Sigma 10-20mm f/4-5.6 EX DC HSM Lens Instruction Manual

1. Introduction

Thank you for purchasing the Sigma 10-20mm f/4-5.6 EX DC HSM ultra-wide angle zoom lens. This lens is designed specifically for digital SLR cameras with APS-C size image sensors, offering an expansive field of view ideal for landscape, architectural, and interior photography. Its advanced optical design and Hyper-Sonic Motor (HSM) ensure high performance and user convenience.

Key features include:

• HSM (Hyper-Sonic Motor): Provides fast, quiet, and precise autofocus, with full-time manual focus override.
• Aspherical Lens Elements: Three aspherical lens elements effectively correct distortion and spherical aberrations.
• SLD (Special Low Dispersion) Glass: Three SLD glass elements minimize chromatic aberration for superior image quality.
• Internal Focusing System: Maintains the overall lens length during focusing and allows for the convenient use of polarizing filters.

2. Setup

2.1 Attaching the Lens

1. Ensure both the camera and lens are powered off.
2. Remove the rear lens cap from the lens and the body cap from the camera.
3. Align the mounting index mark on the lens barrel with the corresponding mark on the camera body.
4. Insert the lens into the camera mount and turn it clockwise until it clicks into place. Do not force the lens.

2.2 Removing the Lens

1. Ensure the camera is powered off.
2. While pressing the lens release button on the camera body, turn the lens counter-clockwise until it stops.
3. Carefully remove the lens from the camera body.
4. Attach the rear lens cap to the lens and the body cap to the camera to protect the sensor and lens elements.

2.3 Attaching the Lens Hood

The included petal-type lens hood helps to block extraneous light and reduce flare. Align the red dot on the lens hood with the red dot on the front of the lens, then turn the hood clockwise until it locks into place. To remove, reverse the process.

Figure 1: The Sigma 10-20mm f/4-5.6 EX DC HSM lens. This image illustrates the general appearance of the lens, which attaches to compatible Sony Alpha DSLR camera bodies.

3. Operating the Lens

3.1 Focusing

This lens features a Hyper-Sonic Motor (HSM) for fast and quiet autofocus. It also allows for full-time manual focus override.

• Autofocus (AF): Set the AF/MF switch on your camera body to 'AF'. The lens will automatically focus when the shutter button is half-pressed.
• Manual Focus (MF): Set the AF/MF switch on your camera body to 'MF'. Rotate the focus ring on the lens barrel to adjust focus manually. Even in AF mode, you can fine-tune focus by rotating the focus ring after autofocus has been achieved.

3.2 Zooming

To change the focal length, rotate the zoom ring on the lens barrel. The lens offers a focal range from 10mm (ultra-wide) to 20mm (wide-angle). The aperture will vary between f/4 at 10mm and f/5.6 at 20mm.

3.3 Using Filters

The lens has a filter thread at the front. Due to its internal focusing system, the front element does not rotate, making it convenient to use polarizing filters or other special effect filters. Ensure the filter size matches the lens's filter thread diameter.

4. Maintenance

4.1 Cleaning the Lens

• Use a blower brush to remove dust and loose particles from the lens surfaces.
• For smudges or fingerprints, apply a small amount of lens cleaning solution to a clean microfiber cloth and gently wipe the lens in a circular motion from the center outwards.
• Never use abrasive materials or harsh chemicals.

4.2 Storage

• Always attach the front and rear lens caps when the lens is not in use.
• Store the lens in a cool, dry place, away from direct sunlight and extreme temperatures.
• If storing for extended periods, consider using a dehumidifying agent to prevent mold growth.

4.3 Handling Precautions

• Avoid exposing the lens to water or excessive humidity.
• Do not drop or subject the lens to strong impacts.
• Do not attempt to disassemble the lens, as this will void the warranty.

5. Troubleshooting

5.1 Autofocus Not Working

• Check if the AF/MF switch on your camera body is set to 'AF'.
• Ensure there is sufficient light and contrast in the scene for the autofocus system to operate effectively.
• Clean the electrical contacts on both the lens and the camera body with a clean, dry cloth.

5.2 Image Quality Issues (e.g., blurry images)

• Verify that the lens is securely attached to the camera body.
• Check your camera's shutter speed and aperture settings. A slow shutter speed can cause motion blur, and an incorrect aperture can lead to out-of-focus areas.
• Ensure the lens elements are clean and free from smudges or dust.
• If using manual focus, confirm that the subject is sharply focused.

5.3 Lens Not Recognized by Camera

• Remove the lens and reattach it, ensuring it clicks firmly into place.
• Clean the electrical contacts on both the lens and the camera body.
• Check your camera's firmware for updates, and ensure it is compatible with the lens.

6. Specifications

7. Warranty and Support

Sigma lenses typically come with a limited warranty covering manufacturing defects. Please refer to the warranty card included with your product or visit the official Sigma website for detailed warranty terms and conditions specific to your region.

For technical support, service, or inquiries regarding your Sigma 10-20mm f/4-5.6 EX DC HSM lens, please contact Sigma customer service through their official website or the authorized distributor in your country. Have your lens model number and purchase information ready when contacting support.