When I purchased my first DSLR (Konica Minolta D5D) the telezoom Konica Minolta 75-300D f4.5-5.6 was provided in the kit. I used this zoom for my favorite sports shooting (windsurf, kitesurf, sailing race) and was pleased with the fast enough auto-focus. But I never loved the washed out colors and the poor sharpness of this zoom even at f/8. With the Sony Alpha 700 and it's 12Mpix sensor it was worse for the sharpness.
As a M42 addict and loving my Jupiter 9 and Jupiter 37A, I purchased a Jupiter 21M (200mm f/4.0) expecting it would be as good as it's little brother, the 135mm Jupiter 37A.
At the same time I win an auction for a Minolta Beercan. The legendary Beercan! There is a real hype on this zoom. This 70-210mm zoom has a constant f/4.0 aperture and was born in the middle of the eighties when Minolta introduced the first autofocus lenses. This zoom is a legend for it's image quality and build quality. It is very versatile because of it's constant aperture and with a minimum focus distance of 1100mm (even @210mm).
I also purchased at the same time on the aftermarket it's big brother also called the Big Beercan i.e. the first Minolta AF 75-300 f4.5-5.6 (this is a big familly!). It does not feature the same constant aperture as the Beercan the has a wider range. The mnimum focus distance is 1500mm (nice @300mm). This zoom is difficult to find but is less hyped than the Beercan.
I have opinion on all of these lenses when everyday shooting, but I would like to share with you this static comparison.
The lenses are compared with my Sony Alpha 700 DSLR @100iso, Super Steady Shot off, on a tripod. The files are in cRAW format.
The scene is:
@200 Center crop (100%)
| f/ | M42 Jupiter 21M |
Minolta 70-210 Beercan |
Minolta 75-300 Big Beercan |
Konica Minolta 75-300 D |
| 4.0 |  |
 |
||
| 5.6 |  |
 |
 |
 |
| 8.0 |  |
 |
 |
 |
@200 corner crop (100%]
| f/ | M42 Jupiter 21M | Minolta 70-210 Beercan |
Minolta 75-300 Big Beercan |
Konica Minolta 75-300 D |
| 4.0 |  |
 |
||
| 5.6 |  |
 |
 |
 |
| 8.0 |  |
 |
 |
 |
Conclusion
| f/ | M42 Jupiter 21M |
Minolta 70-210 Beercan |
Minolta 75-300 Big Beercan |
Konica Minolta 75-300 D |
| 4.0 center | 1 | 2 | ||
| 4.0 corner | 1 | 2 | ||
| 5.6 center | 1 | 4 | 2 | 2 |
| 5.6 corner | 1 | 4 | 3 | 2 |
| 8.0 center | 1 | 4 | 1 | 3 |
| 8.0 corner | 2 | 4 | 2 | 1 |
I was expecting a lot from the Jupiter 21M because I was fully satisfied with the little brother Jupiter 37A (135mm M42 prime).
What a great lens : the Jupiter 21M is the sharper at all aperture. It correspond to what I observed in real life shooting. I think it would be interesting to compare it with a fast 70-200 f/2.8 (expensive!) zoom @200 @f/4.0
The beercan is 4X more expensive than the M42 prime Jupiter 21M. Both are as fast with a f/4.0 maximum aperture. I was also expecting a lot from the beercan. I have 2 copies of the beercan an compared the best one. The result does not correspond to the hype on this zoom. The beercan is the worst lens of this match@200mm! It partially correspond to what I observed in real life shooting because I have been disapointed by the beercan many times.
An other surprise is the comparison between the Minolta 75-300 big beercan and with the D kit telezoom. They offer roundly the same results which are better than with the beercan. So at 200mm, tke kit tele-zoom is not a bad lens at all and is sharper than my 2 beercans. The Big beercan is also sharper than the beercan but I am not surprised with this point because in reel live shooting I enjoy the big beercan. I will have difficulties do decide wich 75-300 to keep!
Keep in mind for zoom lenses compared in this match is at@200mm. Do not forget to look to my other comparisons.
Keep also in mind that the purpose of this match is just to compare the sharpness, and looking a 100% crop make only sense for huge (e.g. 75cm * 50cm) prints.
