Olympus OM system close-up and macro equipment

Zuiko Macro Lens 38mm f/3.5

Introduction

This is one of the original set of 3 bellows macro lenses for the Olympus OM system and was first produced in 1972. Unlike nearly all of the other OM lenses, this one has a preset manual diaphragm instead of an automatic one, and so exposure has to be measured withe lens stopped down. Focusing is easier with the aperture wide open. Like the other 2 manual macro lenses, the aperture scale appears upside down when viewed from behind the camera. This is because this lens was expected to be used pointing downwards on a copy stand or a macro stand, so that the scale appears right way up when viewed from the front.

This macro lens is designed for magnifications from 1.8× to 6× and so it is appropriate for objects ranging from 20×13 mm down to 6×4 mm.

The Zuiko Macro 38mm f/3.5 lens is intended for use with the Auto Bellows, although it can also be used with the Telescopic Auto Tube 65–116 that was introduced in 1980. It can also be used with extension tubes, but with fixed magnifications.

The Zuiko Macro 38mm has a small screw thread mount (RMS – Royal Microscopical Society – thread, 0.8″ diameter, 36 t.p.i.), the same as many microscope objectives, and requires an Objective Lens Mount PM-MTob to convert it to the OM bayonet fitting.

This lens pre-dates the macro flash and ring flash units, and so does not have a filter mount for attaching them. However, it is possible to use strong glue to fix an empty 49mm filter mount to the front of the PM-MTob adapter.

In 197?, this lens was discontinued and replaced by the Zuiko Auto-Macro 38mm f/2.8 lens, which is faster, has an automatic diaphragm, has a standard OM bayonet instead of the RMS screw thread, has helicoid fine focusing, and has a 49mm filter mount for attaching the macro flash units.

Versions

This was one of the very first OM lenses, and some boxes were made with the original “M SYSTEM designation that was replaced in January 1973 by the familiar “OM SYSTEM” designation. It is not known if any “M SYSTEM” lenses were made.

  1.  ZUIKO MACRO 1:3.5 f=38mm  (200xxx, single coated)
  2.  ZUIKO MC MACRO 1:3.5 f=38mm  (202xxx, 203xxx, 300xxx multicoated)
  3.  ZUIKO MACRO 38mm 1:3.5  (301xxx, multicoated)

Features

Optimum range ×1.8 – ×6.0
Working distance 32–46 mm
Lens elements 5
Lens groups 4
Lens coating Early versions single coated
Late versions multicoated
Iris diaphragm Manual (pre-set)
Iris blades 8
Maximum aperture f/3.5
Minimum aperture f/16
Pupil ratio (exit/entry) 1.03
Focusing helicoid None
Length 28 mm, 1.1 in
Maximum diameter 43 mm, 1.7 in
Weight 90 g, 3.2 oz
Mount RMS screw thread (0.8″ diameter, 36 t.p.i.)
Adapter (required) Objective Lens Mount PM-MTob
Focusing screens 1-4, 1-4N, 1-10, 1-11, 1-12, 2-4
Front cap None
Rear cap None (lens screws into case)
Case Hard plastic
(same as 20 mm f/3.5 macro)
Hood None
Filter size 32 mm (slide-on)
US catalog no. 103-710
Introduced 1972
Discontinued 1985
Zuiko Macro Lens 38mm f/3.5
Zuiko Macro Lens 38mm f/3.5 on PM-MTob adapter


Cross-section
Cross-section


Plastic case
Plastic case

Magnification range with Auto Bellows

Lowest magnification ×1.8 Subject area 19.8×13.2 mm Working distance 46 mm
Highest magnification ×6.1 Subject area 5.9×3.9 mm Working distance 32 mm

Magnification range with Telescopic Auto Tube 65–116

Lowest magnification ×? Subject area ?×? mm Working distance ? mm
Highest magnification ×? Subject area ?×? mm Working distance ? mm

Accessories

The Objective Lens Mount PM-MTob is required in order to mount the lens on the Auto Bellows. A Lieberkühn Reflector and a Mirror Housing were made to fit this lens.

See also:    Close-up and Macro Photography – Bellows Macro Lenses

Going digital

This lens has no interaction with the camera body. The manual pre-set mechanism for closing the iris diaphragm works exactly the same on film and digital cameras.

The following tables are based on those in the instruction leaflet, with adjustments for different sensor sizes and for any additional extension needed to allow the release lever on the rear of the Auto Bellows to clear an overhanging pentaprism or flash.

Magnification table for Auto Bellows with Canon EOS 5D MkII

36×24 mm sensor, with 7 mm extension tube between bellows and OM/EOS adapter

Magnification 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
Subject area (mm) 18.0 × 12.0 14.4 × 9.6 12.0 × 8.0 10.3 × 6.9 9.0 × 6.0 8.0 × 5.3 7.2 × 4.8 6.5 × 4.4 6.0 × 4.0
Bellows scale* (mm) 68 87 106 125 144 163 182 201 220
Lens to subject distance (mm) 44 41 38 36 35 34 33 32 32

Magnification table for Auto Bellows with Canon EOS 40D

22.2×14.8 mm APS-C sensor, with 14 mm extension tube between bellows and OM/EOS adapter

Magnification 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
Subject area (mm) 8.9 × 5.9 7.4 × 4.9 6.3 × 4.2 5.55 × 3.7 4.9 × 3.3 4.4 × 3.0 4.0 × 2.7 3.7 × 2.5
Bellows scale* (mm) 80 99 118 137 156 175 194 213
Lens to subject distance (mm) 41 38 36 35 34 33 32 32

Magnification table for Auto Bellows with Olympus E-1, E-300, E-330 and Micro Four Thirds

17.3×13.0 mm Four-Thirds sensor, with no extension tube between bellows and OM/Four Thirds adapter

Magnification 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
Subject area (mm) 8.65 × 6.5 6.9 × 5.2 5.8 × 4.3 4.9 × 3.7 4.3 × 3.25 3.8 × 2.9 3.5 × 2.6 3.1 × 2.4 2.9 × 2.2
Bellows scale* (mm) 75 94 113 132 151 170 189 208 227
Lens to subject distance (mm) 44 41 38 36 35 34 33 32 32

Magnification table for Auto Bellows with Olympus E-3, E-410, E-500, E-510, E-620

17.3×13.0 mm Four-Thirds sensor, with 7 mm extension tube between bellows and OM/Four Thirds adapter

Magnification 2.0 2.5 3.0 3.5 4.0 4.5 5.0 5.5 6.0
Subject area (mm) 8.65 × 6.5 6.9 × 5.2 5.8 × 4.3 4.9 × 3.7 4.3 × 3.25 3.8 × 2.9 3.5 × 2.6 3.1 × 2.4 2.9 × 2.2
Bellows scale* (mm) 68 87 106 125 144 163 182 201 220
Lens to subject distance (mm) 44 41 38 36 35 34 33 32 32

* The bellows scale should be read at the rear of the body mount, with the lens mount positioned at the front end of the rail.

Instruction leaflet

Reproduced with permission from the copyright owner, Olympus Optical Co., Ltd
Printed 0378

ZUIKO MC MACRO 1:3.5 f=38mm

This lens was designed exclusively for macrophotography in conjunction with the Auto Bellows (an optional coupling attachment * is necessary). The lens is multicoated to minimize flare and ghost images. The assignment for this lens is to exert high resolution and contrast at magnifications from 1.8× (13mm × 20mm) to 6× (4mm × 6mm). In macrophotography at such high magnifications, illumination, camera stability and subject’s position become hard to fine adjust. The use of a macrophoto stand and accessorial illumination devices is recommended. The PMT-35, a highly sophisticated macrophoto apparatus, is available for advanced amateurs and skilled experts. Compatible focusing screens are 1-11 and 1-12.

The 1-12 (cross hairs-clear field type) offers a brighter image, but the meter built into the OM-1 and OM-2 (on MANUAL) does not give correct light readings. With the OM-2 on AUTO, correct exposures are made on the film but the meter needle does not give correct light readings.

* Objective Lens Mount PM-MTob

Specifications
Focal length: 38mm • Angle of view: 90° (at high magnification) • Optical construction: 5 elements in 4 groups (multi-coated) • Diaphragm: Manual • F stop range: 3.5–16 • Minimum photographic range: 13mm × 20mm – 4mm × 6mm • Focusing: With Auto Bellows • Weight: 90g (3.2 oz) • Length: 28mm (1.1″) • Maximum diam: 43mm (1.7″)

CLOSE-UP & MACROPHOTOGRAPHY TABLE (With Auto Bellows)

Subject Area Covered mm   18 × 12 16.4 × 10.9 15 × 10 13.8 × 9.2 12.9 × 8.6 12 × 8 10.3 × 6.9 9 × 6 8 × 5.3 7.2 × 4.8 6.5 × 4.4 6 × 4  
Magnification   2.0 2.2 2.4 2.6 2.8 3.0 3.5 4.0 4.5 5.0 5.5 6.0  
Scale (mm) 68 75 83 90 98 106 113 132 151 170 189 208 227 231
Lens vertex-to-subject distance (cm) 4.6 4.4 4.3 4.1 4.0 3.9 3.8 3.6 3.5 3.4 3.3 3.2 3.2 3.2

CLOSE-UP & MACROPHOTOGRAPHY TABLE (With Auto Bellows)

Subject Area Covered (in)     41/64 × 27/64   35/64 × 23/64   15/32 × 5/16   23/64 × 15/64   9/32 × 3/16   15/64 × 5/32  
Magnification   2.0 2.2 2.4 2.6 2.8 3.0 3.5 4.0 4.5 5.0 5.5 6.0  
Scale (mm) 68 75 83 90 98 106 113 132 151 170 189 208 227 231
Distance from lens to subject (in) 1 13/16 1 47/64 1 11/16 1 39/64 1 37/64 1 17/32 1 ½ 1 27/64 1 3/8 1 11/32 1 19/64 1 17/64 1 17/64 1 17/64

OLYMPUS
OLYMPUS OPTICAL CO. LTD.
43-2 Hatagaya 2-chome, Shibuya-ku, Tokyo, Japan

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Created 18th May 2001   —   Updated 8th August 2011
Copyright © 2001–2011 Alan Wood

Olympus OM system close-up and macro equipment