Meike Extension Tube Set Eco - Canon

Meike Delta Extension Tube Set - Canon Economy

The Meike Extension Tube Set consists of three extension tubes with a Canon EF plastic mount that allow you to significantly enhance the macro capabilities of your current lenses without sacrificing quality. When using the TTL metering system, no exposure compensation is needed. Also the auto-focus will keep working when using the new AF drive.

Ideal for macro photography

This three-piece set makes the small world big. You place a spacer ring between your lens and the camera. This allows you to get closer to the subject and makes the subject appear larger in the picture. A spacer ring has no lens system and is therefore hollow. All automatic functions of your camera are maintained. The three separate parts can be used independently or together. The more rings you use, the closer you can get to the subject.

How does an intermediary ring work?

A spacer ring increases the distance between the image sensor of the camera and the rear lens of the lens. This shortens the focusing distance of the lens, making it possible to focus closer on the subject. As a result, the subject is projected onto the sensor larger than it would be without a spacer ring. A spacer ring thus increases the magnification factor of a lens. This can be calculated using the following formula.

Maximum magnification with a spacer ring = lens magnification factor + (mm spacer ring / focal length) 

Suppose you have an 85mm lens with a magnification factor of 0.13. With the 12mm ring the magnification of the lens becomes as follows.

Maximum magnification with 12mm ring = 0.13 + (12 / 85) = 0.13 + 0.14 = 0.27

With the 20mm ring, the magnification of the lens becomes as follows.

Maximum magnification with 20mm ring = 0.13 + (20 / 85) = 0.13 + 0.24 = 0.37

With the 36mm ring, the magnification of the lens becomes as follows.

Maximum magnification with 36mm intermediate ring = 0.13 + (36 / 85) = 0.13 + 0.42 = 0.55

You can also combine the spacer rings, with all three spacer rings the magnification factor of the lens becomes as follows.

Maximum magnification with 68mm spacer ring = 0.13 + (68 / 85) = 0.13 + 0.80 = 0.93

Please note

Please note that when using all 3 stacked spacer rings there is a loss of light of approximately 2 stops!