Meike MK-N-AF1-A Macro Extension Tube Adapter for Nikon DSLR Cameras

1. Introduction

The Meike MK-N-AF1-A Macro Extension Tube Adapter set is designed for Nikon DSLR cameras and compatible lenses. This accessory allows for macro photography by increasing the distance between your camera's lens and the sensor, enabling closer focusing distances and greater magnification without altering the optical quality of your lens. The set includes three tubes of varying lengths (12mm, 20mm, and 36mm) that can be used individually or in combination to achieve different magnification ratios.

Image: The Meike MK-N-AF1-A Macro Extension Tube set, featuring three distinct tubes.

2. Product Features

• Electronic Contacts: Equipped with electronic contacts to maintain autofocus (AF) and through-the-lens (TTL) metering functionality between the camera body and lens.
• Variable Magnification: Consists of 12mm, 20mm, and 36mm tubes that can be used individually or combined for seven different magnification possibilities.
• Durable Construction: Features engineering plastics for the main body and metal bayonet mounts for secure attachment.
• Enhanced Macro Capability: Moves the lens farther from the sensor, allowing for closer focus and increased magnification for macro shooting.

Image: Key features of the Meike Macro Extension Tube, highlighting its design and functionality.

3. Compatibility

This extension tube set is compatible with Nikon DSLR cameras and a wide range of Nikon SLR and Nikkor AF, AF-S, D, G, and VR series lenses. Compatible camera models include, but are not limited to:

• Nikon D80, D90, D300, D300S, D600, D800
• Nikon D3100, D3200, D5000, D5100, D5200
• Nikon D7000, D7100
• Other Nikon D-series cameras (D40, D40x, D50, D60, D70, D100, D200, D3, D3S, D700)

Ensure your camera and lens are compatible with Nikon F-mount accessories that support electronic communication.

4. Components

The Meike MK-N-AF1-A set includes the following components:

• 1x 12mm Extension Tube
• 1x 20mm Extension Tube
• 1x 36mm Extension Tube

Image: Front view of the 12mm, 20mm, and 36mm extension tubes.

Image: Rear view of the 12mm, 20mm, and 36mm extension tubes.

5. Setup and Installation

To attach the extension tubes to your camera and lens:

1. Ensure your camera is powered off.
2. Remove the lens from your camera body.
3. Select the desired extension tube(s). You can use a single tube (12mm, 20mm, or 36mm) or combine them (e.g., 12mm + 20mm, 12mm + 36mm, 20mm + 36mm, or all three).
4. Attach the first extension tube (or the combination of tubes) to your camera body by aligning the red or white dot on the tube with the corresponding mark on the camera body. Rotate the tube clockwise until it clicks into place.
5. Attach your lens to the front of the extension tube(s) by aligning the marks and rotating clockwise until it clicks into place.
6. Ensure all connections are secure.

To detach, press the lens release button on the camera body (or on the extension tube if detaching from another tube) and rotate counter-clockwise.

Image: Assembly diagram illustrating the connection of extension tubes between a Nikon DSLR and lens.

6. Operating Instructions

Using extension tubes for macro photography requires understanding their effect on focus and exposure.

6.1. Autofocus (AF) and Exposure (AE)

• The Meike MK-N-AF1-A tubes maintain electronic communication, allowing for autofocus and automatic exposure with compatible lenses.
• When using a single extension tube (12mm, 20mm, or 36mm), autofocus generally functions well.
• When combining multiple tubes, especially all three (12mm + 20mm + 36mm = 66mm), autofocus performance may become less reliable or slower due to the significantly reduced minimum focusing distance and light loss. In such cases, manual focus is often recommended for precise results and to protect the lens's autofocus motor.
• Through-the-lens (TTL) metering for automatic exposure (AE) will function correctly, except when combined with an electronic flash AE unit.

6.2. Magnification and Working Distance

Extension tubes increase magnification by moving the lens further from the camera's sensor. This also reduces the minimum focusing distance, allowing you to get closer to your subject. The magnification ratio becomes smaller as the focal length of the master lens increases and larger as the focal length decreases. Conversely, the working distance (distance from the front of the lens to the subject) becomes further away with longer focal length lenses and closer with shorter focal length lenses.

6.3. Depth of Field and Camera Shake

• In close-up shooting with extension tubes, the depth of field becomes very shallow. It is advisable to stop down the lens (use a higher f-number) to increase the depth of field.
• As image magnification increases, camera shake becomes more pronounced. Using a tripod and a cable release (or remote shutter) is highly recommended to ensure sharp images.

7. Magnification Ratios and Exposure Factors (50mm Standard Lens)

The following table provides approximate magnification ratios, field coverage, working distances, and exposure factors when using a 50mm standard lens with various extension tube configurations. These values are for reference and may vary slightly depending on your specific lens.

Table: Magnification ratios and exposure factors for a 50mm standard lens with various extension tube combinations.

Image: Visual representation of the magnification and exposure table.

8. Maintenance

• Cleaning: Use a soft, dry cloth to clean the exterior of the extension tubes. Avoid using harsh chemicals or abrasive materials. For electronic contacts, use a clean, lint-free cloth and isopropyl alcohol if necessary, ensuring no residue is left.
• Storage: Store the extension tubes in a dry, dust-free environment when not in use. Keep them away from extreme temperatures and humidity.
• Handling: Always handle the tubes by their body, avoiding contact with the electronic pins or optical surfaces (though these tubes contain no glass elements).

9. Troubleshooting

Issue: Autofocus is slow or not working.

Solution:

• Check if the tubes are securely attached to both the camera body and the lens.
• Ensure the electronic contacts on both the tubes and your lens/camera are clean.
• When using multiple tubes, especially all three, autofocus performance can be significantly reduced. Consider switching to manual focus for better precision.
• Macro photography inherently has a very shallow depth of field. Ensure sufficient light is available for the camera's autofocus system to operate effectively.

Issue: Tube is difficult to attach or detach.

Solution:

• Ensure proper alignment of the mounting marks before rotating to lock.
• Press the release button fully when attempting to detach. Do not force the connection.
• Inspect the bayonet mounts for any debris or damage that might obstruct smooth attachment/detachment.

Issue: Images are dark or underexposed.

Solution:

• Extension tubes reduce the amount of light reaching the sensor. You may need to increase ISO, use a wider aperture (lower f-number), or add external lighting.
• Refer to the "Exposure Factor" in the magnification table (Section 7) for guidance on adjusting exposure.

10. Specifications

11. Warranty and Support

For warranty information or technical support regarding your Meike MK-N-AF1-A Macro Extension Tube Adapter, please refer to the official Meike website or contact your retailer. Keep your purchase receipt as proof of purchase for any warranty claims.

You can visit the Meike Store on Amazon for more product information and contact options.