Lens: Olympus 38mm f/3.5 bellows lens
Vintage: 1970's.
Lens Mount: RMS
Needed Adapters: I use an RMS to T2 adapter and then a T2 to camera specific adapter. Easy to find on eBay.
Preferred Mounting: Normal, not reversed
Filter Thread: None
Street Price: $300-$700 in good used condition. Prices vary a lot online, shop around.
Controls: Aperture preset and aperture setting.
Aperture: 8 blades.
Basic Function: Requires a bellows to set focus and magnification.
| Extension | Magnification | Working Distance |
| adapters | 1.13 | 60 mm |
| 25 mm | 1.82 | 48 mm |
| 5 cm | 2.30 | 42 mm |
| 9 cm | 3.33 | 37 mm |
| 13 cm | 4.39 | 34 mm |
| 19 cm | 5.97 | 32 mm |
| Est. Focal Length: 38.2 mm | ||
Appearance:
Resolution vs. Aperture:
This lens is at its sharpest at f/5.6, a little smaller than I would like. Newer lens like the Olympus 38/2.8 improve on this and perform best at around f/4.
The most detailed aperture is f/5.6 also.
Corner Sharpness vs. Aperture:
The field is virtually flat across the aperture range at m = 2.3, the lowest setting for my bellows.
Sharpness and Resolution vs. Magnification:
This lens produces sharp and detailed images across its magnification range of just above 1:1 to about 6:1.
The corner sharpness is OK at the lowest magnification and extremely good above that. This lens works well when directly mounted on the camera, but it is really made to work with at least a little extension.
Performance: Sharpness vs. Magnification:
I have 4 lines that represent levels of performance from outstanding (top) to fair (bottom). This shows where this lens fits into the hierarchy that I have created.
The Olympus 38mm shows sharpness performance that varies from good at the low-end to fair at the high-end of its magnification range.
Performance: Resolution vs. Magnification:
I have 4 lines that represent levels of performance from outstanding (top) to fair (bottom). This shows where this lens fits into the hierarchy that I have created.
The Olympus 38mm shows resolution performance that varies from very good at the low-end to fair/poor at the high-end of its magnification range.
Resolving Power vs. Magnification:
This graph represents the smallest details that are able to be resolved by this lens at various magnificaitons. If the number doesn't get smaller as the magnification rises, there is little benefit to going up in magnificaiton with this lens. This situation is also called empty magnification.
Good resolution, with improvements tailing off above 4:1.
Chromatic Aberration:
This lens show minimal to moderate color fringing in the center (about 0.23 - 1.27 pixels) and mild to moderate on the periphery (0.074 - 0.098%).
There is mild axial CA on out-of focus details (see image below) as shown by a slight red fringe on the right and a slight green/cyan fringe on the left of the image.
Longitudinal CA:
Image Contrast: Image contrast is good, although not as high as a modern macro lens.
Flare: This lens shows no significant flare during testing.
Distortion: This lens shows no significant distortion during testing.
Image Samples:
About 1.8:1 magnification, f/5.6, focus stack of 34 images, resized:
Pixel level crop from the image above:
There is very good pixel level detail, no problems.
About 6:1 magnification, f/5.6, stack of 18 images, resized:
Pixel level crop from the image above:
There is good pixel level detail, no problems.
Conclusion:
This is a lens that performs well, but is outperformed by newer lenses. This performance drop is mainly related to the smallish best aperture of f/5.6. Newer lenses in this focal length range tend to work best around f/4, improving sharpness and resolution. It tends to be a little expensive for the performance, but comparable to a typical bellows lens. The field is extremely flat at all apertures unless you use the lens directly on the camera without extension, and even then it is OK. The chromatic aberration is mild to moderate, more than the newer models tend to show. The contrast is good, but not quite that of a modern macro lens.
Overall this lens performs well, but its age shows. For a similar price, you can get better performance in a newer bellows lens (Olympus 38/2.8, Canon 35/2.8). For considerably less you can get a Schneider 40mm enlarging lens that will outperform it in sharpness and resolution although the corner performance won't be quite as good. The only advantage it has over the newer 38/2.8 is that it has an RMS mount which is easier to adapt to any camera. The 38/2.8 has an OM mount that is harder to adapt to other brands of cameras.