Nikon F and F2 Close-Up Lenses
All of these close-up lenses work by effectively reducing the focal length of the lens behind them. Close-up lenses are an inexpensive and fairly high-quality way (for the two-element achromats) to obtain decent magnifications without buying a macro lens. In general, stacking close-up lenses is not recommended, but if you find that you need to, put the higher-powered lens closer to the lens.
Some more math for you:
[EFL] = 1000/{(1000/[MFL]) + [DP]}
where
[EFL] is the effective focal length, in millimeters
[MFL] is the marked focal length (i.e. the focal length of the bare lens), in millimeters
[DP] is the diopter power, as given by the close-up lensBy calculating the effective focal length, you can go ahead and figure out what the aperture is ... or you can use stop-down metering, which is probably more efficient. Similarly, you can calculate the new focussing distance (in centimeters) of the lens + closeup combination with the formula
[focussing distance] = 100/[DP]
Note that the focussing distance is virtually independent of the actual focal length of the lens in use.
Attachment Lens Number 0
Attachment Lens Number 1
Attachment Lens Number 2
Attachment Lens Number 3T
Attachment Lens Number 4T
Attachment Lens Number 5T
Attachment Lens Number 6T
This lens is intended for use with telephotos (hence the "T" at the end of the name) but is reputedly excellent with all lenses that it'll fit.
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