Minolta MD ZOOM 35-70 mm f / 3.5: A Diamond in the crown of the Empire Minolta.

Revising my “collection“ of lenses, I noticed that there are no full-frame manual focus lens with variable focal length (called zoom-lens).  A good zoom-lens which has been repeatedly mentioned on the network is a Minolta MD ZOOM 35-70 mm f / 3.5. The lens seemed interesting to me - a very practical range of focal lengths on a full-frame (for x1.5 crop become 53 - 105mm - well, interesting too) with a constant maximum aperture at all focal lengths. Besides the fact that this lens is a prototype for the Leica Vario-Elmar-R 35-70 mm f / 3.5 (for which, by the way, asking HUGE money...), its owners were heavily exited for the image quality. For example: "A little diamond", "Best lens in this class", and even - "Image quality is not worse than the lenses with fixed focal length lenses".  The last statement is inspired me to do this test. Minolta MD ZOOM 35-70 mm f / 3.5 that I own is a second version (production of 1981-1983) without macro option, and with six blades in the aperture. Comparison of zoom lens with a prime lens is time-consuming and usually complicated, so I decided to make at a simple comparison in the near-field and far-field sharpens.  I think that bokeh and aberrations comparison of such different lenses are not legitimate. All prime lenses used for comparison are made by Minolta. At the short end of the lens it will be Minolta MD W.Rokkor 28 mm f / 3.5, in the middle - Minolta MD Rokkor 50 mm f / 1.4, and at the long end - Minolta MD Rokkor-X 85 mm f / 2. All of these lenses are related to the second generation of Minolta MD lenses released within 1979 – 1981 period. The mechanical and optical conditions of lenses are very good.

 

Group photo:

 

 

Parameters for comparison:

 

Sharpness of images in the center and the edge of the frame for a short distance (~ 1.0m)

 

Sharpness of images in the center and the edge of the frame for a long distance (~20m)

 

Since the Sony NEX- 6 camera was used during comparison, all the conclusions related to APS-C sensor with the size of 23.6mm x 15.7mm. A comparison series were started from the same equivalent aperture f3.5.

Sharpness of images in the center and the edge of the frame for a short distance (~ 1.0m)

Conditions: artificial lighting, ISO400, automatic white balance, Sony NEX- 6, a tripod, a two second delay before the shutter release.

 

A standard test format ISO- 12233 was used for the analysis. For the analysis, two models were used: in the center and on the edge of the frame.

 

Minolta MD ZOOM 35-70 mm f / 3.5 at 35mm Minolta MD W.Rokkor vs. 28 mm f / 3.5

 

 

And there is a first surprise. 28mm certainly is not 35mm but have to be sharp open wide of f3.5, which in fact does not. At the short distance Minolta MD ZOOM 35-70 mm f / 3.5 shows better performance than the Minolta MD W.Rokkor 28 mm f / 3.5!

Minolta MD ZOOM 35-70 mm f / 3.5 is decently sharp open wide, shows the maximum sharpness at f8.0-f11 and the sharpness on the edge of the frame is good as well.

 

Minolta MD ZOOM 35-70 mm f / 3.5 at 50mm vs. Minolta MD Rokkor 50 mm f / 1.4

At 50mm mid-range focal length for Minolta MD ZOOM 35-70 mm f / 3.5 is hard to compete with the present prime lens. It shows worse sharpness for whole apertures range. It should be noticed that the difference is not so big. Maximum sharpness detected at f8.0 - f11 apertures.

 

Minolta MD ZOOM 35-70 mm f / 3.5 at 70mm vs. Minolta MD Rokkor-X 85 mm f / 2

 

 

And within this range Minolta MD ZOOM 35-70 mm f / 3.5 shows worse sharpness at whole apertures range. Now the difference is quite visible. Although it cannot be said that the lens shows smear picture. Simply Minolta MD Rokkor-X 85 mm f / 2 is a very good lens. Maximum sharpness of Minolta MD ZOOM 35-70 mm f / 3.5 is in a range of f8.0 - f11 apertures.

 

Sharpness in the center and on the edge of the frame for a long distance (~ 20m).

 

Terms: natural light, ISO100, automatic white balance, Sony NEX- 6, a tripod, a two second delay before the shutter release.

The neighbor's house was used as a model. Two objects in the center and at the edge of the frame were used for the analysis of.

 

Since for the long distance photography a large depth of field is mainly used, two apertures (f5.6 and f11) were tested.

 
Minolta MD ZOOM 35-70 mm f / 3.5 at 35mm Minolta MD W.Rokkor vs. 28 mm f / 3.5

 

 

In the far-field Minolta MD ZOOM 35-70 mm f / 3.5 shows worse performance than Minolta MD W.Rokkor 28 mm f / 3.5. Again, we cannot say that the difference is huge, but Minolta MD W.Rokkor 28 mm f / 3.5 looks better. Apparently Minolta MD W.Rokkor 28 mm f / 3.5 has been designed  to show the best performance is in the far field. As a decent wide-angle lens.

 

Minolta MD ZOOM 35-70 mm f / 3.5 at 50mm vs. Minolta MD Rokkor 50 mm f / 1.4

 

 

It is difficult to tell which lens is sharper in the center of the frame.  Both are very good.  On the edge of the frame, however, Minolta MD Rokkor 50 mm f / 1.4 gives a sharper image.

 

Minolta MD ZOOM 35-70 mm f / 3.5 at 70mm vs. Minolta MD Rokkor-X 85 mm f / 2

 

 

Magnificent sharpness of both lenses tested on both apertures. At least in the center of the frame ...

 

Conclusions:

 

First, the zoom lens cannot compete with a lens with a fixed focal length. No doubt. Not to mention the difference in the maximum aperture. Second, we must admit - all praises on this lens completely justified. Mid-range zoom with a constant maximum aperture f3.5 shows very good sharpness at whole zoom range. When the aperture stops down to values of f5.6 - f8.0 the lens become very sharp. The excellent performance in the far field particularly should be highlighted. And… try to take a video with this lens. The video performance is very attractive. It remains focussed while zooming, which is very important.  The last, I cannot wait to try it on a full-frame SONY A7/A7r - when the price of this camera will become affordable.

 

As a bonus - an example of bokeh Minolta MD ZOOM 35-70 mm f / 3.5 at 70mm and f3.5.

 

Samples:

Minolta MD W.Rokkor 28 mm f / 3.5

Minolta MD Rokkor 50 mm f / 1.4

Minolta MD Rokkor-X 85 mm f / 2

Minolta MD ZOOM 35-70 mm f / 3.5