AF versus AF-S

[John Brewton]

Are there any real differences between these two type lens? Why would I want one over the other?
I shoot landscapes and occasional surfing.
Thanks for all replies.

 

[Pete Teoh]

AF lenses rely on the motor on your camera body to focus. AFS lenses have built-in motors and will usually focus more quickly than AF lenses.

For landscape shots, it's not likely to make a difference since mountains/valleys/trees don't move very quickly. For surfing, you'll probably have better success with AFS lenses.

--
Pete Teoh
http://teoh.us

 

[John Brewton]

Thanks. I figured there was a simple explanation and you provided it! Looking for an AF-S now.

 

[Anthony Cheh]

To Pete's explanation, I would only add that AF-S is usually quieter than AF, because the ultrasonic motor in the lens usually makes less noise than the coreless motor in the camera body.

Regards,

Tony

 

[John Brewton]

Is there a significant weight or length difference between them?

 

[Pete Teoh]

Since AFS lenses have motors in them, they tend to be slightly bigger and heavier.

--
Pete Teoh
http://teoh.us

 

[konstantinos_d]

So apart from the silent wave motors Nikon hasn't produced other lenses with other type of motors integrated (canon for instance has three of four integrated motor types) ?

--
Canon 350D
Canon EF 50mm f/2.5 Macro
Canon EF 100-300 f/5.6 L
Canon EF-S 18-55mm

http://www.flickr.com/photos/konstantinos_delta/

 

[Pradipta Dutta]

It is not that only AF-S lenses have an AF motor in the lens. The AF lenses also have one. The difference is that the AF-S lenses have ultra sound wave driven motor that is fast and silent while the AF lenses have screw driven motor that is slow and noisy.

--
Speed is significant and interesting but accuracy is downright fascinating
http://www.pbase.com/pradipta

 

[Pradipta Dutta]

konstantinos_d wrote:
So apart from the silent wave motors Nikon hasn't produced other
lenses with other type of motors integrated (canon for instance has
three of four integrated motor types) ?

Was that a question or a statement? If it was a statement, then it is wrong. If it was a question, then the answer is that Nikon has had multiple integrated AF motors in its lenses since AF lenses were introduced in 1983 to work on F3AF cameras.

--
Speed is significant and interesting but accuracy is downright fascinating
http://www.pbase.com/pradipta

 

[Robert Morgan]

Not quite. AF lenses do NOT have a motor in the lens. They rely on a focussing motor in the camera body, which then drives the lens. AF-S don't use the motor in the camera body.

Professional bodies have very strong focussing motors in the body and can just about match the speed of AF-S, depending on the lens. Consumer bodies have less strong motors and take more time focussing.

 

[AFS]

Nikon's various drive systems:

0) F3AF lenses- used in lens motor to focus. I don't know much about these and there were only two.

1) Screwdriver AF- uses the in-body motor to turn the lens gearing for focusing. Used in most primes and earlier zooms

2) AF-I: Internal Coreless DC Motor- I believe this is more like what Canon etc. use- a motor in the lens, not silent, using all electronic interface. However the AF-I lenses (only used in super telephotos in teh early-mid 90s) had Autofocus with manual override similar to the AF-S Ring type lenses, but with a slightly different interface (you had to keep the shutter half pressed when in m/a mode whether you were doing AF or MF)

3) AF-S Ring type (all but 2 AF-S lenses): Silent Wave Motor; similar to Canon USM. This type is a ring-type offering full time manual override with any lens it is in. Fast and silent focusing. Used in everything from $300 consumerish zooms (18-70, 24-85 3.5-4.5G) to $7000 telephotos (400/2.8D AF-S II) There are only two non-ring AF-S lenses to date....

4) AF-S Rod Type (only 2 lenses): Silent wave motor using a rod instead of ring type design- not as fast, but extremely compact. Used in lenses where full time manual override isn't important. To date, only used in AF-S DX 18-55mm f/3.5-5.6G ED and AF-S DX 55-200mm f/4.0-5.6G ED. Manual focus on these lens is only accomplished with a little ridged part of the front lens barrel (not even a true focusing ring) so it isn't a priority. If necessary, the switch on the lens is easily tripped, usually with your thumb, to provide manual focus...not like anyone would need that on these....
--
Rodenstockography made Easy- The D200 and Rodenstock 42mm f/0.75
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[Mark53]

It is not that only AF-S lenses have an AF motor in the lens.

This is simply not true. "Regular" AF lenses DO NOT have motors in them.

Why do people insist on spreading mis-information? It's my biggest pet peeve on forums such as this. If one is not 100% (OK, at least 99.99%) sure of something, then please don't make assumptions. I'm not perfect either, but if I really don't know something first-hand, I really do try and refrain from stating things I don't know.

 

[konstantinos_d]

It was ment to be a question. Thanks for the answer.

--
Canon 350D
Canon EF 50mm f/2.5 Macro
Canon EF 100-300 f/5.6 L
Canon EF-S 18-55mm

http://www.flickr.com/photos/konstantinos_delta/

 

[Pradipta Dutta]

Robert Morgan wrote:
Not quite. AF lenses do NOT have a motor in the lens. They rely on
a focussing motor in the camera body, which then drives the lens.
AF-S don't use the motor in the camera body.

Professional bodies have very strong focussing motors in the body
and can just about match the speed of AF-S, depending on the lens.
Consumer bodies have less strong motors and take more time
focussing.

We are getting into a little knit picking here. By definition, motor is a device that provides rotary movement. As we know, the screw driven AF lenses do provide rotary movement to the elements/groups inside of the barrel though the power is indeed derived from the camera body. And, btw, even the AF-S lenses derive power from the camera bodies.

--
Speed is significant and interesting but accuracy is downright fascinating
http://www.pbase.com/pradipta

 

[Pradipta Dutta]

Mark53 wrote:
This is simply not true. "Regular" AF lenses DO NOT have motors in
them.

Look at the post here -

http://forums.dpreview.com/forums/read.asp?forum=1030&message=16520426

Why do people insist on spreading mis-information? It's my biggest
pet peeve on forums such as this. If one is not 100% (OK, at least
99.99%) sure of something, then please don't make assumptions. I'm
not perfect either, but if I really don't know something
first-hand, I really do try and refrain from stating things I don't
know.

I think the same should be said here about your post.

--
Speed is significant and interesting but accuracy is downright fascinating
http://www.pbase.com/pradipta

 

[Anthony Cheh]

There is a difference between the motor, which generates the torque, and the drive system, which transmits it (and alters some characteristics, such as rpm).

Regards,

Tony

 

[Anthony Cheh]

AFS's listing looks correct. The AF-D lenses aren't separately listed because they don't actually have a different type of motor; Nikon added distance "measuring" information to the lens).

The F3AF lenses consisted of a 80 2.8 and a 200 3.5 ED IF, and only autofocused on the F3AF and F4. As far as I know, no other cameras have the software required to use the autofocus on these rather primitive (by today's standards) autofocusing systems.

Regards,

Tony

 

[Mark53]

Robert Morgan wrote:
Not quite. AF lenses do NOT have a motor in the lens. They rely on
a focussing motor in the camera body, which then drives the lens.
AF-S don't use the motor in the camera body.

Professional bodies have very strong focussing motors in the body
and can just about match the speed of AF-S, depending on the lens.
Consumer bodies have less strong motors and take more time
focussing.

We are getting into a little knit picking here. By definition,
motor is a device that provides rotary movement. As we know, the
screw driven AF lenses do provide rotary movement to the
elements/groups inside of the barrel though the power is indeed
derived from the camera body.

Sorry, this is BS. Why don't you just let it go -- you made a mistake. Nobody considers every turning device "a motor".

And, btw, even the AF-S lenses derive power from the camera bodies.

Well, obviously. Lenses are not yet nuclear powered with a self-contained urananium source. Again, give it a break.

 

[flat five]

AF-S lenses also allow you to manually focus or fine tune the focus of the lens without switching the lens or body to dedicated manual focus...

likewise, when you have your body set up to activate the AF system only by using the AF-ON button (or AE-L/AF-L button on a d70) your AF-S lenses are able to be focused manually without switching modes... if you want to focus manually, just grab the ring and go.. if you want AF, push the AF-ON button...
jeff

--
http://jeff.emptyfortunecookie.com/folio

 

[Robert Morgan]

Still wrong. AF-S lens get power from the body to drive their own motor. AF lens DO NOT have motors but have a gear that engages the motor in the body. They don't get power from the body to drive any motors at all - there are none. AF lenses do use some power from the body however to drive the cpu in the lens (which just communicates aperture and distance (for AF-D)).