To get the best results using a strobe, you must go beyond the limitations of a built-in flash to the flexibility and power of an external strobe. A built-in flash is usually too weak to illuminate your subject properly. It's likely to add backscatter to your photo and because it's fixed in place, it might not clear add-on lenses, throwing a shadow on your subject.
There are many reasons why an external strobe is best:
1. It's more powerful so you can illuminate your subject from further away.
2. It's on an adjustable arm that lets you position the strobe where you want it for exactly the lighting effect you want.
3. You can avoid backscatter by moving the strobe away from the lens.
4. You can adjust light intensity manually or automatically (via DS-TTL on the YS-110 strobe) to get precisely the amount of light you need..





Using your strobe from different angles to your subject can produce dramatically different results. Below are two examples. The first example illustrates top lighting (illuminating the subject from above) using a single strobe. |

The next example illustrates side lighting (illuminating the subject from the side) with a single strobe. |
A single strobe will easily cover a full frame when you're shooting macro photos. If you're shooting from the side, though, a single strobe throws hard black shadows on the side opposite the light. You can eliminate these shadows by using two strobes. |

Watch a movie of two-strobe lighting in action, from touching bottom to shooting. |
The eyes of a fish are a very important part of underwater photography. Shooting with a strobe located next to or above the lens makes most fish eyes appear black. Shooting with one or more strobes located to the side may, depending on the type of fish, add a gleam of lightning to the eyes. |
The first time you add an external strobe to your housing and try it out, it may take a little while to get good results. Take your time when shooting to set your strobe up in the right position. Is it at a good angle from the subject? Does it face the subject? |
Each SEA&SEA external strobe comes with a diffuser, a milky plastic attachment that attaches to the front of the strobe. A diffuser drops the strobe's light level by one full F stop and gently spreads the light to provide even illumination for a scene. You may not want to use a diffuser if you're trying to create dramatic colors and contrast, but it can really help for pictures with a delicate, gentle feel. It's very useful in extreme macro photography where a strobe can overwhelm tiny subjects. |