This a question that I have wondered about for a number of years. It is not a Leica question but deals with the philosophy of lens design and marketing.

According to their literature, Nikon makes 16 mm, 18 mm and 20 mm lenses in the AF mount. Is there some practical reason for doing that? I use AI lenses in those focal lengths and can't think of one.

Maybe you can.

Art

-- Art (AKarr90975@aol.com), May 04, 2001

Answers

1) Marketing. 2) Production consistency = lower production costs. 3) The D function - e.g. for flash and matrix metering control - requires that the body know what distance the lens is set to. Does this really require "auto-focus" or just focus feedback? The latter, but then you're back to one-off production costs again.

-- Ken Shipman (kennyshipman@aol.com), May 04, 2001.

Nikon does not currently offer any AIS superwides that work with the Matrix metering systems in any of the current AF cameras. Also, the newest series of consumer AF cameras from Nikon (Like the N80, N65) will not METER AT ALL with any of the AI lenses, so those users would have to have the AF wides otherwise they'd have no in camera meter.

-- Andrew Schank (aschank@flash.net), May 04, 2001.

Ken:

1) Marketing. 2) Production consistency = lower production costs.

I would guess that those make sense. Since, I mostly use an F2 with a non-metering prism, I hadn't considered the matrix metering connection. I wouldn't have the courage to try a flash set-up with a 16 mm lens on a regular basis.

The question still remains: Is this a good way to design a lens? It is certainly different than the way Leica has done it. [Let me add that I am not a real fan of the Nikon lenses in AF mount. That is just a personal impression].

Thanks,,,

Art

-- Z1X4Y7 (Z1X4Y7@aol.com), May 04, 2001.

I imagine Nikon has struggled with its design philosophy ever since the Maxxum and EOS started eating substantially into Nikon's market share. But I have no idea what's really going on in their closed-door meetings, and I'm certainly in no position to discuss this with Nikon engineers, let alone give them advice. I can only speak as a consumer.

I started creeping away from Nikon and towards Leica when the F3 came out. My creeping turned into a sprint when the N-series bodies and plastic disposable lenses started appearing.

Nikon has persisted with its ancient F mount as a marketing strategy, at the expense of making great strides in lens design, all because they were afraid to enlarge the mount. Ironically here we are now with Nikon lenses being marketed without an aperature ring at all!

It doesn't make sense to me. It's inconsistent, and it smells like an in-house fight between elements of the Nikon company. Or maybe it's a sign of the times - state of the art engineering versus the pervasive global economy.

Leica may be slow, ponderous, stubborn, and behind the curve, but at least I can predict (for now anyway) their product design and its compatibility with the rest of my Leica equipment. It's also top- notch equipment. For me, right now, *THAT* is good lens design.

-- Ken Shipman (kennyshipman@aol.com), May 04, 2001.

Ken:

Well at least you understand why I like my old M3. We have been together forever.

Art

-- Art (AKarr90975@aol.com), May 04, 2001.

I would think in diferent designs for diferent quality of image, not just focal distance, and I belive those got to be diferent, I should know them, but I havenīt try, well of course marqueting, after a wile those become editorīs needs,

-- watson (al1231234@hotmail.com), May 04, 2001.

The exploitation of the enormous DOF of ultrawide lenses is not the panacea. If you shoot ultrawides in the extreme close-up range or at wider apertures, focusing can be more critical than you would imagine. Manually-focusing them critically at mid-to-longer distances is challenging on an SLR screen, especially without a split- image rangefinder aid. AF can be a nice option. I have a Tamron SP 17/3.5 I use with an Adaptall on both Leica R8 and Nikon F5, and the latter's electronic focus confirmation (otherwise an unused annoyance) is a welcome feature.

-- Jay (infininitydt@aol.com), May 05, 2001.

Jay's right. Autofocusing with an ultrwide is less distracting, not having to strain to check the split-image or ground-glass image. Easier to keep your mind on the image, as long as you are careful with what you autofocus on and use the focus-lock feature habitually.

-- Ken Shipman (kennyshipman@aol.com), May 06, 2001.

Ken

Is that not the advantage of AF in general? I don't see quite why it is so vital for WA lenses, bearing in mind the large DOFs.

-- Robin Smith (smith_robin@hotmail.com), May 08, 2001.

Jay's point is that the assumed large DOF of ultra-wide angle lenses can lull you into over-reliance on DOF alone. If that happens, a person can get some unpleasant results. Manual focusing such a lens on an SLR, however, is no picnic - error-prone and distracting at best. So the bottom line is that while autofocusing seems, on a gut level, to be particularly suited for longer lenses, in practice it's helpful for ultra wides, too.

-- Ken Shipman (kennyshipman@aol.com), May 13, 2001.