Info
Meike Extension Tube Set - Sony A
The metal Meike Delta Extension Tube Set consists of three extension tubes that can be used separately or combined. An extension tube is placed between the lens and your camera. This allows you to get closer to the subject and make the subject appear larger in the picture.
Maintains quality and features
A spacer ring is hollow: it does not contain a lens system and therefore does not change the quality of your pictures! All automatic functions are maintained. When using the automatic metering system, no compensation of your exposure will be needed. Also the auto focus of your lens will still work.
How does a spacer ring work?
A spacer ring creates a larger distance between the image sensor of the camera and the rear lens of the camera objective. 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 13mm spacer ring, the magnification factor of the lens becomes as follows.
Maximum magnification with 13mm ring = 0.13 + (13 / 85) = 0.13 + 0.15 = 0.28
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 + 0.22 = 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 69mm intermediate ring = 0.13 + (69 / 85) = 0.13 + 0.81 = 0.94
Please note
Please note that when using all three stacked spacer rings there is a loss of light of approximately 2 stops!
Characteristics
In the box
- 1 x 13mm extension tube
- 1 x 20mm extension tube
- 1 x 31mm extension tube