With the ever growing availability of digital cameras and the availability of reasonably priced underwater housings for these cameras more and more divers decide to start taking pictures under water. Underwater photography is in principle not different from photography on land but the circumstances under water make that the results are not what is expected. Often the idea is that this is the best that this camera can deliver. That is definitely not true. With a basic point & shoot camera without an external strobe it is possible to get better results than the green images that most divers bring to shore.
The pictures in this article are made with a simple camera, the Sealife DC500 in an underwater housing that is sold together with that camera and without using an external flash. The only setting this camera has is automatic exposure. There is a special setting for underwater pictures but that setting is not used because I am not happy with the results of this custom setting.
What are the circumstances that make taking pictures under water so difficult?
- You are not on firm ground. Instead you are drifting in the water.
- The deeper you are the less color is left. Water acts as a filter and the first color to go is red. That is the reason your pictures look greenish.
- Water is less transparent than air.
The green pictures you get are a truthful representation of the reality under water even though you were seeing more color than is visible in the picture. That is because your brain compensates for the lack of red and other colors.
The above picture is impacted by all these factors. This picture is made at a depth of 10 meters on a sunny day. The picture is not sharp (1), there is a lack of color (2) and the contrast is low (3).
What can you do to get a better result??
Stability in the water
Before you start taking pictures under water your buoyancy control should be very good. Taking a camera with you under water asks a lot of your attention. If your buoyancy is not sufficiently under control the camera is just too much. If your buoyancy is ok then the first hurdle is taken. But that is still not sufficient as the pictures shows. The picture is not sharp because there was insufficient light for a short exposure and that resulted in blurring when I pushed the trigger. To avoid that there are some things you can do:
- You can increase the sensitivity. This camera was on automatic which means that the camera decides what the best combination is of sensitivity and exposure. A disadvantage is that the maximum sensitivity of this camera is 200 ASA which is just a factor 2 more sensitive than the standard 100 ASA. As a consequence the exposure time is increased (slower) when there is insufficient available light. But that was not the problem in this case. The exposure was 1/42 sec, the opening was F/2.8 and the sensitivity was 50 ASA.
- You have to push the trigger very carefully. That is what I apparently didn't do. It should be possible to get a sharp picture at 1/42 sec although this requires some experience.
This camera uses a push button as trigger. A lever would be better because you need less pressure to release the shutter which means that there is less risk to move the camera when releasing the trigger. This is something to pay attention to when buying your next camera and underwater housing.
Loss of color under water
The camera doesn't know that you are under water. So the camera doesn't correct for the color loss automatically. That is the reason why cameras have a special option for under water. Because the loss of color is dependent of the depth such an option works best at the depth the vendor of the camera has decided on. And that is exactly the reason why I am not happy with such a custom option.
Luckily lots of cameras have an option to set the color balance manually. The Sealife DC500 has such an option and I have used this option to take a second picture of the same soft coral as in the first picture.
This time I was more careful to push the trigger button. As a consequence this picture is sharp. Apparently there was a bit more light available because the exposure time is now 1/52 sec.
All the other settings are the same.
Setting the color balance manually is done by pointing the camera at a pre-determined color (white of gray) and then pushing a button. In this way the camera is told which color should be white or gray. If your camera has an LCD-panel the image will show too much red because your brain still corrects although you camera already made a correction. As you can see this picture is already much better. The green is gone and the picture has a more natural color although the picture as a whole still lacks contrast.
In my experience setting a custom white balance gives acceptable results till about 15 meters in clear water. From 10 to 15 meters more and more correction is necessary in the post-processing. At depths of 15 meter and more there is so little color that it is almost impossible to correct this in the post-processing. Keep this in mind for your next dive. Stay shallow; then you will have more available light and more color.
Lower transparency under water
First a little bit of explanation. Before the rise of the digital camera you had to take your film to a photo shop for development and printing. That this photo shop did a lot more to get good results was not important to you. But nowadays things have changed. Pressing the button is still the same but now the picture is instantly developed. So the only thing that is missing is printing (or publishing on the web). If this is all we do we skip the steps that previously were done by the photo shop but are surprised that the result is not optimal. The younger generation grew up with the digital camera so they don't have a reference from the film period. The problem is that the photo shop did additional work to get a good result and it is this work that we have to do ourselves now. Developing the digital image is not necessary unless you take RAW-pictures. But some corrections are still necessary to get a result that corresponds to what you aimed at when you took the picture.
With almost every digital camera comes an"editing" program. Editing programs can also be bought separately. Photoshop CS is such a well-known editing program. Photoshop Elements is a simpler version of this program and that is sometimes included with the camera. Photoshop CS is a far more expensive commercial version. But expensive or cheap all programs have at least the option to correct contrast and color.
The above image is processed in Photoshop CS with the function "Autotone". That is function that with one click corrects contrast and color. The result is far better than the original greenish picture. This is how I remember the situation under water.
Because of the lower transparency a good tip is to get as close to the object as possible. It is for that reason that there is almost no space around the main object in the above picture. Most beginning photographers tend to take pictures from a distance and to zoom in to get the object better framed in the picture. This zooming in results indeed in the object filling the frame, but the amount of water between camera and object is more than is necessary. Try to "zoom in" by moving towards the object. Keep the camera at wide angle (fully zoomed out) and move towards the object till it fills the frame. Then the amount of water between object and camera is as little as possible.
If you don't have a camera with a manual exposure setting and if you don't have an external flash, in other words if you have a rather basic point and shoot camera then keep the following points in mind to get a better result:
- Only take a camera under water if your buoyancy is sufficiently under control.
- Release the trigger as careful as possible to avoid blur because of camera movement.
- Use the custom white balance function of your camera and repeat this if you change depth.
- Always process your pictures in a photo-editing program. Use the program that came with the camera, buy a commercial package or search the Internet for an Open Source free alternative. Correct exposure, contrast and color if needed.