Aspherical Boundaries

Since I made this post over a year ago, I’ve acquired a small army of Nikon manual focus lenses. I’ve bought them second hand by looking through a combination of local classifieds and eBay.

Nikon made the 28mm f/2.8 in three different optical designs:

• The 7 element model, introduced just before AI spec;
• The 8 element model, introduced with the AI-S spec, adding CRC to the older design. Still being made today;
• The 5 element model, as part of the Serie E line. Later reincarnated as the pre-D AF model.

My beaten up sample of the 7 element model is in its most common AI spec. The coating has taken quite a beating, especially to the rear element’s coating. As one would expect, however, this did not significantly impact the usability of the lens in every day use:

While this design is overshadowed by the later design’s reputation, it’s still certainly pretty good, especially stepped down a stop or two.

Sigma just announced a pair of new Fisheye lenses for cropped sensor cameras. The 10mm f/2.8 is simply a diagnal fisheye, giving 180 degrees of view along the diagnal of the picture. Nikon’s AF DX 10.5mm f/2.8G has served that function for a while now. Good to see a third party version though, especially with a ring USM motor.

More interestingly is the 4.5mm f/2.8. This is a circular fisheye. It projects a hemisphere of view onto a circle contained in the image (rest of it will be black). The first photo on this page shows you what a circular fisheye gives you. This is the first lens of its kind for crop sensors.

Nikon used to make these in various forms, most practical being the Nikkor 8mm f/2.8. This has been discontinued. Sigma makes a 8mm f/3.5 that is a lot smaller and cheaper, but also slower and not as good optically (or so I’ve heard).

Even more extreme is the basket ball sized 6mm f/2.8, which allowed you to see 220 degrees of view.

I wondered across this article today. It talks about the use of a wide angled lens for landscape photos.

It’s been said that the wide-angle lens is the hardest lens to use. At first, the temptation to go wide to include as much as possible in quite overwhelming. I’ve found that was my primary reason to go for a wider lens. As a result, I ended up with many shots that look like this:

Due to the presence of a lamp pole behind me, I was not able to go further back without including it in the frame. Therefore I went wide to include the whole tree in the frame. Notice however that this made the tree look small (especially the top part of the tree).

A lot of really effective wide angle shots are taken up close to the main subject. The idea goes that if you go wider and closer, the main subject stays the same size while the background dwindles. This kind of photo uses the wider angle to induce stronger sense of depth. I’m trying to get my head around this approach. I like the following shot a lot more. It’s a very different subject, but I think it illustrates the point.

Though I’m not making any claims about the artistic merit of this photo, I do think it is a more effective use of the same focal length.

Anyhow, have a look at this series of rants by Rockwell for similar advice on effective uses of the wide angle.

Photography is an expensive hobby to start. Before you’ve build up a sufficiently complete kit, there’s always this vague need to acquire more “stuff”. I’ve gotten as far as having focal range from 10mm to 210mm covered with several lenses. I’ve also got a flash, some filters and a tripod. A subset of this kit is my lightweight, manual focus film gear, centered around a 1985 vintage Nikon FG.

Anyways, I’ve got a 50mm lens on the camera. I could use the zooms too, but the weight generally gets a bit much for casual work. In fact, I’d like the film kit to be a lot more portable than my regular digital kit. This means no more than 2 or 3 small prime lenses. The usual lens question comes up: which ones? There is only one way to find out without buying and trying everything, and that is to use what you’ve got and see how is it being limiting.

I went up Table mountain on a day hike the last weekend, and did some shooting. I found that I’d like to go a bit wider than the 50mm. Much wider in most cases. Something in the 20-28mm range would be ideal. Alternatively, it would be nice to have something significantly longer than the standard lens for isolating parts of scenery, such as details of plants or a particular rock formation.

This reminded me of Thom’s lens recommendations: He suggests a 20mm f/4 and 100mm f/2.8 for a light kit. There is also some importance attached to having a common 52mm filter size.

Some research shows that the 20mm f/4 is pretty rare on the market. However, the f/3.5 AI-S one does seem quite available. In addition, the newer 24mm f/2.8 AI-S that focuses to 20cm is also decent, as is the current AF version. The 24mm f/2 is better, but pretty rare. The 28mm f/2.8 AI-S is good, better than the simpler AF version. The amazing is that all these take 52mm filters, and most of them weigh between 200g and 300g.

These guys were mostly designed in the 70’s. There’s a general theme of soft wide open and sharpening up quickly as aperture closes. They are not much better (if not worse) than modern classics as the AF-S 17-35mm f/2.8D, but are lighter, smaller and much, much cheaper.

I’ll be looking out for one of these guys, along with the 100mm f/2.8 (I think I know where I’ll find one of those). If I do decided to go for the lightweight hiking kit idea, I’ll add a few filters (I’m thinking a polarizer, a 3 stop ND and some sort of an orange filter for the clouds).

The one thing that also popped up on the hike was that without high ISO film, I’ll need a tripod for a lot of shots. So… about those carbon fibre Manfrottos…