Flash guide number

Concepts in Photography

Flash

Light is one of the most important components in photography. It’s not easy, however, to have an enough amount of light anytime and anywhere. Making use of a ﬂash allows you to optimize light settings and create a variety of effects.

Flash, also known as strobe or speed light, helps to create adequate exposure in low-light conditions. It is also useful in light-abundant situations. For example, ﬂash can be used in compensating the exposure of a subject’s shadow or capturing clearly both the subject and the background in backlit conditions.

Before correction

After correction

The model number of a ﬂash refers to the ﬂash’s power, and the maximum amount of light created is represented by a value known as a “guide number.” The bigger the guide number, the more light is emitted from the ﬂash. The guide number is achieved by multiplying the distance from the ﬂash to the subject and the aperture value when the ISO sensitivity is set to 100.

Guide number = Flash to Subject Distance X Aperture value

Aperture value = Guide number / Flash to Subject Distance

Flash to Subject Distance = Guide number / Aperture value

Therefore, if you know the guide number of a ﬂash, you can estimate an optimum ﬂash to subject distance when setting the ﬂash manually. For example, if a ﬂash has a guide number of GN 20 and is 4 meters away from the subject, the optimal aperture value is F 5.0.

NX100 specifications

The Samsung NX100, launched in 2010, marked a significant entry into the mirrorless camera market, showcasing the brand’s commitment to innovation and style in photography. This compact system camera combined versatility with advanced technology, appealing to both amateur and professional photographers alike.

One of the main features of the NX100 is its 14.6-megapixel APS-C CMOS sensor, which delivers stunning image quality and excellent low-light performance. This sensor size is comparable to that found in many DSLRs, allowing for greater depth of field and better control over exposure. The impressive image resolution enables photographers to capture intricate details without sacrificing clarity, making it ideal for large prints.

In terms of design, the NX100 boasts a sleek and stylish body that is both lightweight and compact, making it easily portable for photography on the go. The camera features a detachable lens system, compatible with Samsung's NX mount lenses, allowing users to tailor their equipment to the specific needs of their shoots. The standard 20-50mm lens provides great versatility for everyday photography.

The NX100 incorporates a Hybrid AF system, combining contrast detection and phase detection to achieve fast and accurate focus, an essential feature for capturing moving subjects. Furthermore, the camera supports continuous shooting at 3 frames per second, enabling users to capture action sequences with ease.

Another notable characteristic of the NX100 is its 3-inch AMOLED display, which offers vibrant colors and excellent viewing angles. This display is crucial for composing shots and reviewing images in varying lighting conditions. Additionally, the camera includes manual control options, giving experienced photographers the flexibility to adjust settings such as shutter speed and aperture, while also providing automatic modes for those looking for ease of use.

The camera's integrated Smart Filter effects allow for creative expression directly in-camera, offering options like Soft Focus, Vignette, and Miniature effects. These filters enhance the creative potential and make experimentation more accessible for users.

Enhanced connectivity is also a key feature, as the NX100 includes Samsung's i-Function technology, allowing users to adjust settings directly from the lens using designated buttons for a seamless shooting experience. The ability to connect via USB and HDMI provides additional convenience for sharing images and videos directly to external devices.

In summary, the Samsung NX100 reflects a blend of sophisticated imaging technology and user-friendly design. Its APS-C sensor, compact build, and innovative features create an appealing option for anyone looking to dive into the world of photography or expand their creative toolkit.

Samsung NX100 user manual Flash guide number

Models: NX100

Flash

Flash guide number

NX100 specifications