The 1981 Minolta MD 50mm f/2 was introduced as an alternative to the standard f/1.7 kit for Minolta film cameras. It was built on the 3rd generation MD mount (MD-III) for full compatibility with Minolta’s latest features. This lens has become one of my favorites to use on the a7 and in this review I’ll cover how I came to that conclusion.
Build Quality and Handling
The lens itself is quite small with a recessed front element. This design is a smart choice as it protects the front element not only from flares but from dust and scratches as well. The build of the lens body is mostly high-quality plastic for a combination of durability and weight reduction – not the most solid lens out there but better built than most modern lenses today. Regardless of the plastic build, the focus ring is smooth and offers good resistance. The aperture ring is plastic as well and clicks solidly when turned.
Combined with the length of the adapter the lens balances nicely on the a7. It’s no bigger than most modern full frame lenses and in fact is much smaller in some cases.
A Word on Disassembly
Most Minolta MD primes aren’t difficult to disassemble and the MD-III 50/2 is no exception. You don’t even need a camera spanner to take it apart, but you might need a small tube with a sticky end to unscrew the front name ring. If it’s not on too tightly, you may be able to loosen it with your fingers. The only dedicated tool you’ll need is a small screw driver to remove the optical groups and rear mounting plate. Matt Bierner (link) on YouTube has a disassembly video for this specific lens.
I mention this because I fully cleaned and re-lubed my copy. It took me no longer than an evening with the only difficulty being re-calibrating for infinity focus. If you want to disassemble this lens know that it is one of the easier ones.
This lens is currently priced at around $30 – $50 on ebay. There’s no shortage of this lens’ availability so you may get one for even less.
- f/2 – Central sharpness and contrast start off good with the corners falling behind.
- f/2.8 – Sharpness and contrast in the center are now great, corners are improving.
- f/4 – Central sharpness doesn’t change much but corners continue to improve.
- f/5.6 – Corners are great now, the center is still excellent.
- f/8 – Excellent sharpness across the entire frame.
- f/11 – Diffraction beings to affect contrast to a small extent.
- f/16 – We’re well into diffraction territory here with a noticeable drop in sharpness and contrast.
Lateral aberrations are already low starting at f/2 and are gone by f/5.6. I had a hard time spotting them until I began inspecting at the pixel level.
Longitudinal aberrations aren’t a problem at all with this lens.
I see a very tiny amount of barrel distortion – negligible for most applications.
Heavy at f/2, reduced at f/2.8, affects extreme corners at f/4, negligible at f/5.6 and beyond. My wall wasn’t completely free from shadows which is why the bottom is darker.
Most older 50mm film lenses don’t perform too well here and the Minolta is no exception. Coma isn’t fully corrected until f/5.6.
Bokeh on this lens is nothing to rave about, but it’s also not bad. The only real issue I’ve come across with it is a heavy amount of mechanical vignetting (cats eye effect). In these cases, bokeh can appear a little busy and even swirly.
At closer distances bokeh can be quite smooth.
At f/2.8 and up, bokeh takes on a hexagon shape.
More often than not I don’t have a problem with the bokeh on this lens.
Flaring and Ghosting
Veiling flare is reasonably controlled for a lens of this age, but ghosting can be an issue.
I find that when there’s a bright source of light in the frame it will produce blue ghosts of varying size across the frame. Even a street lamp is enough to provoke them.
There’s also a small risk of incident flares popping up when the sun is outside the frame. It seems the recessed lens elements aren’t completely shielded from these. A small lens hood will help prevent them.
- High Sharpness
- Low aberrations
- Low distortion
- Good but not great contrast
- Veiling flare resistance
- Build quality
- Heavy vignetting at f/2
- Lots of ghosting
- No coma correction at faster apertures
While this lens isn’t perfect, I think it makes smart compromises in its design. The only area I find that holds this lens back from greatness is its ghosting performance. Most of Minolta’s lenses don’t do well in that regard and this lens isn’t any different. Regardless of this short fall, for $30 – $50 you can’t go wrong with this little gem. It has many great qualities that allow it to perform well on modern mirrorless cameras.
Something that I feel sets this lens apart from other vintage lenses is it’s micro-contrast at f/2. While not impressive by modern standards, I found that it’s wide-open performance in this area is better than most other vintage lenses that I’ve used. Most other 50’s have high spherical aberration at maximum aperture that robs the image of micro-contrast. This effects focus peaking on my A7 by producing more of the “peaking effect” at f/2. It makes the lens easier to focus in a pinch and has a positive contribution to it’s usability.
This 50/2 has been my most used vintage lens over the past year. I’m still on the lookout for something that can one-up it for a good price, but until I find that lens I’ll continue to shoot with this one.