos. As I explained, HDR is used to add additional light information to the photo which allows these extreme effects to be created. To demonstrate a more realistic processing I'm going to use the same starting image as last time:
As can be seen in the original image the sky is overexposed while the shadows are very dark. While this can be edited in any decent photo software, the result will look similar to the right image. This edited image shows far more detail in the shadows and some more in the sky. This edit was only made possible due to the camera saving into a RAW format.
The final edit shows the same level of improvement over the original photo (in terms of detail) as the dramatic edits of the last post. The same type of processing is applied but less strongly allowing the photo to retain a more natural feel.
HDR stands for High Dynamic Range. HDR basically refers to an image having a range of brightnesses greater than the camera is capable of capturing, in a single photo. The way these are taken is with a series of exposures which with computer trickery are combined into a 32bit picture file. These cannot be displayed on normal computer screens/TVs so are 'photoshopped' back to a regular 16 or 8bit file. While this can give realistic results, it also allows for some wacky effects to be created.
I'm not going to go into the details on how to create these effects but will provide some links to tutorials at the bottom. I wanted to test the benefit of multiple exposure HDR over single exposure pseudo-HDR (the cheat method*). Additionally, I wanted to test how many exposures are needed for the best result. The three examples below show some of the effects HDR photography can lead to:
Single Vs Multiple Exposure HDR
There are times when either are appropriate but traditionally, the 'best' results will always come from a multiple exposure HDR. If there is movement in the scene you will get ghosting, which is the name given to the strange grey halos found around the moving objects (this can include plants/leaves moving in the wind). Software can reduce ghosting and in certain cases, remove it completely but a detailed tree scene on a windy day is going to have too much movement. *In these cases you can try single exposure HDR; this is only effective if you camera saves in RAW mode. Continue reading
Following on from Playing With Light 1, I decided to take more pictures to highlight the difference playing with part 2 and 3 makes to your photos.
The background to this photo wasn't particularly messy to begin with, a range of greys and blacks. The addition of the pink paper makes the scene feel more isolated.
The badger scene is a good example of how different types of flash effect the final photo. In natural light, the photo feels a little washed out as the camera increased exposure to reveal the darker areas (this clearly could be corrected by flicking onto manual). The shadows help to show the shapes of the badgers.
With the camera flash you lose a lot of the natural shadows that helped show the shapes and sizes of the objects. At the same time you are gaining dark shadows directly behind the objects which I find reduces the contrast with the background.
Finally, the off camera flash also removes the natural shadows but creates equally helpful new ones which help show the sizes/shapes of objects. The flash throws enough new light on the scene that the camera exposure is reduced allowing for easier handheld shots and more vivid colours.
This fly example simply reinforces the points I've just made. Natural light has good shadows but lacks pop. The camera flash has plenty of contrast and good colours but the new shadows on the background make the edges harder to see. The external flash is clear and has the benefit of a new dramatic shadow thanks to the light coming from a low angle.
Below are a few of the final images from my mini, playing with light, photo sessions (on Flickr):
Photography is all about catching light (literally) and yet I have never played about with lighting in any depth before. I've played with every setting on all my cameras but that is only part of the story.
In my opinion, there are three parts to taking pictures:
- The light before the subject
- The subject
- The light after the subject (to the camera)
So with a typical outdoor photo that might include:
- Light from the sun
- Hits a landscape/person and is reflected
- Position the camera to catch the light
Where am I going with this?
I think when anyone takes a picture they are playing with part 3. By playing with camera settings etc you enable yourself to capture the light more effectively.
Interacting with the subject before taking the picture is playing with part 2. This might consist of telling someone to smile or describing a precise pose. Alternatively, it might be cleaning/moving something to get a better photo. So part 2 again isn't necessarily demanding.
If you are outside you would normally use the sun to light up your subject or if it's dark/inside you may use flash. Since getting an external flash for my DSLR I have been able to tinker with part 1 by bouncing light off the ceiling/walls onto the subject. Compare this to a photo studio where there are carefully positioned lights everywhere! Playing with part 1 is a great way to change the look/feel of photos.
Mini comparison of flash lighting
The photo is of a peacock feather with sunlight coming from the near right. The picture without flash lacks contrast due to the bright background and lack of shadows.
The camera flash and external flash with diffuser look best as they have added enough shadow for increased contrast and enhanced colour. The external flash is raised from the camera lens which makes the light non-centred, noticeable without the diffuser at this short range.
Although bouncing the flash off the ceiling or wall normally adds improved shadows, this is not always ideal especially due to the feather leaning forward casting itself in shadow!
The bottom right image (where the flash is not attached to the camera) adds a strong light from the bottom left which completely changes the look of the photo. Although in this case it adds too much shadowing, it does change the colours from all the other examples.
The following photos were taken with the same off camera flash position:
The major benefit I noticed with the off camera flash is that I can get close to the subject without the light changing or casting my own shadow onto it (often the case with sun lit macro shots). The major downside is that I kept blinding myself with the flash... #amateur.