November 2007 Archives
The following lenses represent an unusual value. They are not necessarily the cheapest or the best quality available, but they all represent a very high quality for a reasonable price.
I've written this guide from the perspective of a longtime and Minolta user. I own the lenses below, but I don't buy or sell them. You'll have to find them on eBay or elsewhere on the web, and all the usual caveats about careful online shopping, checking seller reputation, and avoiding fraudulent listings applies. I wish simply to point you to lenses for the Sony Alpha / Minolta Maxxum mount that offer excellent value.
50mm f/1.4
This standby standard lens comes in several variants. They are all the same optical design and are all essentially equal. Some have different filter thread sizes (some are 49 mm, other 55 mm) and the newer ones have focal distance information to aid newer flash systems (these have a D at the end of their label). A really rare variant is the 1988 version with the crossed x’s (XX), a logo design that was quickly changed after complaints from Exxon, and thus extremely rare and valued by collectors. And Sony has released their version under the Alpha brand. From the point of view of basic performance they are all the same.
The 50mm f/1.4 is an extraordinarily sharp lens with one of the highest MTF ratings of any lens available. You really have no idea what your camera is capable of until you try this lens with it. If all you've had is the kit lens you'll be astonished by how much better your photos can be. Things just sparkle with contrast and clarity. The downside is no zoom, but the upside is worth it if you value really, really good pictures.
This lens costs around $325 new, and can sometimes be had in the used range for under $200. That isn't cheap, unless you consider just how amazingly good photos with this lens are in comparison to what you are currently using. Then it looks like a bargain.
35mm F/2 (rare)
Discontinued in the early 90s, this lens is the less expensive version of Minolta's legendary 35mm f/1.4, a $1400 lens. It's extraordinarily sharp at all apertures and all focal distances, and belongs to the small club of lenses with an MTF rating of over 4 (from a possible five). Better yet, it shines on 1.5x crop factor digital SLR’s like the Maxxum 7D, 5D and the Sony Alpha-100 and -700, where it is effectively a 50 mm f/2. It's hard to give a current price since they so seldom come up for sale, but a range of $200 to $400 for a good condition copy seems reasonable.
100mm f/2 (rare)
Another classic lens from the early 90s, long since discontinued. This lens is among the sharpest available for any system, with an MTF of 4.6. It doesn't do well on macro, and only focus is down to about 3 feet, but for any other purpose is just stunning. The bokeh (out of focus area blur smoothness) is among the best available, and it takes stunningly sharp portraits that yet isolate the subject against a background in a way that no general purpose is zoom is capable of (and that's just a function of lens design; a lens can't be all things, and zooms by design tend to have a very deep field of focus, which is really great for amateurs that makes it hard to get a professional looking portrait). This one too is quite difficult to find, and thus difficult to price, but even at $400 would be a good buy.
70-210 f/4 “the beer can”
This lens is truly become a cult classic. It used to be you could get them routinely for under $100, but those days are long gone and today they are pushing above $200. It's strange that it 30-year-old lens design remains this popular. But it's popular for a reason. The only downside is it's size; it does everything else amazingly well. It focuses close to about 12 inches. It is razor-sharp edge to edge at any focal length to infinity. It’s at f/4 at 210mm (on a dSLR that's an effective 315mm). And the pictures just look amazing. What more is there to say? You can get a better lens for $1500, but there's not much else below that that comes anywhere close to this one.
100-200 f/4
This lens has not yet achieved cult classic status, and as such still routinely sells for under $100. The contrast to this and the "beer can" above is a perfect lesson in how lens design is a trade-off of factors. This lens is very small and lightweight. It's also amazingly sharp. So what did they have to give up? Close focusing. Minimal focusing distances over 3 feet, so don't expect to use it for macro shots. But such a tiny lens doesn't scream "pro photographer", so it's useful where you don't want to stand out. Yet it certainly takes photos every bit as good as lenses costing 10 times as much. And while there are plenty of medium-telephoto zooms that you can choose from, none this small come anywhere close to having this level of image quality, and none with this image quality are anywhere close to this price. This is probably the best value lens around.
35-70 f/4
The little brother to the "beer can", this lens was designed at the same time and sold to complement its much larger sibling. In the days of dSLR cameras, the focal length is somewhat limited, becoming an effective 50-105mm zoom. But someday in a few years Sony will start selling full frame dSLR’s with the alpha mount and this little lens will become popular again. It has all the quality of the "beer can", including an amazing edge to edge sharpness and a constant f/4 aperture, and its focal range is actually the most commonly used for film cameras. Finally, add the fact that they routinely sell for under $50, and you have a real value bargain. Just don't confuse it with other 35-70mm lenses that aren't nearly as good, such as the f/3.5-4.5 variants. This one was also discontinued in the early 1990s.
24-105 f/4-5.6 D
Back when Minolta released what is probably the best film camera of all time, the Maxxum 7, they also developed a brand-new general purpose zoom lens to be the high-end kit lens for the system. Most kit lenses sell separately for under $100, but this one has a list price of $500, so it's clearly no ordinary kit lens. In general use it’s an all around excellent lens, long enough that you don't often reach for a telephoto, yet broad enough to work even on a dSLR with 1.5x crop factor, having a functional 35mm bottom end. Sony reissue this one with an alpha label on it, so you can have it new for $440 or you can pick up a used Minolta version for under $200 if you can find one. I've probably shot close to 40,000 images with this on the Maxxum 7D and many have been published. If you leave the house with just one lens, this is the one you’ll want (unless your budget stretches to the thousands). It represents an excellent value when you compare overall image quality to the price you pay.
There are plenty of other excellent lenses for the Maxxum/Sony Alpha lens mount, and most of them are much more expensive. But these all represent extraordinary value because they produce exceptional image quality at reasonable prices.
I originally got the Sigma 10-20mm f/4-5.6 EX DC HSM for my Maxxum 7D because I needed a good wide-angle lens for landscape and indoor photography. Because the Maxxum 7D has a sensor that is smaller than 35mm film, this acts as a built in zoom factor of 150%. What this means is all 35mm lenses are essentially zoomed 1.5 times closer than they are when used on a 35mm film camera body. This is great for telephoto lenses, because you get even more zoomed out of them. Your standard 210mm lens functions as a 315mm lens, and at the same aperture. On the wide-angle of things this is problematic. A 24 mm lens, normally an excellent wide-angle, is functionally a 36mm lens. Even an unusually wide 14 mm lens becomes a 21 mm. So the Sigma 10-20mm zoom functions effectively as a 15-30 mm zoom lens. Yet that is wide enough.
More than most lens manufacturers, Sigma suffers from uneven quality control (maybe less so now than 20 years ago but still to some degree). What this means is that individual samples of Sigma lenses can vary widely in their quality. A good one is very, very good. A bad one can be quite poor. And they can be brand-new in the box sitting next to each other on the shelf. The only way to really know is to test them. There have been numerous reports of individual examples of the Sigma 10-20mm which focus sharply only on one half of the lens, the other half being always slightly blurry (these are reported more by owners of the Nikon and Canon mount versions, but then most of these lenses are probably sold in Canon and Nikon mounts, so by virtue of their being more of them they'll also be more reports of defective ones).
I was fortunate in that the lens I purchased did not have any problems. Wide-open there is a lot of softness at the edges, but stopped down a bit its sharp all the way across. There are minor issues of vignetting towards the edges on high contrast subjects, but you only notice this zoomed to 100% in Photoshop. In all this is a great lens for the price, and really allows for wide-angle photography with DSLR cameras.
Here are a few images. Camera us the Maxxum 7D firmware 1.10. Click on them for a full size 2000x3000 4mb jpeg version.
Optimal sharpness:10mm @ f/8, 1/300th (Grand Teton National Park)
Optimal sharpness:20mm @ f/9, 1/250th (Zion National Park)
Optimal sharpness:10mm @ f/8, 1/640th (Homolavi Ruins State Park, AZ)
Wide open: 10mm @ f/4, 1/30th [no tripod; love that anti-shake!] (Zion National Park)
