Diopters are optical close up lenses that make macro photography easy.
•When added to a lens they greatly narrow the depth of field while reducing the minimum focusing distance of your lens.
•The effective focal length of the dioptere are:
• +1 = 1000mm
• +2 = 500mm
• +3 = 333mm
• +4 = 250mm
• +5 = 200mm
Reviewed by 2 customers
I recently used this filter on my Pentax K-7 and Pentax 17-70mm lens to photograph close-ups of cut stones including Agate and Tiger Eye. I got to within 3 inches of the subject and got excellent detail and color.
The Voigtlander Nokton is a first-rate lens, but the magnification is only 1:6 at the close-focusing distance so it is not well-suited for macro photography. Bought the B+W +3 to see if a low diopter close-up lens could increase magnification without compromising IQ, and selected an oversized model with a step-up ring to see if this could eliminate edge degradation (67mm CUL thread to 58mm lens filter thread). Even at a glance test results were remarkable: images were extremely sharp nearly edge-to-edge at f/11 and f/13. No distortion or vignetting, and hardly any color fringing, was seen. Contrast was excellent. The only problem was that the lens hood would not fit over the ring, leaving the outer element vulnerable to glare and to getting scratched. The 58mm VoigtlÃ¤nder is tiny and the B+W close-up lens is no bigger than a filter, so the set gets my vote for "most portable, inexpensive, pro-quality macro/portrait/landscape combo ever." 10 out of 10!