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Selecting Lenses for Your New Digital SLR

This article is a follow-up to a piece I did a few months back answering some common questions posed by photographers upgrading from a consumer camera to a DSLR. Since that article, I have received many questions from people wondering which lenses would be good to purchase for their first dives with their new Digital Rebel. There has also been an exciting new camera called the D70 released by Nikon at $1,299 including a very good lens.

I will present what I consider to be a good “stable” of beginner lenses and explain why I recommend them. These lenses were selected with an entry-level perspective in mind, so none of them exceed $350 in cost. Then I'll talk about using these lenses underwater, inside an underwater housing and behind a port.

Since I have most of my experience using Nikon systems, the underwater photos in this article won't include any shots taken with Canon lenses. Don't worry though, Canon and Sigma provide a stable of almost exactly the same glass at a very similar price point.

A good beginner “stable” of lenses for a digital SLR. Kit lens, 60mm macro, and full frame fisheye.

I think that everyone buying the Digital Rebel or the D70 should purchase it with the kit lens. These lenses have focal lengths of 18-55mm and 18-70mm respectively. They both provide a relatively wide field of view but also have good close focusing ability. Most housing manufacturers will recommend using this type of lens behind a dome port. Depending on which dome is use, these lenses might need a screw on diopter (sometimes called a “closeup lens”) to focus properly. The following photo shows the Nikon 18-35mm lens in the Aquatica housing – if a diopter is needed, it can be screwed onto the front filter thread. I don't have the 18-70mm lens yet, so I have substituted the 18-35mm for this article. I recommend this type of lens because it is inexpensive, comes bundled with the kit, and can shoot subjects from about 8” in size up to “scuba diver size.”

The Aquatica housing with a zoom lens mounted. The 60mm is at right for scale.

I have selected some shots which I think are representative of what the 18-70 can do, but taken with my 18-35mm behind the Ikelite extended dome port. These shots required a +4 diopter mounted to the lens. I hope to try the 18-70mm DX lens soon, but at the time of this writing (March 2004), it is not yet in stock at dealers.

The 18-35mm at the “long end.” This end of the zoom can be used for fish portraits, behavior shots, etc.

The 18-35mm at the wide end .

The next lens I will focus on (no pun intended) is the 60mm macro made by Nikon. This lens can focus down to a 1:1 reproduction ratio (35mm equivalent). Canon makes a similar lens, the 50mm f2.5, but the Canon lens only provides half the magnification. Shooting 1:1 macro is certainly rewarding, and this is a consideration for Canon shooters, but most beginners will probably stick to slightly larger subjects. Users have reported that the Sigma 50mm lens for either Canon or Nikon mount can do 1:1 (35mm equivalent) but that the autofocus is not as fast as the more expensive “name brand” lenses. In any case, this isn't as relevant for beginning DSLR shooters, because most subjects will range in size from about 3” up to roughly 18” so 2:1 (35mm equivalent) should be fine. All of these macro lenses can be used behind a small flat port and they do not require manual focusing to get good sharp shots.

60mm shot of an amberjack eye – taken about 10” from the subject.

Another shot with the 60mm, taken about one foot from the subject

The 60mm at far focus – I was able to capture the whole fish at about 3 feet from the subject.

The last of the three lenses to get is a full frame fisheye. I recommend the Sigma 15mm f2.8, which comes in either a Nikon or Canon mount. This lens is a very good performer and does the job of a Nikkor 16mm fisheye at about half the price. The 15mm is not a 180 degree fisheye on a DSLR, because it is cropped, but will still cover somewhere near a 100 degree field of view. Straight vertical or horizontal lines at the top, bottom, or sides of the frame will be curved, but this is seldom a problem underwater; in fact, it is almost impossible to tell that most shots taken with this lens were made with a fisheye. The 15mm focuses extremely close and can be used behind most dome ports. An added bonus of shooting the 15mm is that this lens will force you to get close to your subjects. A variety of marine critters make good subjects, but as a rule - even at close focus - the subject should be bigger than about two feet, or it will be dwarfed by this lens. Of course the reason for shooting a lens with this wide field of view is that you can get a BIG subject in the frame, and at 3 to 5 feet away, you can light it well to bring out color.

A shot of a hawksbill turtle taken with the Nikon 16mm Fisheye – the subject was less than three feet from the lens.

Wetpixel Administrator Craig Jones shooting a rope sponge with his Nexus D100 and Inon strobes. The coral in the foreground is over ten feet across. Nikkor 16mm

I hope that this short article has provided a good guide for beginning DSLR shooters. All of the lenses discussed in this article can be obtained new for about $300 (18-70DX) to $350 (15mm and 60mm). If you have further questions, I'd encourage you to visit the Underwater Digital SLR discussion forum at Wetpixel.